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  • 201. Ahrens, J.
    et al.
    Bai, X.
    Barouch, G.
    Barwick, S. W.
    Bay, R. C.
    Becka, T.
    Becker, K. -H
    Bertrand, D.
    Binon, F.
    Biron, A.
    Böser, S.
    Booth, J.
    Botner, O.
    Bouchta, A.
    Bouhali, O.
    Boyce, M. M.
    Burgess, T.
    Carius, Staffan
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Chen, A.
    Chirkin, D.
    Conrad, J.
    Cooley, J.
    Costa, C. G. S.
    Cowen, D. F.
    Davour, A.
    De Clercq, C.
    DeYoung, T.
    Desiati, P.
    Dewulf, J. -P
    Doksus, P.
    Ekström, P.
    Feser, T.
    Frère, J. -M
    Gaisser, T. K.
    Gaug, M.
    Geenen, H.
    Goldschmidt, A.
    Hallgren, A.
    Halzen, F.
    Hanson, K.
    Hardtke, R.
    Hauschildt, T.
    Hellwig, M.
    Hill, G. C.
    Hulth, P. O.
    Hultqvist, K.
    Hundertmark, S.
    Jacobsen, J.
    Karle, A.
    Kim, J.
    Koci, B.
    Köpke, L.
    Kowalski, M.
    Lamoureux, J. I.
    Leich, H.
    Leuthold, M.
    Lindahl, P.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Liubarsky, I.
    Lowder, D. M.
    Madsen, J.
    Marciniewski, P.
    Matis, H. S.
    McParland, C. P.
    Messarius, T.
    Miller, T. C.
    Minaeva, Y.
    Miočinović, P.
    Mock, P. C.
    Morse, R.
    Neunhöffer, T.
    Niessen, P.
    Nygren, D. R.
    Ogelman, H.
    Olbrechts, Ph.
    De Los Heros, C. P.
    Pohl, A. C.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Porrata, R.
    Price, P. B.
    Przybylski, G. T.
    Rawlins, K.
    Reed, C.
    Resconi, E.
    Rhode, W.
    Ribordy, M.
    Richter, S.
    Martino, J. R.
    Romenesko, P.
    Ross, D.
    Sander, H. -G
    Schinarakis, K.
    Schmidt, T.
    Schneider, D.
    Schwarz, R.
    Silvestri, A.
    Solarz, M.
    Spiczak, G. M.
    Spiering, C.
    Starinsky, N.
    Steele, D.
    Search for neutrino-induced cascades with the AMANDA detector2003In: Physical Review D, ISSN 1550-7998, E-ISSN 1550-2368, Vol. 67, no 1, p. 012003-Article in journal (Refereed)
    Abstract [en]

    We report on a search for electromagnetic and/or hadronic showers (cascades) induced by a diffuse flux of neutrinos with energies between 5 TeV and 300 TeV from extraterrestrial sources. Cascades may be produced by matter interactions of all flavors of neutrinos, and contained cascades have better energy resolution and afford better background rejection than throughgoing νμ-induced muons. Data taken in 1997 with the AMANDA detector were searched for events with a high-energy cascadelike signature. The observed events are consistent with expected backgrounds from atmospheric neutrinos and catastrophic energy losses from atmospheric muons. Effective volumes for all flavors of neutrinos, which allow the calculation of limits for any neutrino flux model, are presented. The limit on cascades from a diffuse flux of νe+ νμ + ντ+ ν̄e + ν̄μ+ ν̄τ is E2(dΦ/dE)<9.8×10-6 GeV cm-2 s-1 sr-1, assuming a neutrino flavor flux ratio of 1:1:1 at the detector. The limit on cascades from a diffuse flux of νe+ν̄e is E2(dΦ/dE)<6. 5×10-6 GeV cm-2 s-1 sr-1, independent of the assumed neutrino flavor flux ratio. © 2003 The American Physical Society.

  • 202. Ahrens, J.
    et al.
    Bai, X.
    Barouch, G.
    Barwick, S. W.
    Bay, R. C.
    Becka, T.
    Becker, K. H.
    Bertrand, D.
    Biron, A.
    Booth, J.
    Botner, O.
    Bouchta, A.
    Boyce, M. M.
    Carius, Staffan
    University of Kalmar, Department of Technology.
    Chen, A.
    Chirkin, D.
    Conrad, J.
    Cooley, J.
    Costa, C. G. S.
    Cowen, D. F.
    Dalberg, E.
    DeYoung, T.
    Desiati, P.
    Dewulf, J. P.
    Doksus, P.
    Edsjo, J.
    Ekstrom, P.
    Feser, T.
    Gaug, M.
    Goldschmidt, A.
    Hallgren, A.
    Halzen, F.
    Hanson, K.
    Hardtke, R.
    Hellwig, M.
    Hill, G. C.
    Hulth, P. O.
    Hundertmark, S.
    Jacobsen, J.
    Karle, A.
    Kim, J.
    Koci, B.
    Kopke, M.
    Kowalski, M.
    Lamoureux, J. I.
    Leich, H.
    Leuthold, P.
    Lindahl, P.
    University of Kalmar, Department of Technology.
    Loaiza, P.
    Ludvig, J.
    Madsen, J.
    Marciniewski, P.
    Matis, H. S.
    Miller, T. C.
    Minaeva, Y.
    Miocinovic, P.
    Morse, R.
    Neuhoffer, T.
    Niessen, P.
    Nygren, D. R.
    Ogelman, H.
    Perez de los Heros, C.
    Pohl, A.
    University of Kalmar, Department of Technology.
    Price, P. B.
    Rawlins, K.
    Reed, C.
    Rhode, W.
    Richter, S.
    Rodriguez Martino, J.
    Romenesko, P.
    Ross, D.
    Sander, H. G.
    Schmidt, T.
    Schneider, D.
    Schwarz, R.
    Silvestri, A.
    Solarz, M.
    Spiczak, G.
    Spiering, C.
    Starinski, N.
    Steele, D.
    Steffen, P.
    Stokstad, R. G.
    Streicher, O.
    Sudhoff, P.
    Taboada, I.
    Thollander, L.
    Vander Donckt, M.
    Walck, C.
    Weinheimer, C.
    Wiebusch, C. H.
    Wischnewski, R.
    Wissing, H.
    Woschnagg, K.
    Wu, W.
    Yodh, G.
    Young, S.
    Initial results from AMANDA2001In: 21st Rencontres de Moriond Workshop on Very High-Energy Phenomena in the Universe, 2001Conference paper (Refereed)
  • 203. Ahrens, J.
    et al.
    Bai, X.
    Barouch, G.
    Barwick, S. W.
    Bay, R. C.
    Becka, T.
    Becker, K. -H
    Bertrand, D.
    Biron, A.
    Booth, J.
    Botner, O.
    Bouchta, A.
    Boyce, M. M.
    Carius, Staffan
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Chen, A.
    Chirkin, D.
    Conrad, J.
    Cooley, J.
    Costa, C. G. S.
    Cowen, D. F.
    Dalberg, E.
    DeYoung, T.
    Desiati, P.
    Dewulf, J. -P
    Doksus, P.
    Edsjö, J.
    Ekström, P.
    Feser, T.
    Gaug, M.
    Goldschmidt, A.
    Hallgren, A.
    Halzen, F.
    Hanson, K.
    Hardtke, R.
    Hellwig, M.
    Heukenkamp, H.
    Hill, G. C.
    Hulth, P. O.
    Hundertmark, S.
    Jacobsen, J.
    Karle, A.
    Kim, J.
    Koci, B.
    Köpke, L.
    Kowalski, M.
    Lamoureux, J. I.
    Leich, H.
    Leuthold, M.
    Lindahl, P.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Liubarsky, I.
    Loaiza, P.
    Lowder, D. M.
    Madsen, J.
    Marciniewski, P.
    Matis, H. S.
    Miller, T. C.
    Minaeva, Y.
    Miočinović, P.
    Mock, P. C.
    Morse, R.
    Neunhöffer, T.
    Niessen, P.
    Nygren, D. R.
    Ogelman, H.
    Pérez de los Heros, C.
    Porrata, R.
    Price, P. B.
    Rawlins, K.
    Reed, C.
    Rhode, W.
    Richter, S.
    Rodríguez Martino, J.
    Romenesko, P.
    Ross, D.
    Sander, H. -G
    Schmidt, T.
    Schneider, D.
    Schwarz, R.
    Silvestri, A.
    Solarz, M.
    Spiczak, G. M.
    Spiering, C.
    Starinsky, N.
    Steele, D.
    Steffen, P.
    Stokstad, R. G.
    Streicher, O.
    Sudhoff, P.
    Taboada, I.
    Thollander, L.
    Thon, T.
    Tilav, S.
    Vander Donckt, M.
    Walck, C.
    Weinheimer, C.
    Wiebusch, C. H.
    Wischnewski, R.
    Wissing, H.
    Woschnagg, K.
    Wu, W.
    Yodh, G.
    Young, S.
    Search for supernova neutrino bursts with the AMANDA detector2001In: Astroparticle physics, ISSN 0927-6505, E-ISSN 1873-2852, Vol. 16, no 4, p. 345-359Article in journal (Refereed)
    Abstract [en]

    The core collapse of a massive star in the Milky Way will produce a neutrino burst, intense enough to be detected by existing underground detectors. The AMANDA neutrino telescope located deep in the South Pole ice can detect MeV neutrinos by a collective rate increase in all photo-multipliers on top of dark noise. The main source of light comes from positrons produced in the CC reaction of anti-electron neutrinos on free protons ve + p → e+ + n. This paper describes the first supernova search performed on the full sets of data taken during 1997 and 1998 (215 days of live time) with 302 of the detector's optical modules. No candidate events resulted from this search. The performance of the detector is calculated, yielding a 70% coverage of the galaxy with one background fake per year with 90% efficiency for the detector configuration under study. An upper limit at the 90% c.l. on the rate of stellar collapses in the Milky Way is derived, yielding 4.3 events per year. A trigger algorithm is presented and its performance estimated. Possible improvements of the detector hardware are reviewed.

  • 204. Ahrens, J.
    et al.
    Bai, X.
    Barouch, G.
    Barwick, S. W.
    Bay, R. C.
    Becka, T.
    Becker, K. H.
    Bertrand, D.
    Biron, A.
    Booth, J.
    Botner, O.
    Bouchta, A.
    Boyce, M. M.
    Carius, Staffan
    University of Kalmar, Department of Technology.
    Chen, A.
    Chirkin, D.
    Conrad, Jan
    Cooley, J.
    Costa, C. G. S.
    Cowen, D. F.
    De Clercq, C.
    DeYoung, T.
    Desiati, P.
    Dewulf, J. P.
    Doksus, P.
    Edsjo, J.
    Ekstrom, P.
    Feser, T.
    Gaisser, S.
    Gaug, M.
    Gerhardt, L.
    Goldschmidt, A.
    Hallgren, A.
    Halzen, F.
    Hanson, K.
    Hardtke, R.
    Hauschildt, T.
    Hellwig, M.
    Herquet, P.
    Hill, G. C.
    Hulth, P. O.
    Hundertmark, S.
    Jacobsen, J.
    Karle, A.
    Kim, J.
    Koci, B.
    Kopke, L.
    Kowalski, M.
    Lamoureux, J. I.
    Leich, H.
    Leuthold, M.
    Lindahl, P.
    University of Kalmar, Department of Technology.
    Madsen, J.
    Marciniewski, P.
    Matis, H. S.
    Minaeva, Y.
    Miocinovic, P.
    Morse, R.
    Neunhoffer, T.
    Niessen, P.
    Nygren, D. R.
    Ogelman, H.
    Olbrechts, P.
    Peres de los Heros, C.
    Price, P. B.
    Rawlins, K.
    Reed, C.
    Ribordy, M.
    Rhode, W.
    Richter, S.
    Rodriguez Martino, J.
    Ross, D.
    Sander, H. G.
    Schmidt, T.
    Schneider, D.
    Silvestri, A.
    Solarz, M.
    Spiczak, G. M.
    Spiering, C.
    Starinsky, N.
    Steele, D.
    Steffen, P.
    Stokstad, R. G.
    Sudhoff, P.
    Sulanke, K. H.
    Taboada, I.
    Vander Donckt, M.
    Walck, C.
    Weinheimer, C.
    Wiebusch, C. H.
    Wischnewski, R.
    Wissing, H.
    Woschnagg, K.
    Yodh, G.
    Young, S.
    Results from AMANDA2001In: Proceedings, 9th International Workshop, Venice, Italy, March 6-9, 2001. Vol. 1, 2: Neutrino telescopes / [ed] M. Baldo-Ceolin, 2001, p. 569-580Conference paper (Refereed)
  • 205. Ahrens, J.
    et al.
    Bai, X.
    Barwick, S. W.
    Bay, R. C.
    Becka, T.
    Becker, K. -H
    Bernardini, E.
    Bertrand, D.
    Binon, F.
    Biron, A.
    Böser, S.
    Botner, O.
    Bouchta, A.
    Bouhali, O.
    Burgess, T.
    Carius, Staffan
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Castermans, T.
    Chirkin, D.
    Conrad, J.
    Cooley, J.
    Cowen, D. F.
    Davour, A.
    de Clercq, C.
    DeYoung, T.
    Desiati, P.
    Doksus, P.
    Ekström, P.
    Engel, R.
    Evenson, P.
    Feser, T.
    Gaisser, T. K.
    Ganugapati, R.
    Gaug, M.
    Geenen, H.
    Gerhardt, L.
    Goldschmidt, A.
    Hallgren, A.
    Halzen, F.
    Hanson, K.
    Hardtke, R.
    Hauschildt, T.
    Hellwig, M.
    Herquet, P.
    Hill, G. C.
    Hinton, J. A.
    Hughey, B.
    Hulth, P. O.
    Hultqvist, K.
    Hundertmark, S.
    Jacobsen, J.
    Karle, A.
    Kim, J.
    Köpke, L.
    Kowalski, M.
    Kuehn, K.
    Lamoureux, J. I.
    Leich, H.
    Leuthold, M.
    Lindahl, P.
    Liubarsky, I.
    Lloyd-Evans, J.
    Madsen, J.
    Mandli, K.
    Marciniewski, P.
    Martello, D.
    Matis, H. S.
    McParland, C. P.
    Messarius, T.
    Miller, T. C.
    Minaeva, Y.
    Miočinović, P.
    Mock, P. C.
    Morse, R.
    Neunhöffer, T.
    Niessen, P.
    Nygren, D. R.
    Ögelman, H.
    Olbrechts, P.
    Perez de los Heros, C.
    Pohl, A. C.
    Porrata, R.
    Price, P. B.
    Przybylski, G. T.
    Rawlins, K.
    Resconi, E.
    Rhode, W.
    Ribordy, M.
    Richter, S.
    Rochester, K.
    Rodríguez Martino, J.
    Romenesko, P.
    Ross, D.
    Sander, H. -G
    Schmidt, T.
    Schinarakis, K.
    Schlenstedt, S.
    Schneider, D.
    Schwarz, R.
    Silvestri, A.
    Solarz, M.
    Splczak, G. M.
    Spiering, C.
    Stamatikos, M.
    Stanev, T.
    Steele, D.
    Steffen, P.
    Stokstad, R. G.
    Sulanke, K. -H
    Taboada, I.
    Tilav, S.
    Walck, C.
    Wagner, W.
    Wang, Y. -R
    Watson, A. A.
    Weinheimer, C.
    Wiebusch, C. H.
    Wiedemann, C.
    Wischnewski, R.
    Wissing, H.
    Woschnagg, K.
    Wu, W.
    Yodh, G.
    Young, S.
    Calibration and survey of AMANDA with the SPASE detectors2004In: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, ISSN 0168-9002, E-ISSN 1872-9576, Vol. 522, no 3, p. 347-359Article in journal (Refereed)
    Abstract [en]

    We report on the analysis of air showers observed in coincidence by the Antarctic Muon and Neutrino detector array (AMANDA-B10) and the South Pole Air Shower Experiment (SPASE-1 and SPASE-2). We discuss the use of coincident events for calibration and survey of the deep AMANDA detector as well as the response of AMANDA to muon bundles. This analysis uses data taken during 1997 when both SPASE-1 and SPASE-2 were in operation to provide a stereo view of AMANDA. © 2003 Elsevier B.V. All rights reserved.

  • 206. Ahrens, J.
    et al.
    Bai, X.
    Barwick, S. W.
    Bay, R. C.
    Becka, T.
    Becker, K. -H
    Bernardini, E.
    Bertrand, D.
    Biron, A.
    Boeser, S.
    Botner, O.
    Bouchta, A.
    Bouhali, O.
    Burgess, T.
    Carius, Staffan
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Castermans, T.
    Chirkin, D.
    Conrad, J.
    Cooley, J.
    Cowen, D. F.
    Davour, A.
    de Clercq, C.
    DeYoung, T.
    Desiati, P.
    Doksus, P.
    Ekström, P.
    Feser, T.
    Gaisser, T. K.
    Ganugapati, R.
    Gaug, M.
    Geenen, H.
    Gerhardt, L.
    Goldschmidt, A.
    Hallgren, A.
    Halzen, F.
    Hanson, K.
    Hardtke, R.
    Hauschildt, T.
    Hellwig, M.
    Herquet, P.
    Hill, G. C.
    Hulth, P. O.
    Hughey, B.
    Hultqvist, K.
    Hundertmark, S.
    Jacobsen, J.
    Karle, A.
    Kuehn, K.
    Kim, J.
    Köpke, L.
    Kowalski, M.
    Lamoureux, J. I.
    Leich, H.
    Leuthold, M.
    Lindahl, P.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Liubarsky, I.
    Madsen, J.
    Mandli, K.
    Marciniewski, P.
    Matis, H.
    McParland, C. P.
    Messarius, T.
    Miller, T. C.
    Minaeva, Y.
    Miocinović, P.
    Mock, P. C.
    Morse, R.
    Neunhöffer, T.
    Niessen, P.
    Nygren, D. R.
    Ögelman, H.
    Olbrechts, P.
    Pérez de los Heros, C.
    Pohl, A. C.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Porrata, R.
    Price, P. B.
    Przybylski, G. T.
    Rawlins, K.
    Resconi, E.
    Rhode, W.
    Ribordy, M.
    Richter, S.
    Rodríguez Martino, J.
    Romenesko, P.
    Ross, D.
    Sander, H. -G
    Schlenstedt, S.
    Schinarakis, K.
    Schmidt, T.
    Schneider, D.
    Schwarz, R.
    Silvestri, A.
    Solarz, M.
    Stamatikos, M.
    Spiczak, G. M.
    Spiering, C.
    Steele, D.
    Steffen, P.
    Stokstad, R. G.
    Sulanke, K. -H
    Taboada, I.
    Tilav, S.
    Wagner, W.
    Walck, C.
    Wang, Y. -R
    Wiebusch, C. H.
    Wiedemann, C.
    Wischnewski, R.
    Wissing, H.
    Woschnagg, K.
    Wu, W.
    Yodh, G.
    Young, S.
    Limits on diffuse fluxes of high energy extraterrestrial neutrinos with the AMANDA-B10 detector2003In: Physical Review Letters, ISSN 0031-9007, E-ISSN 1079-7114, Vol. 90, no 25, p. 2511011-2511015Article in journal (Refereed)
    Abstract [en]

    A report on the limits, which could be placed on diffuse fluxes of high energy extraterrestrial neutrinos, was presented. The incorporation of neutrino oscillations was necessary for interpreting the limits in terms of the flux from a cosmological distributions of sources. The energetic accelerated environments were presented as the sources of high energy extraterrestrial neutrinos.

  • 207. Ahrens, J.
    et al.
    Bai, X.
    Barwick, S. W.
    Becka, T.
    Becker, J. K.
    Bernardini, E.
    Bertrand, D.
    Binon, F.
    Biron, A.
    Boersma, D. J.
    Böser, S.
    Botner, O.
    Bouchta, A.
    Bouhali, O.
    Burgess, T.
    Carius, Staffan
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Castermans, T.
    Chen, A.
    Chirkin, D.
    Collin, B.
    Conrad, J.
    Cooley, J.
    Cowen, D. F.
    Davour, A.
    de Clercq, C.
    DeYoung, T.
    Desiati, P.
    Dewulf, J. P.
    Ekström, P.
    Feser, T.
    Gaisser, T. K.
    Ganugapati, R.
    Gaug, M.
    Geenen, H.
    Gerhardt, L.
    Goldschmidt, A.
    Groß, A.
    Hallgren, A.
    Halzen, F.
    Hanson, K.
    Hardtke, R.
    Harenberg, T.
    Hauschildt, T.
    Helbing, K.
    Hellwig, M.
    Herquet, P.
    Hill, G. C.
    Hubert, D.
    Hughey, B.
    Hulth, P. O.
    Hultqvist, K.
    Hundertmark, S.
    Jacobsen, J.
    Karle, A.
    Kestel, M.
    Köpke, L.
    Kowalski, M.
    Kuehn, K.
    Lamoureux, J. I.
    Leich, H.
    Leuthold, M.
    Lindahl, P.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Liubarsky, I.
    Madsen, J.
    Mandli, K.
    Marciniewski, P.
    Matis, H. S.
    McParland, C. P.
    Messarius, T.
    Minaeva, Y.
    Miočinović, P.
    Morse, R.
    Münich, K.
    Nahnhauer, R.
    Neunhöffer, T.
    Niessen, P.
    Nygren, D. R.
    Ögelman, H.
    Olbrechts, P.
    Perez de los Heros, C.
    Pohl, A. C.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Porrata, R.
    Price, P. B.
    Przybylski, G. T.
    Rawlins, K.
    Resconi, E.
    Rhode, W.
    Ribordy, M.
    Richter, S.
    Rodríguez Martino, J.
    Sander, H. G.
    Schinarakis, K.
    Schlenstedt, S.
    Schmidt, T.
    Schneider, D.
    Schwarz, R.
    Silvestri, A.
    Solarz, M.
    Spiczak, G. M.
    Spiering, C.
    Stamatikos, M.
    Steele, D.
    Steffen, P.
    Stokstad, R. G.
    Sulanke, K. H.
    Taboada, I.
    Thollander, L.
    Tilav, S.
    Wagner, W.
    Walck, C.
    Wang, Y. R.
    Wiebusch, C. H.
    Wiedemann, C.
    Wischnewski, R.
    Wissing, H.
    Woschnagg, K.
    Yodh, G.
    Search for Extraterrestrial Point Sources of Neutrinos with AMANDA-II2004In: Physical Review Letters, ISSN 0031-9007, E-ISSN 1079-7114, Vol. 92, no 7, p. 711021-711025Article in journal (Refereed)
    Abstract [en]

    The results of a search for point sources of high energy neutrinos in the northern hemisphere were presented using AMANDA-II data collected in the year 2000. The results included the flux limits on several active-galactic-nuclei blazars, microquasars, magnetars, and other candidate neutrino sources. A search for excesses above a random background of cosmic ray induced atmospheric neutrinos and misreconstructed downgoing cosmic-rays muons, which revealed no statistically significant neutrino point sources was also presented. It was shown that AMANDA-II had achieved the sensitivity required to probe known TeV γ-ray sources such as the blazar Markarian 501 in its 1997 flaring state at a level where neutrino and γ-ray fluxes were equal.

  • 208. Ahrens, J.
    et al.
    Bai, X.
    Barwick, S. W.
    Becka, T.
    Becker, K. -H
    Bernardini, E.
    Bertrand, D.
    Binon, F.
    Biron, A.
    Böser, S.
    Botner, O.
    Bouhali, O.
    Burgess, T.
    Carius, Staffan
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Castermans, T.
    Chen, A.
    Chirkin, D.
    Conrad, J.
    Cooley, J.
    Cowen, D. F.
    Davour, A.
    De Clercq, C.
    De Young, T.
    Desiati, P.
    Dewulf, J. -P
    Doksus, P.
    Ekström, P.
    Feser, T.
    Gaisser, T. K.
    Gaug, M.
    Gerhardt, L.
    Godschmidt, A.
    Hallgren, A.
    Halzen, F.
    Hanson, K.
    Hardtke, R.
    Hauschildt, T.
    Hellwig, M.
    Herquet, P.
    Hill, G. C.
    Hulth, P. O.
    Hundertmark, S.
    Jacobson, J.
    Karle, A.
    Koci, B.
    Köpke, L.
    Kuehn, P.
    Kowalski, M.
    Lamoureux, J. I.
    Leich, H.
    Leuthold, M.
    Lindahl, P.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Liubarsky, I.
    Madsen, J.
    Marciniewski, P.
    Matis, H. S.
    McParland, C. P.
    Minaeva, Y.
    Miočinovć, P.
    Morse, R.
    Nahnhauer, R.
    Neunhöffer, T.
    Niessen, P.
    Nygren, D. R.
    Ogelman, H.
    Olbrechts, Ph.
    Péres de los Heros, C.
    Pohl, A. C.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Price, P. B.
    Przybylski, G. T.
    Rawlins, K.
    Resconi, E.
    Rhode, W.
    Ribordy, M.
    Richter, S.
    Rodríguez Martino, J.
    Ross, D.
    Sander, H. -G
    Schmidt, T.
    Schneider, D.
    Schwarz, R.
    Silvestri, A.
    Solarz, M.
    Spiczak, G. M.
    Spiering, C.
    Steele, D.
    Steffen, P.
    Stokstad, R. G.
    Sudhoff, P.
    Sulanke, K. -H
    Taboada, I.
    Thollander, L.
    Tilay, S.
    Walck, C.
    Weinheimer, C.
    Wiebusch, C. H.
    Wiedemann, C.
    Wissing, H.
    Results from the Antarctic muon and nuetrino detector array2003In: Nuclear physics B, Proceedings supplements, ISSN 0920-5632, E-ISSN 1873-3832, Vol. 118, p. 371-379Article in journal (Refereed)
    Abstract [en]

    We show new results from both the older and newer incarnations of AMANDA (AMANDA-B10 and AMANDA-II, respectively). These results demonstrate that AMANDA is a functioning, multipurpose detector with significant physics and astrophysics reach. They include a new higher-statistics measurement of the atmospheric muon neutrino flux and preliminary results from searches for a variety of sources of ultrahigh energy neutrinos: generic point sources, gamma-ray bursters and diffuse sources producing muons in the detector, and diffuse sources producing electromagnetic or hadronic showers in or near the detector.

  • 209. Ahrens, J.
    et al.
    Bai, X.
    Barwick, S. W.
    Becka, T.
    Becker, K. -H
    Bernardini, E.
    Bertrand, D.
    Binon, F.
    Biron, A.
    Böser, S.
    Botner, O.
    Bouhali, O.
    Burgess, T.
    Carius, Staffan
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Castermans, T.
    Chirkin, D.
    Conrad, J.
    Cooley, J.
    Cowen, D. F.
    Davour, A.
    de Clercq, C.
    de Young, T.
    Desiati, P.
    Dewulf, J. -P
    Ekström, P.
    Feser, T.
    Gaisser, T. K.
    Ganupati, R.
    Gaug, M.
    Geenen, H.
    Gerhardt, L.
    Goldschmidt, A.
    Hallgren, A.
    Halzen, F.
    Hanson, K.
    Hardtke, R.
    Hauschildt, T.
    Hellwig, M.
    Herquet, P.
    Hill, G. C.
    Hulth, P. O.
    Hultqvist, K.
    Hundertmark, S.
    Jacobsen, J.
    Karle, A.
    Köpke, L.
    Kuehn, K.
    Kowalski, M.
    Lamoureux, J. I.
    Leich, H.
    Leuthold, M.
    Lindahl, P.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Liubaxsky, I.
    Madsen, J.
    Mandli, K.
    Marciniewski, P.
    Matis, H. S.
    McParland, C. P.
    Messarius, T.
    Minaeva, Y.
    Miočinović, P.
    Morse, R.
    Nahnhauer, R.
    Neunhöffer, T.
    Niessen, P.
    Nygren, D. R.
    Ogelman, H.
    Olbrechts, P.
    Pérez de los Heros, C.
    Pohl, A. C.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Price, P. B.
    Przybylski, G. T.
    Rawlins, K.
    Resconi, E.
    Rhode, W.
    Ribordy, M.
    Richter, S.
    Rodríguez Martino, J.
    Sander, H. -G
    Schmidt, T.
    Schneider, D.
    Schinarakis, K.
    Schwarz, R.
    Silvestri, A.
    Solarz, M.
    Spiczak, G. M.
    Spiering, C.
    Steele, D.
    Steffen, P.
    Stokstad, R. G.
    Sudoff, P.
    Sulanke, K. -H
    Taboada, I.
    Thollander, L.
    Tilav, S.
    Wagner, W.
    Walck, C.
    Weinheimer, C.
    Wiebusch, C. H.
    Wiedemann, C.
    Wischnewski, R.
    Wissing, H.
    Woschnagg, K.
    Yodh, G.
    Young, S.
    Results from the AMANDA telescope2003In: Nuclear Physics A, ISSN 0375-9474, E-ISSN 1873-1554, Vol. 721, p. C545-C548Article in journal (Refereed)
    Abstract [en]

    We present results from the AMANDA high energy neutrino telescope located at the South Pole. They include measurements of the atmospheric neutrino flux, search for UHE point sources, and diffuse sources producing electromagnetic/hadronic showers at the detector or close to it.

  • 210. Ahrens, J.
    et al.
    Bai, X.
    Barwick, S. W.
    Becka, T.
    Becker, K. -H
    Bertrand, D.
    Binon, F.
    Biron, A.
    Böser, S.
    Botner, O.
    Bouhali, O.
    Burgess, T.
    Carius, Staffan
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Castermans, T.
    Chirkin, D.
    Conrad, J.
    Cooley, J.
    Cowen, D. F.
    Davour, A.
    de Clercq, C.
    DeYoung, T.
    Desiati, P.
    Dewulf, J. -P
    Doksus, P.
    Ekström, P.
    Feser, T.
    Gaisser, T. K.
    Gaug, M.
    Gerhardt, L.
    Goldschmidt, A.
    Hallgren, A.
    Halzen, F.
    Hanson, K.
    Hardtke, R.
    Hauschildt, T.
    Hellwig, M.
    Herquet, P.
    Hill, G. C.
    Hulth, P. O.
    Hultqvist, K.
    Hundertmark, S.
    Jacobsen, J.
    Karle, A.
    Köpke, L.
    Kowalski, M.
    Kuehn, K.
    Lamoureux, J. I.
    Leich, H.
    Leuthold, M.
    Lindahl, P.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Madsen, J.
    Marciniewski, P.
    Matis, H. S.
    McParland, C. P.
    Minaeva, Y.
    Miočinović, P.
    Morse, R.
    Nahnhauer, R.
    Neunhöffer, T.
    Niessen, P.
    Nygren, D. R.
    Ogelman, H.
    Olbrechts, P.
    Pérez de los Heros, C.
    Pohl, A. C.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Price, P. B.
    Przybylski, G. T.
    Rawlins, K.
    Resconi, E.
    Rhode, W.
    Ribordy, M.
    Richter, S.
    Rodríguez Martino, J.
    Ross, D.
    Sander, H. -G
    Schmidt, T.
    Schneider, D.
    Schwarz, R.
    Silvestri, A.
    Solarz, M.
    Spiczak, G. M.
    Spiering, C.
    Steele, D.
    Steffen, P.
    Stokstad, R. G.
    Sudhoff, P.
    Sulanke, K. -H
    Taboada, I.
    Thollander, L.
    Tilav, S.
    Walck, C.
    Weinheimer, C.
    Wiebusch, C. H.
    Wiedemann, C.
    Wischnewski, R.
    Wissing, H.
    Woschnagg, K.
    Yodh, G.
    Young, S.
    Physics and operation of the AMANDA-II high energy neutrino telescope2002In: Proceedings of the SPIE - The International Society for Optical Engineering 2003, Institution of Electrical Engineers (IEE), 2002, p. 79-91Conference paper (Refereed)
    Abstract [en]

    This paper briefly describes the principle of operation and science goals of the AMANDA high energy neutrino telescope located at the South Pole, Antarctica. Results from an earlier phase of the telescope, called AMANDA-B10, demonstrate both reliable operation and the broad astrophysical reach of this device, which includes searches for a variety of sources of ultrahigh energy neutrinos: generic point sources, Gamma-Ray Bursts and diffuse sources. The predicted sensitivity and angular resolution of the telescope were confirmed by studies of atmospheric muon and neutrino backgrounds. We also report on the status of the analysis from AMANDA-II, a larger version with far greater capabilities. At this stage of analysis, details of the ice properties and other systematic uncertainties of the AMANDA-II telescope are under study, but we have made progress toward critical science objectives. In particular, we focus on the search for continuous emission from astrophysical point sources and the search for correlated neutrino emission from Gamma Ray Bursts detected by BATSE before decommissioning in May 2000. During the next two years, we expect to exploit the full potential of AMANDA-II with the installation of a new data acquisition system that records full waveforms from the in-ice optical sensors.

  • 211. Ahrens, J.
    et al.
    Bai, X.
    Bay, R.
    Barwick, S. W.
    Becka, T.
    Becker, J. K.
    Becker, K. -H
    Bernardini, E.
    Bertrand, D.
    Biron, A.
    Boersma, D. J.
    Böser, S.
    Botner, O.
    Bouchta, A.
    Bouhali, O.
    Burgess, T.
    Carius, Staffan
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Castermans, T.
    Chirkin, D.
    Collin, B.
    Conrad, J.
    Cooley, J.
    Cowen, D. F.
    Davour, A.
    De Clercq, C.
    DeYoung, T.
    Desiati, P.
    Dewulf, J. -P
    Ekström, P.
    Feser, T.
    Gaug, M.
    Gaisser, T. K.
    Ganugapati, R.
    Geenen, H.
    Gerhardt, L.
    Groß, A.
    Goldschmidt, A.
    Hallgren, A.
    Halzen, F.
    Hanson, K.
    Hardtke, R.
    Harenberg, T.
    Hauschildt, T.
    Helbing, K.
    Hellwig, M.
    Herquet, P.
    Hill, G. C.
    Hubert, D.
    Hughey, B.
    Hulth, P. O.
    Hultqvist, K.
    Hundertmark, S.
    Jacobsen, J.
    Karle, A.
    Kestel, M.
    Köpke, L.
    Kowalski, M.
    Kuehn, K.
    Lamoureux, J. I.
    Leich, H.
    Leuthold, M.
    Lindahl, P.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Liubarsky, I.
    Madsen, J.
    Marciniewski, P.
    Matis, H. S.
    McParland, C. P.
    Messarius, T.
    Minaeva, Y.
    Miočinović, P.
    Mock, P. C.
    Morse, R.
    Münich, K. S.
    Nam, J.
    Nahnhauer, R.
    Neunhöffer, T.
    Niessen, P.
    Nygren, D. R.
    Ögelman, H.
    Olbrechts, Ph.
    Pérez De Los Heros, C.
    Pohl, A. C.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Porrata, R.
    Price, P. B.
    Przybylski, G. T.
    Rawlins, K.
    Resconi, E.
    Rhode, W.
    Ribordy, M.
    Richter, S.
    Martino, J. R.
    Ross, D.
    Sander, H. -G
    Schinarakis, K.
    Schlenstedt, S.
    Schmidt, T.
    Schneider, D.
    Wiebusch, C. H.
    Muon track reconstruction and data selection techniques in AMANDA2004In: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, ISSN 0168-9002, E-ISSN 1872-9576, Vol. 524, no 1-3, p. 169-194Article in journal (Refereed)
    Abstract [en]

    The Antarctic Muon And Neutrino Detector Array (AMANDA) is a high-energy neutrino telescope operating at the geographic South Pole. It is a lattice of photo-multiplier tubes buried deep in the polar ice between 1500 and 2000 m. The primary goal of this detector is to discover astrophysical sources of high-energy neutrinos. A high-energy muon neutrino coming through the earth from the Northern Hemisphere can be identified by the secondary muon moving upward through the detector. The muon tracks are reconstructed with a maximum likelihood method. It models the arrival times and amplitudes of Cherenkov photons registered by the photo-multipliers. This paper describes the different methods of reconstruction, which have been successfully implemented within AMANDA. Strategies for optimizing the reconstruction performance and rejecting background are presented. For a typical analysis procedure the direction of tracks are reconstructed with about 2° accuracy. © 2004 Elsevier B.V. All rights reserved.

  • 212.
    Aikebaier, Faluke
    Linnaeus University, Faculty of Technology, Department of Physics and Electrical Engineering.
    Effects of electron-electron interaction in pristine and doped graphene2014Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    The goal of this master thesis is to investigate the eect of electron-electron interaction on electronic properties of graphene that can be measured experimentally. A tight-binding model, which includes up to next-nearest-neighbor hopping, with parameters tted to density functional theory calculations, has been used to describe the electronic structure of graphene. The electron-electron interaction is described by the Hubbard model using a mean- eld approximation. Based on the analysis of dierent tight-binding models available in the literature, we conclude that a next-nearest-neighbor tight-binding model is in better agreement with density functional theory calculations, especially for the linear dispersion around the Dirac point. The Fermi velocity in this case is very close to the experimental value, which was measured by using a variety of techniques. Interaction-induced modi cations of the linear dispersion around the Dirac point have been obtained. Unlike the non-local Hartree-Fock calculations, which take into account the long-range electron-electron interaction and yield logarithmic corrections, in agreement with experiment, we found only linear modi cations of the Fermi velocity. The reasons why one cannot obtain logarithmic corrections using the mean- eld Hubbard model have been discussed in detail. The remaining part of the thesis is focused on calculations of the local density of states around a single substitutional impurity in graphene. This quantity can be directly compared to the results of the scanning tunneling microscopy in doped graphene. We compare explicitly non-interacting and interacting cases. In the latter case, we performed self-consistent calculations, and found that electron-electron interaction has a signi cant eect on the local density of states. Furthermore, the band gap at high-symmetry points of the Brillouin zone of a supercell, triggered by the impurity, is modi ed by interactions. We use a perturbative model to explain this eect and quantitative agreement with numerical results. In conclusion, it is expected that the long-range electron-electron nteraction is extremely strong and important in graphene. However, as this thesis has shown, interactions at the level of the Hubbard model and mean- eld approximation also introduce corrections to the electronic properties of graphene.

     

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  • 213.
    Aikebaier, Faluke
    et al.
    Linnaeus University, Faculty of Technology, Department of Physics and Electrical Engineering.
    Pertsova, Anna
    Linnaeus University, Faculty of Technology, Department of Physics and Electrical Engineering.
    Canali, Carlo M.
    Linnaeus University, Faculty of Technology, Department of Physics and Electrical Engineering.
    Effects of short-range electron-electron interactions in doped graphene2015In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 92, no 15, article id 155420Article in journal (Refereed)
    Abstract [en]

    We study theoretically the effects of short-range electron-electron interactions on the electronic structure of graphene, in the presence of substitutional impurities. Our computational approach is based on the π orbital tight-binding model for graphene, with the electron-electron interactions treated self-consistently at the level of the mean-field Hubbard model. The finite impurity concentration is modeled using the supercell approach. We compare explicitly noninteracting and interacting cases with varying interaction strength and impurity potential strength. We focus in particular on the interaction-induced modifications in the local density of states around the impurity, which is a quantity that can be directly probed by scanning tunneling spectroscopy of doped graphene. We find that the resonant character of the impurity states near the Fermi level is enhanced by the interactions. Furthermore, the size of the energy gap, which opens up at high-symmetry points of the Brillouin zone of the supercell upon doping, is significantly affected by the interactions. The details of this effect depend subtly on the supercell geometry. We use a perturbative model to explain these features and find quantitative agreement with numerical results.

  • 214.
    Airey, John
    et al.
    Uppsala University.
    Berge, Maria
    Umeå University.
    That's Funny! The humorous effect of misappropriating disciplinary-specific semiotic resources2014In: The first Conference of the International Association for Cognitive Semiotics, Lund, Sweden, 25-27 Sept 2014, 2014, p. 50-51Conference paper (Refereed)
    Abstract [en]

    The socialization of disciplinary outsiders into an academic discipline has been described both in terms of becoming fluent in a disciplinary discourse (Airey, 2009; Airey & Linder, 2009; Northedge, 2002) and achieving disciplinary literacy (Airey, 2011, 2013; Geisler, 1994). In this paper we investigate disciplinary boundaries by documenting the responses of academics to a semiotic disciplinary hybrid. The hybrid we use is the Physikalisches Lied, a bogus piece of sheet music into which disciplinary-specific semiotic resources from the realm of physics have been incorporated to humorous effect.

    The piece is presented to three distinct disciplinary focus groups: physicists, musicians and a group of academics who have had little contact with either discipline. In order to elicit disciplinary responses that are free from researcher prompts, each focus group is first asked the simple, open-ended question What do you see here? Once discussion of this question is exhausted the focus groups are asked to identify as many puns as they can—essentially all the disciplinary items that they feel have been misappropriated—and to attempt to explain what this means from a disciplinary standpoint. The differences in the responses of the three groups are presented and analysed.

    We argue that semiotic material focused on by each of the three groups and the nature of the explanation offered, provide evidence of the degree of integration into the disciplines of physics and music. Our findings shed light on the process of becoming a disciplinary insider and the semiotic work involved in this process.

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  • 215.
    Airey, John
    et al.
    Linnaeus University, Faculty of Arts and Humanities, Department of Languages. Uppsala University.
    Larsson, Johanna
    Uppsala University.
    What Knowledge Do Trainee Physics Teachers Need to Learn?: Differences in the Views of Training Staff2014In: International Science Education Conference ISEC 2014, National Institute of Education, Singapore, 25-27 November, 2014, Singapore: Ministry of Education, National Institute of Education , 2014, p. 62-Conference paper (Refereed)
    Abstract [en]

    Although the impact of disciplinary differences on teaching and learning has been extensively discussed in the literature (e.g. Becher 1989; Becher and Trowler 2001; Lindblom-Ylännea et al. 2006; Neumann 2001; Neumann and Becher 2002), little research has explored this issue in relation to teacher training. In particular, we know of no work that examines differing views about the knowledge that trainee teachers need to learn across different settings. In this paper we analyse differences in the expressed views of staff involved in the training of prospective physics teachers in three environments: the education department, the physics department and schools. We analyse these differences in terms of two constructs: disciplinary literacy goals (Airey 2011, 2013) and disciplinary knowledge structures (Bernstein 1999).

    In terms of disciplinary literacy we find a stronger emphasis on learning goals for the academy expressed by informants from the physics and education departments. This can be contrasted with the view that the needs of the workplace are paramount expressed by school practitioners.

    Then, using Bernstein’s knowledge structures, we also identify clear differences in views about the nature of knowledge itself with a more hierarchical view of knowledge prevalent in the physics department and the more horizontal view of knowledge prevalent in the education department.

    The study highlights the often-conflicting signals about what constitutes useful knowledge that prospective physics teachers need to negotiate during their training. We tentatively suggest that more attention should be paid to both the theory/practice divide and potential epistemological differences in the training of prospective teachers.

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  • 216.
    Airey, John
    et al.
    Linnaeus University, Faculty of Arts and Humanities, Department of Languages. Uppsala University.
    Linder, Cedric
    Uppsala University.
    Social semiotics in university physics education: Leveraging critical constellations of disciplinary representations2015In: Science Education Research: Engaging learners for a sustainable future / [ed] Jari Lavonen, Kalle Juuti, Jarkko Lampiselkä, Anna Uitto, Kaisa Hahl, European Science Education Research Association , 2015Conference paper (Refereed)
    Abstract [en]

    Social semiotics is a broad construct where all communication is viewed as being realized through signs and their signification. In physics education we usually refer to these signs as disciplinary representations. These disciplinary representations are the semiotic resources used in physics communication, such as written and oral languages, diagrams, graphs, mathematics, apparatus and simulations. This alternative depiction of representations is used to build theory with respect to the construction and sharing of disciplinary knowledge in the teaching and learning of university physics. Based on empirical studies of physics students cooperating to explain the refraction of light, a number of theoretical constructs were developed. In this presentation we describe these constructs and examine their usefulness for problematizing teaching and learning in university physics. The theoretical constructs are: fluency in semiotic resources, disciplinary affordance and critical constellations.

    The conclusion formulates a proposal that has these constructs provide university physics teachers with a new set of meaningfully and practical tools, which will enable them to re-conceptualize their practice in ways that have the distinct potential to optimally enhance student learning.

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  • 217.
    Airey, John
    et al.
    Linnaeus University, Faculty of Arts and Humanities, Department of Languages. Uppsala University.
    Urban, Eriksson
    Uppsala University ; Kristianstad University.
    A Semiotic Analysis of the Disciplinary Affordances of the Hertzsprung-Russell Diagram in Astronomy2014In: The 5th International 360 Conference, Encompassing the multimodality of knowledge, May 8-10 2014, Aarhus University, Denmark, Aarhus: Aarhus University , 2014, p. 22-Conference paper (Refereed)
    Abstract [en]

    One of the central characteristics of disciplines is that they create their own particular ways of knowing the world through their discourse (Airey & Linder 2009). This process is facilitated by the specialization and refinement of disciplinary-specific semiotic resources over time. Nowhere is this truer than in the sciences, where it is the norm that disciplinary-specific representations have been introduced and then refined by a number of different actors (Airey 2009). As a consequence, many of the semiotic resources used in the sciences today still retain some traces of their historical roots. This makes the aquisition of disciplinary literacy (Airey, 2013) particularly problematic (see Eriksson et al. 2014 for an example from astronomy).

     In this paper we analyse one such disciplinary-specific semiotic resource from the field of Astronomy—the Hertzsprung-Russell diagram. We audit the potential of this semiotic resource to provide access to disciplinary knowledge—what Fredlund et al (2012) have termed its disciplinary affordances. Our analysis includes consideration of the use of scales, labels, symbols, sizes and colour. We show how, for historical reasons, the use of these aspects in the resource may differ from what might be expected by a newcomer to the discipline.

    We suggest that some of the issues we highlight in our analysis may, in fact, be contributors to alternative conceptions and therefore propose that lecturers pay particular attention to the disambiguation of these features for their students.

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  • 218. Akimov, D.
    et al.
    Bergstrom, L.
    Bilger, R.
    Bogoslavsky, D.
    Bolozdynya, A.
    Bondar, A.
    Calen, H.
    Carius, Staffan
    Uppsala University.
    Clement, H.
    Chernyshev, B.
    Chilingarov, A.
    Chuvilo, I.
    Dahlgren, S.
    Dunin, V.
    Ekstrom, Curt
    Fransson, K.
    Gornov, M.
    Gurov, Yu
    Gustafsson, L.
    Hirabyashi, H.
    Haggstrom, S.
    Hoistad, B.
    Ikegami, H.
    Jansson, A.
    Johansson, A.
    Kilian, K.
    Kolachev, G.
    Komogorova, L.
    Kondratyuk, L.
    Kullander, S.
    Kupsc, A.
    Kuzmin, A.
    Kuznetsov, A.
    Martemyanev, A.
    Mizuno, Y.
    Morosov, B.
    Mohn, J.
    Mortsell, A.
    Nawrot, A.
    Oelert, W.
    Pawlowski, Z.
    Povtoreiko, A.
    Purlatz, T.
    Reistad, D.
    Ruber, R.
    Rubinstein, H.
    Sandukovsky, S.
    Schuberth, U.
    Sefzick, T.
    Shafigullin, M.
    Shimizu, H.
    Shwartz, B.
    Sibirtsev, A.
    Sidrov, V.
    Sopov, V.
    Stepanaik, J.
    Sukhanov, A.
    Sukhanov, A.
    Chernyshev, V.
    Tikhomirov, V.
    Turowiecky, A.
    Trostell, B.
    Waters, M.
    Wilhelmi, Z.
    Yamamoto, A.
    Zabierowski, J.
    Zernov, A.
    Zlomanczuk, J.
    Physics with WASA and PROMICE1994In: Physics with GeV-particle beams, Juelich 1994, 1994, p. 519-530Conference paper (Refereed)
  • 219. Aliu, E.
    et al.
    Archambault, S.
    Arlen, T.
    Aune, T.
    Behera, B.
    Beilicke, M.
    Benbow, W.
    Berger, K.
    Bird, R.
    Bouvier, A.
    Buckley, J. H.
    Bugaev, V.
    Byrum, K.
    Cerruti, M.
    Chen, X.
    Ciupik, L.
    Connolly, M. P.
    Cui, W.
    Duke, C.
    Dumm, J.
    Errando, M.
    Falcone, A.
    Federici, S.
    Feng, Q.
    Finley, J. P.
    Fleischhack, H.
    Fortin, P.
    Fortson, L.
    Furniss, A.
    Galante, N.
    Gillanders, G. H.
    Griffin, S.
    Griffiths, S. T.
    Grube, J.
    Gyuk, G.
    Hanna, D.
    Holder, J.
    Hughes, G.
    Humensky, T. B.
    Johnson, C. A.
    Kaaret, P.
    Kertzman, M.
    Khassen, Y.
    Kieda, D.
    Krawczynski, H.
    Krennrich, F.
    Lang, M. J.
    Madhavan, A. S.
    Maier, G.
    Majumdar, P.
    McArthur, S.
    McCann, A.
    Meagher, K.
    Millis, J.
    Moriarty, P.
    Mukherjee, R.
    Nieto, D.
    O’Faoláin de Bhróithe, A.
    Ong, R. A.
    Otte, A. N.
    Park, N.
    Perkins, J. S.
    Pohl, M.
    Popkow, A.
    Prokoph, Heike
    DESY, Germany .
    Quinn, J.
    Ragan, K.
    Reyes, L. C.
    Reynolds, P. T.
    Richards, G. T.
    Roache, E.
    Sembroski, G. H.
    Smith, A. W.
    Staszak, D.
    Telezhinsky, I.
    Theiling, M.
    Varlotta, A.
    Vassiliev, V. V.
    Vincent, S.
    Wakely, S. P.
    Weekes, T. C.
    Weinstein, A.
    Welsing, R.
    Williams, D. A.
    Zajczyk, A.
    Zitzer, B.
    A Three-year Multi-wavelength Study of the Very-high-energy γ-Ray Blazar 1ES 0229+2002014In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 782, no 1, article id 13Article in journal (Refereed)
    Abstract [en]

    The high-frequency-peaked BL Lacertae object 1ES 0229+200 is a relatively distant (z = 0.1396), hard-spectrum (Γ ~ 2.5), very-high-energy (VHE; E > 100 GeV) emitting γ-ray blazar. VHE measurements of this active galactic nucleus have been used to place constraints on the intensity of the extragalactic background light and the intergalactic magnetic field (IGMF). A multi-wavelength study of this object centered around VHE observations by Very Energetic Radiation Imaging Telescope Array System (VERITAS) is presented. This study obtained, over a period of three years, an 11.7 standard deviation detection and an average integral flux F(E > 300 GeV) = (23.3 ± 2.8stat ± 5.8sys× 10–9 photons m–2 s–1, or 1.7% of the Crab Nebula's flux (assuming the Crab Nebula spectrum measured by H.E.S.S). Supporting observations from Swift and RXTE are analyzed. TheSwift observations are combined with previously published Fermi observations and the VHE measurements to produce an overall spectral energy distribution which is then modeled assuming one-zone synchrotron-self-Compton emission. The χ2probability of the TeV flux being constant is 1.6%. This, when considered in combination with measured variability in the X-ray band, and the demonstrated variability of many TeV blazars, suggests that the use of blazars such as 1ES 0229+200 for IGMF studies may not be straightforward and challenges models that attribute hard TeV spectra to secondary γ-ray production along the line of sight.

  • 220. Aliu, E.
    et al.
    Archambault, S.
    Arlen, T.
    Aune, T.
    Beilicke, M.
    Benbow, W.
    Bird, R.
    Bouvier, A.
    Bradbury, S. M.
    Buckley, J. H.
    Bugaev, V.
    Byrum, K.
    Cannon, A.
    Cesarini, A.
    Ciupik, L.
    Collins-Hughes, E.
    Connolly, M. P.
    Cui, W.
    Dickherber, R.
    Duke, C.
    Dumm, J.
    Dwarkadas, V. V.
    Errando, M.
    Falcone, A.
    Federici, S.
    Feng, Q.
    Finley, J. P.
    Finnegan, G.
    Fortson, L.
    Furniss, A.
    Galante, N.
    Gall, D.
    Gillanders, G. H.
    Godambe, S.
    Gotthelf, E. V.
    Griffin, S.
    Grube, J.
    Gyuk, G.
    Hanna, D.
    Holder, J.
    Huan, H.
    Hughes, G.
    Humensky, T. B.
    Kaaret, P.
    Karlsson, N.
    Kertzman, M.
    Khassen, Y.
    Kieda, D.
    Krawczynski, H.
    Krennrich, F.
    Lang, M. J.
    Lee, K.
    Madhavan, A. S.
    Maier, G.
    Majumdar, P.
    McArthur, S.
    McCann, A.
    Millis, J.
    Moriarty, P.
    Mukherjee, R.
    Nelson, T.
    O’Faoláin de Bhróithe, A.
    Ong, R. A.
    Orr, M.
    Otte, A. N.
    Pandel, D.
    Park, N.
    Perkins, J. S.
    Pohl, M.
    Popkow, A.
    Prokoph, Heike
    DESY, Germany .
    Quinn, J.
    Ragan, K.
    Reyes, L. C.
    Reynolds, P. T.
    Roache, E.
    Rose, H. J.
    Ruppel, J.
    Saxon, D. B.
    Schroedter, M.
    Sembroski, G. H.
    \c Sentürk, G. D.
    Skole, C.
    Telezhinsky, I.
    Tesić, G.
    Theiling, M.
    Thibadeau, S.
    Tsurusaki, K.
    Tyler, J.
    Varlotta, A.
    Vassiliev, V. V.
    Vincent, S.
    Wakely, S. P.
    Ward, J. E.
    Weekes, T. C.
    Weinstein, A.
    Weisgarber, T.
    Welsing, R.
    Williams, D. A.
    Zitzer, B.
    Discovery of TeV Gamma-Ray Emission toward Supernova Remnant SNR G78.2+2.12013In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, \apj, Vol. 770, no 2, article id 93Article in journal (Refereed)
    Abstract [en]

    We report the discovery of an unidentified, extended source of very-high-energy gamma-ray emission, VER J2019+407, within the radio shell of the supernova remnant SNR G78.2+2.1, using 21.4 hr of data taken by the VERITAS gamma-ray observatory in 2009. These data confirm the preliminary indications of gamma-ray emission previously seen in a two-year (2007-2009) blind survey of the Cygnus region by VERITAS. VER J2019+407, which is detected at a post-trials significance of 7.5 standard deviations in the 2009 data, is localized to the northwestern rim of the remnant in a region of enhanced radio and X-ray emission. It has an intrinsic extent of  and its spectrum is well-characterized by a differential power law (dN/dE = N 0 × (E/TeV)–Γ) with a photon index of Γ = 2.37 ± 0.14stat ± 0.20sys and a flux normalization of N 0 = 1.5 ± 0.2stat ± 0.4sys × 10–12 photon TeV–1 cm–2 s–1. This yields an integral flux of 5.2 ± 0.8stat ± 1.4sys × 10–12 photon cm–2 s–1above 320 GeV, corresponding to 3.7% of the Crab Nebula flux. We consider the relationship of the TeV gamma-ray emission with the GeV gamma-ray emission seen from SNR G78.2+2.1 as well as that seen from a nearby cocoon of freshly accelerated cosmic rays. Multiple scenarios are considered as possible origins for the TeV gamma-ray emission, including hadronic particle acceleration at the SNR shock.

  • 221. Aliu, E.
    et al.
    Archambault, S.
    Arlen, T.
    Aune, T.
    Beilicke, M.
    Benbow, W.
    Bird, R.
    Bouvier, A.
    Buckley, J. H.
    Bugaev, V.
    Cesarini, A.
    Ciupik, L.
    Connolly, M. P.
    Cui, W.
    Dumm, J.
    Errando, M.
    Falcone, A.
    Federici, S.
    Feng, Q.
    Finley, J. P.
    Fortin, P.
    Fortson, L.
    Furniss, A.
    Galante, N.
    Gérard, L.
    Gillanders, G. H.
    Griffin, S.
    Grube, J.
    Gyuk, G.
    Hanna, D.
    Holder, J.
    Hughes, G.
    Humensky, T. B.
    Kaaret, P.
    Kertzman, M.
    Khassen, Y.
    Kieda, D.
    Krawczynski, H.
    Krennrich, F.
    Lang, M. J.
    Madhavan, A. S.
    Maier, G.
    Majumdar, P.
    McArthur, S.
    McCann, A.
    Moriarty, P.
    Mukherjee, R.
    Nieto, D.
    O’Faoláin de Bhróithe, A.
    Ong, R. A.
    Orr, M.
    Otte, A. N.
    Park, N.
    Perkins, J. S.
    Pohl, M.
    Popkow, A.
    Prokoph, Heike
    DESY, Germany.
    Quinn, J.
    Ragan, K.
    Reyes, L. C.
    Reynolds, P. T.
    Richards, G. T.
    Roache, E.
    Saxon, D. B.
    Sembroski, G. H.
    Skole, C.
    Smith, A. W.
    Soares-Furtado, M.
    Staszak, D.
    Telezhinsky, I.
    Te\v sić, G.
    Theiling, M.
    Varlotta, A.
    Vassiliev, V. V.
    Vincent, S.
    Wakely, S. P.
    Weekes, T. C.
    Weinstein, A.
    Welsing, R.
    Williams, D. A.
    Zitzer, B.
    Collaboration, V E R I T A S
    Böttcher, M.
    Fumagalli, M.
    Jadhav, J.
    Long Term Observations of B2 1215+30 with VERITAS2013In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 779, no 2, article id 92Article in journal (Refereed)
    Abstract [en]

    We report on VERITAS observations of the BL Lac object B2 1215+30 between 2008 and 2012. During this period, the source was detected at very high energies (VHEs; E > 100 GeV) by VERITAS with a significance of 8.9s and showed clear variability on timescales larger than months. In 2011, the source was found to be in a relatively bright state and a power-law fit to the differential photon spectrum yields a spectral index of 3.6 +/- 0.4(stat) +/- 0.3(syst) withan integral flux above 200 GeV of (8.0 +/- 0.9(stat) +/- 3.2(syst)) x 10(-12) cm(-2) s(-1). No short term variability could be detected during the bright state in 2011. Multi-wavelength data were obtained contemporaneously with the VERITAS observations in 2011 and cover optical (Super-LOTIS, MDM, Swift/UVOT), X-ray (Swift/XRT), and gamma-ray (Fermi-LAT) frequencies. These were used to construct the spectral energy distribution (SED) of B2 1215+30. A one-zone leptonic model is used to model the blazar emission and the results are compared to those of MAGIC from early 2011 and other VERITAS-detected blazars. The SED can be reproduced well with model parameters typical for VHE-detected BL Lac objects.

  • 222. Aliu, E.
    et al.
    Archambault, S.
    Arlen, T.
    Aune, T.
    Beilicke, M.
    Benbow, W.
    Bird, R.
    Böttcher, M.
    Bouvier, A.
    Bugaev, V.
    Byrum, K.
    Cesarini, A.
    Ciupik, L.
    Collins-Hughes, E.
    Connolly, M. P.
    Cui, W.
    Dickherber, R.
    Duke, C.
    Dumm, J.
    Errando, M.
    Falcone, A.
    Federici, S.
    Feng, Q.
    Finley, J. P.
    Finnegan, G.
    Fortson, L.
    Furniss, A.
    Galante, N.
    Gall, D.
    Gillanders, G. H.
    Griffin, S.
    Grube, J.
    Gyuk, G.
    Hanna, D.
    Holder, J.
    Hughes, G.
    Humensky, T. B.
    Kaaret, P.
    Kertzman, M.
    Khassen, Y.
    Kieda, D.
    Krawczynski, H.
    Krennrich, F.
    Lang, M. J.
    Madhavan, A. S.
    Maier, G.
    Majumdar, P.
    McArthur, S.
    McCann, A.
    Moriarty, P.
    Mukherjee, R.
    Nelson, T.
    O’Faoláin de Bhróithe, A.
    Ong, R. A.
    Orr, M.
    Otte, A. N.
    Park, N.
    Perkins, J. S.
    Pichel, A.
    Pohl, M.
    Popkow, A.
    Prokoph, Heike
    DESY, Germany.
    Quinn, J.
    Ragan, K.
    Reyes, L. C.
    Reynolds, P. T.
    Roache, E.
    Saxon, D. B.
    Schroedter, M.
    Sembroski, G. H.
    Skole, C.
    Smith, A. W.
    Staszak, D.
    Telezhinsky, I.
    Theiling, M.
    Tyler, J.
    Varlotta, A.
    Vassiliev, V. V.
    Wakely, S. P.
    Weekes, T. C.
    Weinstein, A.
    Welsing, R.
    Williams, D. A.
    Zitzer, B.
    Multiwavelength Observations and Modeling of 1ES 1959+650 in a Low Flux State2013In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 775, no 1, article id 3Article in journal (Refereed)
    Abstract [en]

    We report on the VERITAS observations of the high-frequency peaked BL Lac object 1ES 1959+650 in the period 2007-2011. This source is detected at TeV energies by VERITAS at 16.4 standard deviation (σ) significance in 7.6 hr of observation in a low flux state. A multiwavelength spectral energy distribution (SED) is constructed from contemporaneous data from VERITAS,Fermi-LAT, RXTE PCA, and Swift UVOT. Swift XRT data is not included in the SED due to a lack of simultaneous observations with VERITAS. In contrast to the orphan γ-ray flare exhibited by this source in 2002, the X-ray flux of the source is found to vary by an order of magnitude, while other energy regimes exhibit less variable emission. A quasi-equilibrium synchrotron self-Compton model with an additional external radiation field is used to describe three SEDs corresponding to the lowest, highest, and average X-ray states. The variation in the X-ray spectrum is modeled by changing the electron injection spectral index, with minor adjustments of the kinetic luminosity in electrons. This scenario produces small-scale flux variability of the order of  2 in the high energy (E > 1 MeV) and very high energy (E > 100 GeV) γ-ray regimes, which is corroborated by the Fermi-LAT, VERITAS, and Whipple 10 m telescope light curves.

  • 223. Aliu, E.
    et al.
    Archambault, S.
    Arlen, T.
    Aune, T.
    Beilicke, M.
    Benbow, W.
    Bouvier, A.
    Bradbury, S. M.
    Buckley, J. H.
    Bugaev, V.
    Byrum, K.
    Cannon, A.
    Cesarini, A.
    Christiansen, J. L.
    Ciupik, L.
    Collins-Hughes, E.
    Connolly, M. P.
    Cui, W.
    Decerprit, G.
    Dickherber, R.
    Dumm, J.
    Errando, M.
    Falcone, A.
    Feng, Q.
    Ferrer, F.
    Finley, J. P.
    Finnegan, G.
    Fortson, L.
    Furniss, A.
    Galante, N.
    Gall, D.
    Godambe, S.
    Griffin, S.
    Grube, J.
    Gyuk, G.
    Hanna, D.
    Holder, J.
    Huan, H.
    Hughes, G.
    Humensky, T. B.
    Kaaret, P.
    Karlsson, N.
    Kertzman, M.
    Khassen, Y.
    Kieda, D.
    Krawczynski, H.
    Krennrich, F.
    Lee, K.
    Madhavan, A. S.
    Maier, G.
    Majumdar, P.
    McArthur, S.
    McCann, A.
    Moriarty, P.
    Mukherjee, R.
    Ong, R. A.
    Orr, M.
    Otte, A. N.
    Park, N.
    Perkins, J. S.
    Pohl, M.
    Prokoph, Heike
    DESY, Germany.
    Quinn, J.
    Ragan, K.
    Reyes, L. C.
    Reynolds, P. T.
    Roache, E.
    Rose, H. J.
    Ruppel, J.
    Saxon, D. B.
    Schroedter, M.
    Sembroski, G. H.
    \c Sentürk, G. D.
    Skole, C.
    Smith, A. W.
    Staszak, D.
    Telezhinsky, I.
    Te\v sić, G.
    Theiling, M.
    Thibadeau, S.
    Tsurusaki, K.
    Varlotta, A.
    Vassiliev, V. V.
    Vincent, S.
    Vivier, M.
    Wagner, R. G.
    Wakely, S. P.
    Ward, J. E.
    Weekes, T. C.
    Weinstein, A.
    Weisgarber, T.
    Williams, D. A.
    Zitzer, B.
    VERITAS deep observations of the dwarf spheroidal galaxy Segue 12012In: Physical Review D, ISSN 1550-7998, E-ISSN 1550-2368, Vol. 85, no 6, article id 062001Article in journal (Refereed)
    Abstract [en]

    The VERITAS array of Cherenkov telescopes has carried out a deep observational program on the nearby dwarf spheroidal galaxy Segue 1. We report on the results of nearly 48 hours of good quality selected data, taken between January 2010 and May 2011. No significant γ-ray emission is detected at the nominal position of Segue 1, and upper limits on the integrated flux are derived. According to recent studies, Segue 1 is the most dark matter-dominated dwarf spheroidal galaxy currently known. We derive stringent bounds on various annihilating and decaying dark matter particle models. The upper limits on the velocity-weighted annihilation cross-section are ⟨σv⟩95% CL≲10−23  cm3 s−1, improving our limits from previous observations of dwarf spheroidal galaxies by at least a factor of 2 for dark matter particle masses mχ≳300  GeV. The lower limits on the decay lifetime are at the level of τ95% CL≳1024  s. Finally, we address the interpretation of the cosmic ray lepton anomalies measured by ATIC and PAMELA in terms of dark matter annihilation, and show that the VERITAS observations of Segue 1 disfavor such a scenario.

  • 224. Aliu, E.
    et al.
    Archambault, S.
    Arlen, T.
    Aune, T.
    Beilicke, M.
    Benbow, W.
    Bouvier, A.
    Bradbury, S. M.
    Buckley, J. H.
    Bugaev, V.
    Byrum, K.
    Cannon, A.
    Cesarini, A.
    Ciupik, L.
    Collins-Hughes, E.
    Connolly, M. P.
    Cui, W.
    Decerprit, G.
    Dickherber, R.
    Duke, C.
    Dumm, J.
    Dwarkadas, V. V.
    Errando, M.
    Falcone, A.
    Feng, Q.
    Finley, J. P.
    Finnegan, G.
    Fortson, L.
    Furniss, A.
    Galante, N.
    Gall, D.
    Godambe, S.
    Griffin, S.
    Grube, J.
    Gyuk, G.
    Hanna, D.
    Holder, J.
    Huan, H.
    Hughes, G.
    Humensky, T. B.
    Kaaret, P.
    Karlsson, N.
    Kertzman, M.
    Khassen, Y.
    Kieda, D.
    Krawczynski, H.
    Krennrich, F.
    Lang, M. J.
    Lee, K.
    Maier, G.
    Majumdar, P.
    McArthur, S.
    McCann, A.
    Millis, J.
    Moriarty, P.
    Mukherjee, R.
    Nuñez, P. D.
    Ong, R. A.
    Orr, M.
    Otte, A. N.
    Pandel, D.
    Park, N.
    Perkins, J. S.
    Pohl, M.
    Prokoph, Heike
    DESY, Germany .
    Quinn, J.
    Ragan, K.
    Reyes, L. C.
    Reynolds, P. T.
    Roache, E.
    Rose, H. J.
    Ruppel, J.
    Saxon, D. B.
    Schroedter, M.
    Sembroski, G. H.
    Skole, C.
    Smith, A. W.
    Staszak, D.
    Telezhinsky, I.
    Tesić, G.
    Theiling, M.
    Thibadeau, S.
    Tsurusaki, K.
    Tyler, J.
    Varlotta, A.
    Vincent, S.
    Vivier, M.
    Wakely, S. P.
    Ward, J. E.
    Weekes, T. C.
    Weinstein, A.
    Weisgarber, T.
    Welsing, R.
    Williams, D. A.
    Zitzer, B.
    VERITAS Observations of the Nova in V407 Cygni2012In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, \apj, Vol. 754, no 1, article id 77Article in journal (Refereed)
    Abstract [en]

    We report on very high energy (E > 100 GeV) gamma-ray observations of V407 Cygni, a symbiotic binary that underwent a nova outburst producing 0.1-10 GeV gamma rays during 2010 March 10-26. Observations were made with the Very Energetic Radiation Imaging Telescope Array System during 2010 March 19-26 at relatively large zenith angles due to the position of V407 Cyg. An improved reconstruction technique for large zenith angle observations is presented and used to analyze the data. We do not detect V407 Cygni and place a differential upper limit on the flux at 1.6 TeV of 2.3 × 10–12 erg cm–2 s–1 (at the 95% confidence level). When considered jointly with data from Fermi-LAT, this result places limits on the acceleration of very high energy particles in the nova.

  • 225. Aliu, E.
    et al.
    Archambault, S.
    Arlen, T.
    Aune, T.
    Beilicke, M.
    Benbow, W.
    Bouvier, A.
    Buckley, J. H.
    Bugaev, V.
    Byrum, K.
    Cesarini, A.
    Ciupik, L.
    Collins-Hughes, E.
    Connolly, M. P.
    Cui, W.
    Dickherber, R.
    Duke, C.
    Dumm, J.
    Falcone, A.
    Federici, S.
    Feng, Q.
    Finley, J. P.
    Finnegan, G.
    Fortson, L.
    Furniss, A.
    Galante, N.
    Gall, D.
    Gillanders, G. H.
    Godambe, S.
    Griffin, S.
    Grube, J.
    Gyuk, G.
    Hanna, D.
    Holder, J.
    Huan, H.
    Hughes, G.
    Humensky, T. B.
    Kaaret, P.
    Karlsson, N.
    Khassen, Y.
    Kieda, D.
    Krawczynski, H.
    Krennrich, F.
    Lang, M. J.
    LeBohec, S.
    Lee, K.
    Lyutikov, M.
    Madhavan, A. S.
    Maier, G.
    Majumdar, P.
    McArthur, S.
    McCann, A.
    Moriarty, P.
    Mukherjee, R.
    Nelson, T.
    O’Faoláin de Bhróithe, A.
    Ong, R. A.
    Orr, M.
    Otte, A. N.
    Park, N.
    Perkins, J. S.
    Pohl, M.
    Prokoph, Heike
    DESY, Germany .
    Quinn, J.
    Ragan, K.
    Reyes, L. C.
    Reynolds, P. T.
    Roache, E.
    Saxon, D. B.
    Schroedter, M.
    Sembroski, G. H.
    Sentürk, G. D.
    Smith, A. W.
    Staszak, D.
    Telezhinsky, I.
    Te\v sić, G.
    Theiling, M.
    Thibadeau, S.
    Tsurusaki, K.
    Varlotta, A.
    Vincent, S.
    Vivier, M.
    Wagner, R. G.
    Wakely, S. P.
    Weekes, T. C.
    Weinstein, A.
    Welsing, R.
    Williams, D. A.
    Zitzer, B.
    Kondratiev, V.
    Search for a Correlation between Very-high-energy Gamma Rays and Giant Radio Pulses in the Crab Pulsar2012In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 760, no 2, article id 136Article in journal (Refereed)
    Abstract [en]

    We present the results of a joint observational campaign between the Green Bank radio telescope and the VERITAS gamma-ray telescope, which searched for a correlation between the emission of very-high-energy (VHE) gamma rays (E γ > 150 GeV) and giant radio pulses (GRPs) from the Crab pulsar at 8.9 GHz. A total of 15,366 GRPs were recorded during 11.6 hr of simultaneous observations, which were made across four nights in 2008 December and in 2009 November and December. We searched for an enhancement of the pulsed gamma-ray emission within time windows placed around the arrival time of the GRP events. In total, eight different time windows with durations ranging from 0.033 ms to 72 s were positioned at three different locations relative to the GRP to search for enhanced gamma-ray emission which lagged, led, or was concurrent with, the GRP event. Furthermore, we performed separate searches on main pulse GRPs and interpulse GRPs and on the most energetic GRPs in our data sample. No significant enhancement of pulsed VHE emission was found in any of the preformed searches. We set upper limits of 5-10 times the average VHE flux of the Crab pulsar on the flux simultaneous with interpulse GRPs on single-rotation-period timescales. On ~8 s timescales around interpulse GRPs, we set an upper limit of 2-3 times the average VHE flux. Within the framework of recent models for pulsed VHE emission from the Crab pulsar, the expected VHE-GRP emission correlations are below the derived limits.

  • 226. Aliu, E.
    et al.
    Archambault, S.
    Arlen, T.
    Aune, T.
    Beilicke, M.
    Benbow, W.
    Bouvier, A.
    Buckley, J. H.
    Bugaev, V.
    Cesarini, A.
    Ciupik, L.
    Collins-Hughes, E.
    Connolly, M. P.
    Cui, W.
    Dickherber, R.
    Duke, C.
    Dumm, J.
    Dwarkadas, V. V.
    Errando, M.
    Falcone, A.
    Federici, S.
    Feng, Q.
    Finley, J. P.
    Finnegan, G.
    Fortson, L.
    Furniss, A.
    Galante, N.
    Gall, D.
    Gillanders, G. H.
    Godambe, S.
    Gotthelf, E. V.
    Griffin, S.
    Grube, J.
    Gyuk, G.
    Hanna, D.
    Holder, J.
    Hughes, G.
    Humensky, T. B.
    Kaaret, P.
    Kargaltsev, O.
    Karlsson, N.
    Khassen, Y.
    Kieda, D.
    Krawczynski, H.
    Krennrich, F.
    Lang, M. J.
    Lee, K.
    Madhavan, A. S.
    Maier, G.
    Majumdar, P.
    McArthur, S.
    McCann, A.
    Moriarty, P.
    Mukherjee, R.
    Nelson, T.
    O’Faoláin de Bhróithe, A.
    Ong, R. A.
    Orr, M.
    Otte, A. N.
    Park, N.
    Perkins, J. S.
    Pohl, M.
    Prokoph, Heike
    DESY, Germany.
    Quinn, J.
    Ragan, K.
    Reyes, L. C.
    Reynolds, P. T.
    Roache, E.
    Roberts, M.
    Saxon, D. B.
    Schroedter, M.
    Sembroski, G. H.
    Slane, P.
    Smith, A. W.
    Staszak, D.
    Telezhinsky, I.
    Tesić, G.
    Theiling, M.
    Thibadeau, S.
    Tsurusaki, K.
    Tyler, J.
    Varlotta, A.
    Vassiliev, V. V.
    Vincent, S.
    Vivier, M.
    Wakely, S. P.
    Weekes, T. C.
    Weinstein, A.
    Welsing, R.
    Williams, D. A.
    Zitzer, B.
    Discovery of TeV Gamma-Ray Emission from CTA 1 by VERITAS2013In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 764, no 1, article id 38Article in journal (Refereed)
    Abstract [en]

    We report the discovery of TeV gamma-ray emission coincident with the shell-type radio supernova remnant (SNR) CTA 1 using the VERITAS gamma-ray observatory. The source, VER J0006+729, was detected as a 6.5 standard deviation excess over background and shows an extended morphology, approximated by a two-dimensional Gaussian of semimajor (semiminor) axis 030 (024) and a centroid 5' from the Fermi gamma-ray pulsar PSR J0007+7303 and its X-ray pulsar wind nebula (PWN). The photon spectrum is well described by a power-law dN/dE = N 0(E/3 TeV)–Γ, with a differential spectral index of Γ = 2.2 ± 0.2stat ± 0.3sys, and normalization N 0 = (9.1 ± 1.3stat ± 1.7sys× 10–14 cm–2 s–1 TeV–1. The integral flux, F γ = 4.0 ×10–12 erg cm–2 s–1 above 1 TeV, corresponds to 0.2% of the pulsar spin-down power at 1.4 kpc. The energetics, colocation with the SNR, and the relatively small extent of the TeV emission strongly argue for the PWN origin of the TeV photons. We consider the origin of the TeV emission in CTA 1.

  • 227. Aliu, E.
    et al.
    Archambault, S.
    Arlen, T.
    Aune, T.
    Beilicke, M.
    Benbow, W.
    Böttcher, M.
    Bouvier, A.
    Bradbury, S. M.
    Buckley, J. H.
    Bugaev, V.
    Byrum, K.
    Cannon, A.
    Cesarini, A.
    Ciupik, L.
    Collins-Hughes, E.
    Connolly, M. P.
    Coppi, P.
    Cui, W.
    Decerprit, G.
    Dickherber, R.
    Dumm, J.
    Errando, M.
    Falcone, A.
    Feng, Q.
    Finley, J. P.
    Finnegan, G.
    Fortson, L.
    Furniss, A.
    Galante, N.
    Gall, D.
    Godambe, S.
    Griffin, S.
    Grube, J.
    Gyuk, G.
    Hanna, D.
    Hawkins, K.
    Holder, J.
    Huan, H.
    Hughes, G.
    Humensky, T. B.
    Kaaret, P.
    Karlsson, N.
    Kertzman, M.
    Khassen, Y.
    Kieda, D.
    Krawczynski, H.
    Krennrich, F.
    Lang, M. J.
    Lee, K.
    Madhavan, A. S.
    Maier, G.
    Majumdar, P.
    McArthur, S.
    McCann, A.
    Moriarty, P.
    Mukherjee, R.
    Ong, R. A.
    Orr, M.
    Otte, A. N.
    Palma, N.
    Park, N.
    Perkins, J. S.
    Pichel, A.
    Pohl, M.
    Prokoph, Heike
    DESY, Germany.
    Quinn, J.
    Ragan, K.
    Reyes, L. C.
    Reynolds, P. T.
    Roache, E.
    Rose, H. J.
    Ruppel, J.
    Saxon, D. B.
    Schroedter, M.
    Sembroski, G. H.
    \c Sentürk, G. D.
    Smith, A. W.
    Staszak, D.
    Telezhinsky, I.
    Tesić, G.
    Theiling, M.
    Thibadeau, S.
    Tsurusaki, K.
    Varlotta, A.
    Vivier, M.
    Wakely, S. P.
    Ward, J. E.
    Weekes, T. C.
    Weinstein, A.
    Weisgarber, T.
    Williams, D. A.
    Zitzer, B.
    Fortin, P.
    Horan, D.
    Discovery of High-energy and Very High Energy γ-Ray Emission from the Blazar RBS 04132012In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 750, no 2, article id 94Article in journal (Refereed)
    Abstract [en]

    We report on the discovery of high-energy (HE; E > 0.1 GeV) and very high energy (VHE; E > 100 GeV) γ-ray emission from the high-frequency-peaked BL Lac object RBS 0413. VERITAS, a ground-based γ-ray observatory, detected VHE γ rays from RBS 0413 with a statistical significance of 5.5 standard deviations (σ) and a γ-ray flux of (1.5 ± 0.6stat ± 0.7syst× 10–8 photons m–2 s–1 (~1% of the Crab Nebula flux) above 250 GeV. The observed spectrum can be described by a power law with a photon index of 3.18 ± 0.68stat ± 0.30syst. Contemporaneous observations with the Large Area Telescope (LAT) on the Fermi Gamma-ray Space Telescope detected HE γ rays from RBS 0413 with a statistical significance of more than 9σ, a power-law photon index of 1.57 ± 0.12stat +0.11 – 0.12sys, and a γ-ray flux between 300 MeV and 300 GeV of (1.64 ± 0.43stat +0.31 – 0.22sys× 10–5photons m–2 s–1. We present the results from Fermi-LAT and VERITAS, including a spectral energy distribution modeling of the γ-ray, quasi-simultaneous X-ray (Swift-XRT), ultraviolet (Swift-UVOT), and R-band optical (MDM) data. We find that, if conditions close to equipartition are required, both the combined synchrotron self-Compton/external-Compton and the lepto-hadronic models are preferred over a pure synchrotron self-Compton model.

  • 228. Aliu, E.
    et al.
    Archambault, S.
    Arlen, T.
    Aune, T.
    Beilicke, M.
    Benbow, W.
    Böttcher, M.
    Bouvier, A.
    Buckley, J. H.
    Bugaev, V.
    Cesarini, A.
    Ciupik, L.
    Collins-Hughes, E.
    Connolly, M. P.
    Cui, W.
    Dickherber, R.
    Duke, C.
    Dumm, J.
    Errando, M.
    Falcone, A.
    Federici, S.
    Feng, Q.
    Finley, J. P.
    Finnegan, G.
    Fortson, L.
    Furniss, A.
    Galante, N.
    Gall, D.
    Godambe, S.
    Griffin, S.
    Grube, J.
    Gyuk, G.
    Hanna, D.
    Holder, J.
    Huan, H.
    Kaaret, P.
    Karlsson, N.
    Khassen, Y.
    Kieda, D.
    Krawczynski, H.
    Krennrich, F.
    Lee, K.
    Madhavan, A. S.
    Maier, G.
    Majumdar, P.
    McArthur, S.
    McCann, A.
    Moriarty, P.
    Mukherjee, R.
    Nelson, T.
    O’Faoláin de Bhróithe, A.
    Ong, R. A.
    Orr, M.
    Otte, A. N.
    Park, N.
    Perkins, J. S.
    Pichel, A.
    Pohl, M.
    Prokoph, Heike
    DESY, Germany .
    Quinn, J.
    Ragan, K.
    Reyes, L. C.
    Reynolds, P. T.
    Roache, E.
    Saxon, D. B.
    Sembroski, G. H.
    Staszak, D.
    Telezhinsky, I.
    Tesić, G.
    Theiling, M.
    Thibadeau, S.
    Tsurusaki, K.
    Varlotta, A.
    Vassiliev, V. V.
    Vincent, S.
    Vivier, M.
    Wakely, S. P.
    Weekes, T. C.
    Weinstein, A.
    Welsing, R.
    Williams, D. A.
    Zitzer, B.
    Collaboration, V E R I T A S
    Fortin, P.
    Horan, D.
    Fumagalli, M.
    Kaplan, K.
    Prochaska, J. X.
    VERITAS Observations of Six Bright, Hard-spectrum Fermi-LAT Blazars2012In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 759, no 2, article id 102Article in journal (Refereed)
    Abstract [en]

    We report on VERITAS very high energy (VHE; E ≥ 100 GeV) observations of six blazars selected from the Fermi Large Area Telescope First Source Catalog (1FGL). The gamma-ray emission from 1FGL sources was extrapolated up to the VHE band, taking gamma-ray absorption by the extragalactic background light into account. This allowed the selection of six bright, hard-spectrum blazars that were good candidate TeV emitters. Spectroscopic redshift measurements were attempted with the Keck Telescope for the targets without Sloan Digital Sky Survey spectroscopic data. No VHE emission is detected during the observations of the six sources described here. Corresponding TeV upper limits are presented, along with contemporaneousFermi observations and non-concurrent Swift UVOT and X-Ray Telescope data. The blazar broadband spectral energy distributions (SEDs) are assembled and modeled with a single-zone synchrotron self-Compton model. The SED built for each of the six blazars shows a synchrotron peak bordering between the intermediate- and high-spectrum-peak classifications, with four of the six resulting in particle-dominated emission regions.

  • 229. Aliu, E.
    et al.
    Archambault, S.
    Aune, T.
    Behera, B.
    Beilicke, M.
    Benbow, W.
    Berger, K.
    Bird, R.
    Bouvier, A.
    Buckley, J. H.
    Bugaev, V.
    Byrum, K.
    Cerruti, M.
    Chen, X.
    Ciupik, L.
    Connolly, M. P.
    Cui, W.
    Duke, C.
    Dumm, J.
    Errando, M.
    Falcone, A.
    Federici, S.
    Feng, Q.
    Finley, J. P.
    Fortin, P.
    Fortson, L.
    Furniss, A.
    Galante, N.
    Gillanders, G. H.
    Griffin, S.
    Griffiths, S. T.
    Grube, J.
    Gyuk, G.
    Hanna, D.
    Holder, J.
    Hughes, G.
    Humensky, T. B.
    Kaaret, P.
    Kertzman, M.
    Khassen, Y.
    Kieda, D.
    Krawczynski, H.
    Krennrich, F.
    Lang, M. J.
    Madhavan, A. S.
    Maier, G.
    Majumdar, P.
    McCann, A.
    Moriarty, P.
    Mukherjee, R.
    Nieto, D.
    de Bhroithe, A. O'Faolain
    Ong, R. A.
    Otte, A. N.
    Park, N.
    Perkins, J. S.
    Pohl, M.
    Popkow, A.
    Prokoph, Heike
    Quinn, J.
    Ragan, K.
    Rajotte, J.
    Reyes, L. C.
    Reynolds, P. T.
    Richards, G. T.
    Roache, E.
    Rousselle, J.
    Sembroski, G. H.
    Sheidaei, F.
    Skole, C.
    Smith, A. W.
    Staszak, D.
    Stroh, M.
    Telezhinsky, I.
    Theiling, M.
    Tucci, J. V.
    Tyler, J.
    Varlotta, A.
    Vincent, S.
    Wakely, S. P.
    Weinstein, A.
    Welsing, R.
    Williams, D. A.
    Zajczyk, A.
    Zitzer, B.
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    Anton, G.
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    Heidelberg Univ, Germany.
    Tjus, J. Becker
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    Punch, Michael
    niv Paris Diderot, APC, AstroParticule & Cosmology, CNRS,IN2P3,CEA,Irfu, Observ Paris,Sorbonne Paris C, 10 Rue Alice Domon & Leonie Duquet, F-75205 Paris 13, France.
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    Zech, A.
    Zechlin, H. -S
    Long-term TeV and X-ray Observations of the Gamma-ray Binary HESS J0632+0572014In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 780, no 2, article id 168Article in journal (Refereed)
    Abstract [en]

    HESS J0632+057 is the only gamma-ray binary known so far whose position in the sky allows observations with ground-based observatories in both thenorthern and southern hemispheres. Here we report on long-term observations of HESS J0632+057 conducted with the Very Energetic Radiation Imaging Telescope Array System and High Energy Stereoscopic System Cherenkov telescopes and the X-ray satellite Swift, spanning a time range from 2004 to 2012 and covering most of the system's orbit. The very-high-energy (VHE) emission is found to be variable and is correlated with that at X-ray energies. An orbital period of 315(-4)(+6) days is derived from the X-ray data set, which is compatible with previous results, P = (321 +/- 5) days. The VHE light curve shows a distinct maximum at orbital phases close to 0.3, or about 100 days after periastron passage, which coincides with the periodic enhancement of the X-rayemission. Furthermore, the analysis of the TeV data shows for the first time a statistically significant (> 6.5 sigma) detection at orbital phases 0.6-0.9. Theobtained gamma-ray and X-ray light curves and the correlation of the source emission at these two energy bands are discussed in the context of the recent ephemeris obtained for the system. Our results are compared to those reported for other gamma-ray binaries.

  • 230. Aliu, E.
    et al.
    Archambault, S.
    Aune, T.
    Behera, B.
    Beilicke, M.
    Benbow, W.
    Berger, K.
    Bird, R.
    Buckley, J. H.
    Bugaev, V.
    Cardenzana, J. V.
    Cerruti, M.
    Chen, X.
    Ciupik, L.
    Collins-Hughes, E.
    Connolly, M. P.
    Cui, W.
    Dumm, J.
    Dwarkadas, V. V.
    Errando, M.
    Falcone, A.
    Federici, S.
    Feng, Q.
    Finley, J. P.
    Fleischhack, H.
    Fortin, P.
    Fortson, L.
    Furniss, A.
    Galante, N.
    Gall, D.
    Gillanders, G. H.
    Griffin, S.
    Griffiths, S. T.
    Grube, J.
    Gyuk, G.
    Hanna, D.
    Holder, J.
    Hughes, G.
    Humensky, T. B.
    Kaaret, P.
    Kertzman, M.
    Khassen, Y.
    Kieda, D.
    Krennrich, F.
    Kumar, S.
    Lang, M. J.
    Madhavan, A. S.
    Maier, G.
    McCann, A. J.
    Meagher, K.
    Millis, J.
    Moriarty, P.
    Mukherjee, R.
    Nieto, D.
    O’Faoláin de Bhróithe, A.
    Ong, R. A.
    Otte, A. N.
    Pandel, D.
    Park, N.
    Pohl, M.
    Popkow, A.
    Prokoph, Heike
    DESY, Germany .
    Quinn, J.
    Ragan, K.
    Rajotte, J.
    Ratliff, G.
    Reyes, L. C.
    Reynolds, P. T.
    Richards, G. T.
    Roache, E.
    Rousselle, J.
    Sembroski, G. H.
    Shahinyan, K.
    Sheidaei, F.
    Smith, A. W.
    Staszak, D.
    Telezhinsky, I.
    Tsurusaki, K.
    Tucci, J. V.
    Tyler, J.
    Varlotta, A.
    Vassiliev, V. V.
    Vincent, S.
    Wakely, S. P.
    Ward, J. E.
    Weinstein, A.
    Welsing, R.
    Wilhelm, A.
    Investigating the TeV Morphology of MGRO J1908+06 with VERITAS2014In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 787, no 2, article id 166Article in journal (Refereed)
    Abstract [en]

    We report on deep observations of the extended TeV gamma-ray source MGRO J1908+06 made with the VERITAS very high energy gamma-ray observatory. Previously, the TeV emission has been attributed to the pulsar wind nebula (PWN) of theFermi-LAT pulsar PSR J1907+0602. We detect MGRO J1908+06 at a significance level of 14 standard deviations (14σ) and measure a photon index of 2.20 ± 0.10stat ± 0.20sys. The TeV emission is extended, covering the region near PSR J1907+0602 and also extending toward SNR G40.5-0.5. When fitted with a two-dimensional Gaussian, the intrinsic extension has a standard deviation of σsrc = 044 ± 002. In contrast to other TeV PWNe of similar age in which the TeV spectrum softens with distance from the pulsar, the TeV spectrum measured near the pulsar location is consistent with that measured at a position near the rim of G40.5-0.5, 033 away.

  • 231. Aliu, E.
    et al.
    Archambault, S.
    Behera, B.
    Berger, K.
    Beilicke, M.
    Benbow, W.
    Bird, R.
    Bouvier, A.
    Bugaev, V.
    Cerruti, M.
    Chen, X.
    Ciupik, L.
    Connolly, M. P.
    Cui, W.
    Dumm, J.
    Falcone, A.
    Federici, S.
    Feng, Q.
    Finley, J. P.
    Fortin, P.
    Fortson, L.
    Furniss, A.
    Galante, N.
    Gillanders, G. H.
    Griffin, S.
    Griffiths, S. T.
    Grube, J.
    Gyuk, G.
    Hanna, D.
    Holder, J.
    Hughes, G.
    Humensky, T. B.
    Kaaret, P.
    Kertzman, M.
    Khassen, Y.
    Kieda, D.
    Krennrich, F.
    Lang, M. J.
    Maier, G.
    Majumdar, P.
    McArthur, S.
    McCann, A.
    Moriarty, P.
    Mukherjee, R.
    O’Faoláin de Bhróithe, A.
    Ong, R. A.
    Otte, A. N.
    Park, N.
    Perkins, J. S.
    Pohl, M.
    Popkow, A.
    Prokoph, Heike
    DESY, Germany.
    Quinn, J.
    Ragan, K.
    Rajotte, J.
    Ratliff, G.
    Reynolds, P. T.
    Richards, G. T.
    Roache, E.
    Sembroski, G. H.
    Sheidaei, F.
    Skole, C.
    Smith, A. W.
    Staszak, D.
    Telezhinsky, I.
    Tyler, J.
    Varlotta, A.
    Vincent, S.
    Wakely, S. P.
    Weekes, T. C.
    Weinstein, A.
    Welsing, R.
    Zajczyk, A.
    Zitzer, B.
    Multiwavelength Observations of the TeV Binary LS I +61° 303 with VERITAS, Fermi-LAT, and Swift/XRT during a TeV Outburst2013In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 779, no 1, article id 88Article in journal (Refereed)
    Abstract [en]

    We present the results of a multiwavelength observational campaign on the TeV binary system LS I +61° 303 with the VERITAS telescope array (>200 GeV), Fermi-LAT (0.3-300 GeV), and Swift/XRT (2-10 keV). The data were taken from 2011 December through 2012 January and show a strong detection in all three wavebands. During this period VERITAS obtained 24.9 hr of quality selected livetime data in which LS I +61° 303 was detected at a statistical significance of 11.9σ. These TeV observations show evidence for nightly variability in the TeV regime at a post-trial significance of 3.6σ. The combination of the simultaneously obtained TeV and X-ray fluxes do not demonstrate any evidence for a correlation between emission in the two bands. For the first time since the launch of the Fermi satellite in 2008, this TeV detection allows the construction of a detailed MeV-TeV spectral energy distribution from LS I +61° 303. This spectrum shows a distinct cutoff in emission near 4 GeV, with emission seen by the VERITAS observations following a simple power-law above 200 GeV. This feature in the spectrum of LS I +61° 303, obtained from overlapping observations with Fermi-LAT and VERITAS, may indicate that there are two distinct populations of accelerated particles producing the GeV and TeV emission.

  • 232. Aliu, E.
    et al.
    Arlen, T.
    Aune, T.
    Beilicke, M.
    Benbow, W.
    Bouvier, A.
    Bradbury, S. M.
    Buckley, J. H.
    Bugaev, V.
    Byrum, K.
    Cannon, A.
    Cesarini, A.
    Ciupik, L.
    Collins-Hughes, E.
    Connolly, M. P.
    Cui, W.
    Dickherber, R.
    Duke, C.
    Errando, M.
    Falcone, A.
    Finley, J. P.
    Finnegan, G.
    Fortson, L.
    Furniss, A.
    Galante, N.
    Gall, D.
    Godambe, S.
    Griffin, S.
    Grube, J.
    Guenette, R.
    Gyuk, G.
    Hanna, D.
    Holder, J.
    Huan, H.
    Hughes, G.
    Hui, C. M.
    Humensky, T. B.
    Imran, A.
    Kaaret, P.
    Karlsson, N.
    Kertzman, M.
    Kieda, D.
    Krawczynski, H.
    Krennrich, F.
    Lang, M. J.
    LeBohec, S.
    Madhavan, A. S.
    Maier, G.
    Majumdar, P.
    McArthur, S.
    McCann, A.
    Moriarty, P.
    Mukherjee, R.
    Nuñez, P. D.
    Ong, R. A.
    Orr, M.
    Otte, A. N.
    Park, N.
    Perkins, J. S.
    Pichel, A.
    Pohl, M.
    Prokoph, Heike
    DESY, Germany .
    Quinn, J.
    Ragan, K.
    Reyes, L. C.
    Reynolds, P. T.
    Roache, E.
    Rose, H. J.
    Ruppel, J.
    Saxon, D. B.
    Schroedter, M.
    Sembroski, G. H.
    \c Sentürk, G. D.
    Skole, C.
    Staszak, D.
    Te\v sić, G.
    Theiling, M.
    Thibadeau, S.
    Tsurusaki, K.
    Tyler, J.
    Varlotta, A.
    Vassiliev, V. V.
    Vincent, S.
    Vivier, M.
    Wakely, S. P.
    Ward, J. E.
    Weekes, T. C.
    Weinstein, A.
    Weisgarber, T.
    Williams, D. A.
    Zitzer, B.
    VERITAS Observations of Day-scale Flaring of M 87 in 2010 April2012In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 746, no 2, article id 141Article in journal (Refereed)
    Abstract [en]

    VERITAS has been monitoring the very-high-energy (VHE; > 100 GeV) gamma-ray activity of the radio galaxy M 87 since 2007. During 2008, flaring activity on a timescale of a few days was observed with a peak flux of (0.70 ± 0.16) × 10–11 cm–2 s–1 at energies above 350 GeV. In 2010 April, VERITAS detected a flare from M 87 with peak flux of (2.71 ± 0.68) × 10–11 cm–2 s–1 forE > 350 GeV. The source was observed for six consecutive nights during the flare, resulting in a total of 21 hr of good-quality data. The most rapid flux variation occurred on the trailing edge of the flare with an exponential flux decay time of 0.90+0.22 –0.15 days. The shortest detected exponential rise time is three times as long, at 2.87+1.65 –0.99 days. The quality of the data sample is such that spectral analysis can be performed for three periods: rising flux, peak flux, and falling flux. The spectra obtained are consistent with power-law forms. The spectral index at the peak of the flare is equal to 2.19 ± 0.07. There is some indication that the spectrum is softer in the falling phase of the flare than the peak phase, with a confidence level corresponding to 3.6 standard deviations. We discuss the implications of these results for the acceleration and cooling rates of VHE electrons in M 87 and the constraints they provide on the physical size of the emitting region.

  • 233. Aliu, E.
    et al.
    Arlen, T.
    Aune, T.
    Beilicke, M.
    Benbow, W.
    Böttcher, M.
    Bouvier, A.
    Bradbury, S. M.
    Buckley, J. H.
    Bugaev, V.
    Cannon, A.
    Cesarini, A.
    Ciupik, L.
    Collins-Hughes, E.
    Connolly, M. P.
    Cui, W.
    Dickherber, R.
    Errando, M.
    Falcone, A.
    Finley, J. P.
    Fortson, L.
    Furniss, A.
    Galante, N.
    Gall, D.
    Gillanders, G. H.
    Godambe, S.
    Griffin, S.
    Grube, J.
    Gyuk, G.
    Hanna, D.
    Holder, J.
    Huan, H.
    Hughes, G.
    Hui, C. M.
    Humensky, T. B.
    Kaaret, P.
    Karlsson, N.
    Kertzman, M.
    Kieda, D.
    Krawczynski, H.
    Krennrich, F.
    Madhavan, A. S.
    Maier, G.
    Majumdar, P.
    McArthur, S.
    McCann, A.
    Moriarty, P.
    Mukherjee, R.
    Ong, R. A.
    Orr, M.
    Otte, A. N.
    Park, N.
    Perkins, J. S.
    Pichel, A.
    Pohl, M.
    Prokoph, Heike
    DESY, Germany.
    Quinn, J.
    Ragan, K.
    Reyes, L. C.
    Reynolds, P. T.
    Roache, E.
    Rose, H. J.
    Ruppel, J.
    Saxon, D. B.
    Schroedter, M.
    Sembroski, G. H.
    Skole, C.
    Smith, A. W.
    Staszak, D.
    Te\v sić, G.
    Theiling, M.
    Thibadeau, S.
    Tsurusaki, K.
    Tyler, J.
    Varlotta, A.
    Vincent, S.
    Vivier, M.
    Wakely, S. P.
    Ward, J. E.
    Weinstein, A.
    Weisgarber, T.
    Williams, D. A.
    VERITAS Observations of the Unusual Extragalactic Transient Swift J164449.3+5734512011In: Astrophysical Journal Letters, ISSN 2041-8205, E-ISSN 2041-8213, Vol. 738, no 2, article id L30Article in journal (Refereed)
    Abstract [en]

    We report on very high energy (>100 GeV) gamma-ray observations of Swift J164449.3+573451, an unusual transient object first detected by the Swift Observatory and later detected by multiple radio, optical, and X-ray observatories. A total exposure of 28 hr was obtained on Swift J164449.3+573451 with the Very Energetic Radiation Imaging Telescope Array System (VERITAS) during 2011 March 28-April 15. We do not detect the source and place a differential upper limit on the emission at 500 GeV during these observations of 1.4 × 10–12 erg cm–2 s–1 (99% confidence level). We also present time-resolved upper limits and use a flux limit averaged over the X-ray flaring period to constrain various emission scenarios that can accommodate both the radio-through-X-ray emission detected from the source and the lack of detection by VERITAS.

  • 234. Aliu, E.
    et al.
    Aune, T.
    Barnacka, A.
    Beilicke, M.
    Benbow, W.
    Berger, K.
    Biteau, J.
    Buckley, J. H.
    Bugaev, V.
    Byrum, K.
    Cardenzana, J. V.
    Cerruti, M.
    Chen, X.
    Ciupik, L.
    Connaughton, V.
    Cui, W.
    Dickinson, H. J.
    Eisch, J. D.
    Errando, M.
    Falcone, A.
    Federici, S.
    Feng, Q.
    Finley, J. P.
    Fleischhack, H.
    Fortin, P.
    Fortson, L.
    Furniss, A.
    Galante, N.
    Gillanders, G. H.
    Griffin, S.
    Griffiths, S. T.
    Grube, J.
    Gyuk, G.
    Håkansson, N.
    Hanna, D.
    Holder, J.
    Hughes, G.
    Humensky, T. B.
    Johnson, C. A.
    Kaaret, P.
    Kar, P.
    Kertzman, M.
    Khassen, Y.
    Kieda, D.
    Krawczynski, H.
    Krennrich, F.
    Lang, M. J.
    Madhavan, A. S.
    Maier, G.
    McArthur, S.
    McCann, A.
    Meagher, K.
    Millis, J.
    Moriarty, P.
    Mukherjee, R.
    Nieto, D.
    O’Faoláin de Bhróithe, A.
    Ong, R. A.
    Otte, A. N.
    Park, N.
    Pohl, M.
    Popkow, A.
    Prokoph, Heike
    DESY, Germany .
    Pueschel, E.
    Quinn, J.
    Ragan, K.
    Rajotte, J.
    Reyes, L. C.
    Reynolds, P. T.
    Richards, G. T.
    Roache, E.
    Sembroski, G. H.
    Shahinyan, K.
    Smith, A. W.
    Staszak, D.
    Telezhinsky, I.
    Tucci, J. V.
    Tyler, J.
    Varlotta, A.
    Vassiliev, V. V.
    Vincent, S.
    Wakely, S. P.
    Weiner, O. M.
    Weinstein, A.
    Welsing, R.
    Wilhelm, A.
    Williams, D. A.
    Zitzer, B.
    McEnery, J. E.
    Perkins, J. S.
    Veres, P.
    Zhu, S.
    Constraints on Very High Energy Emission from GRB 130427A2014In: Astrophysical Journal Letters, ISSN 2041-8205, E-ISSN 2041-8213, Vol. 795, no 1, article id L3Article in journal (Refereed)
    Abstract [en]

    Prompt emission from the very fluent and nearby (z = 0.34) gamma-ray burst GRB 130427A was detected by several orbiting telescopes and by ground-based, wide-field-of-view optical transient monitors. Apart from the intensity and proximity of this GRB, it is exceptional due to the extremely long-lived high-energy (100 MeV to 100 GeV) gamma-ray emission, which was detected by the Large Area Telescope on the Fermi Gamma-Ray Space Telescope for ~70 ks after the initial burst. The persistent, hard-spectrum, high-energy emission suggests that the highest-energy gamma rays may have been produced via synchrotron self-Compton processes though there is also evidence that the high-energy emission may instead be an extension of the synchrotron spectrum. VERITAS, a ground-based imaging atmospheric Cherenkov telescope array, began follow-up observations of GRB 130427A ~71 ks (~20 hr) after the onset of the burst. The GRB was not detected with VERITAS; however, the high elevation of the observations, coupled with the low redshift of the GRB, make VERITAS a very sensitive probe of the emission from GRB 130427A for E > 100 GeV. The non-detection and consequent upper limit derived place constraints on the synchrotron self-Compton model of high-energy gamma-ray emission from this burst.

  • 235. Aliu, E.
    et al.
    Aune, T.
    Behera, B.
    Beilicke, M.
    Benbow, W.
    Berger, K.
    Bird, R.
    Buckley, J. H.
    Bugaev, V.
    Cardenzana, J. V.
    Cerruti, M.
    Chen, X.
    Ciupik, L.
    Connolly, M. P.
    Cui, W.
    Duke, C.
    Dumm, J.
    Errando, M.
    Falcone, A.
    Federici, S.
    Feng, Q.
    Finley, J. P.
    Fortin, P.
    Fortson, L.
    Furniss, A.
    Galante, N.
    Gillanders, G. H.
    Griffin, S.
    Griffiths, S. T.
    Grube, J.
    Gyuk, G.
    Hanna, D.
    Holder, J.
    Hughes, G.
    Humensky, T. B.
    Kaaret, P.
    Kargaltsev, O.
    Kertzman, M.
    Khassen, Y.
    Kieda, D.
    Krawczynski, H.
    Lang, M. J.
    Madhavan, A. S.
    Maier, G.
    Majumdar, P.
    McCann, A.
    Moriarty, P.
    Mukherjee, R.
    Nieto, D.
    O’Faoláin de Bhróithe, A.
    Ong, R. A.
    Otte, A. N.
    Pandel, D.
    Perkins, J. S.
    Pohl, M.
    Popkow, A.
    Prokoph, Heike
    DESY, Germany .
    Quinn, J.
    Ragan, K.
    Rajotte, J.
    Reyes, L. C.
    Reynolds, P. T.
    Richards, G. T.
    Roache, E.
    Sembroski, G. H.
    Skole, C.
    Staszak, D.
    Telezhinsky, I.
    Theiling, M.
    Tucci, J. V.
    Tyler, J.
    Varlotta, A.
    Vincent, S.
    Wakely, S. P.
    Weekes, T. C.
    Weinstein, A.
    Welsing, R.
    Williams, D. A.
    Zitzer, B.
    Observations of the Unidentified Gamma-Ray Source TeV J2032+4130 by VERITAS2014In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 783Article in journal (Refereed)
    Abstract [en]

    TeV J2032+4130 was the first unidentified source discovered at very high energies (VHEs; E > 100 GeV), with no obvious counterpart in any other wavelength. It is also the first extended source to be observed in VHE gamma rays. Following its discovery, intensive observational campaigns have been carried out in all wavelengths in order to understand the nature of the object, which have met with limited success. We report here on a deep observation of TeV J2032+4130   based on 48.2 hr of data taken from 2009 to 2012 by the Very Energetic Radiation Imaging Telescope Array System experiment. The source is detected at 8.7 standard deviations (σ) and is found to be extended and asymmetric with a width of 9.'5 ± 1.'2 along the major axis and 4.'0 ± 0.'5 along the minor axis. The spectrum is well described by a differential power law with an index of 2.10 ± 0.14stat ± 0.21sys and a normalization of (9.5 ± 1.6stat ± 2.2sys× 10–13 TeV–1 cm–2 s–1 at 1 TeV. We interpret these results in the context of multiwavelength scenarios which particularly favor the pulsar wind nebula interpretation.

  • 236. Aliu, E.
    et al.
    Aune, T.
    Beilicke, M.
    Benbow, W.
    Böttcher, M.
    Bouvier, A.
    Bradbury, S. M.
    Buckley, J. H.
    Bugaev, V.
    Cannon, A.
    Cesarini, A.
    Ciupik, L.
    Connolly, M. P.
    Cui, W.
    Decerprit, G.
    Dickherber, R.
    Duke, C.
    Errando, M.
    Falcone, A.
    Feng, Q.
    Finnegan, G.
    Fortson, L.
    Furniss, A.
    Galante, N.
    Gall, D.
    Gillanders, G. H.
    Godambe, S.
    Griffin, S.
    Grube, J.
    Gyuk, G.
    Hanna, D.
    Hivick, B.
    Holder, J.
    Huan, H.
    Hughes, G.
    Hui, C. M.
    Humensky, T. B.
    Kaaret, P.
    Karlsson, N.
    Kertzman, M.
    Kieda, D.
    Krawczynski, H.
    Krennrich, F.
    Maier, G.
    Majumdar, P.
    McArthur, S.
    McCann, A.
    Moriarty, P.
    Mukherjee, R.
    Nelson, T.
    Ong, R. A.
    Orr, M.
    Otte, A. N.
    Park, N.
    Perkins, J. S.
    Pichel, A.
    Pohl, M.
    Prokoph, Heike
    DESY, Germany.
    Quinn, J.
    Ragan, K.
    Reyes, L. C.
    Reynolds, P. T.
    Roache, E.
    Rose, H. J.
    Ruppel, J.
    Saxon, D. B.
    Sembroski, G. H.
    Skole, C.
    Smith, A. W.
    Staszak, D.
    Tesić, G.
    Theiling, M.
    Thibadeau, S.
    Tsurusaki, K.
    Tyler, J.
    Varlotta, A.
    Vassiliev, V. V.
    Wakely, S. P.
    Weekes, T. C.
    Weinstein, A.
    Williams, D. A.
    Zitzer, B.
    Collaboration, V E R I T A S
    Ciprini, S.
    Fumagalli, M.
    Kaplan, K.
    Paneque, D.
    Prochaska, J. X.
    Multiwavelength Observations of the Previously Unidentified Blazar RX J0648.7+15162011In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 742, no 2, article id 127Article in journal (Refereed)
    Abstract [en]

    We report on the VERITAS discovery of very high energy (VHE) gamma-ray emission above 200 GeV from the high-frequency-peaked BL Lac (HBL) object RX J0648.7+1516 (GB J0648+1516), associated with 1FGL J0648.8+1516. The photon spectrum above 200 GeV is fitted by a power law dN/dE = F 0(E/E 0)–Γ with a photon index Γ of 4.4 ± 0.8stat ± 0.3syst and a flux normalization F 0 of (2.3 ± 0.5stat ± 1.2sys× 10–11 TeV–1 cm–2 s–1 with E 0 = 300 GeV. No VHE variability is detected during VERITAS observations of RX J0648.7+1516 between 2010 March 4 and April 15. Following the VHE discovery, the optical identification and spectroscopic redshift were obtained using the Shane 3 m Telescope at the Lick Observatory, showing the unidentified object to be a BL Lac type with a redshift of z = 0.179. Broadband multiwavelength observations contemporaneous with the VERITAS exposure period can be used to subclassify the blazar as an HBL object, including data from the MDM observatory, Swift-UVOT, and X-Ray Telescope, and continuous monitoring at photon energies above 1 GeV from the FermiLarge Area Telescope (LAT). We find that in the absence of undetected, high-energy rapid variability, the one-zone synchrotron self-Compton (SSC) model overproduces the high-energy gamma-ray emission measured by the Fermi-LAT over 2.3 years. The spectral energy distribution can be parameterized satisfactorily with an external-Compton or lepto-hadronic model, which have two and six additional free parameters, respectively, compared to the one-zone SSC model.

  • 237. AMANDA Collaboration, -
    et al.
    Pohl, Arvid
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Flux limits on ultra high energy neutrinos with AMANDA-B102005In: Astroparticle physics, ISSN 0927-6505, E-ISSN 1873-2852, Vol. 22, no 5-6, p. 339-353Article in journal (Refereed)
    Abstract [en]

    Data taken during 1997 with the AMANDA-B10 detector are searched for a diffuse flux of neutrinos of all flavors with energies above 10(16) eV. At these energies the Earth is opaque to neutrinos, and thus neutrino induced events are concentrated at the horizon. The background are large muon bundles from down-going atmospheric air shower events. No excess events above the background expectation are observed and a neutrino flux following E-2, with an equal mix of all flavors, is limited to E(2)Phi(10(15) eV < E < 3 x 10(18) eV) less than or equal to 0.99 x 10(-6) GeV cm(-2) s(-1) sr(-1) at 90% confidence level. This is the most restrictive experimental bound placed by any neutrino detector at these energies. Bounds to specific extraterrestrial neutrino flux predictions are also presented. 

  • 238. AMANDA Collaboration, -
    et al.
    Pohl, Arvid
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Limits to the muon flux from neutralino annihilations at the Center of the Earth with AMANDA2006In: Astroparticle physics, ISSN 0927-6505, E-ISSN 1873-2852, Vol. 26, no 2, p. 129-139Article in journal (Refereed)
    Abstract [en]

    A search has been performed for nearly vertically upgoing neutrino-induced muons with the Antarctic Muon And Neutrino DetectorArray (AMANDA), using data taken over the three year period 1997–99. No excess above the expected atmospheric neutrino backgroundhas been found. Upper limits at 90% confidence level have been set on the annihilation rate of neutralinos at the center ofthe Earth, as well as on the muon flux at AMANDA induced by neutrinos created by the annihilation products.

  • 239. AMANDA Collaboration, -
    et al.
    Pohl, Arvid
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Limits to the muon flux from neutralino annihilations in the Sun with the AMANDA detector2006In: Astroparticle physics, ISSN 0927-6505, E-ISSN 1873-2852, Vol. 24, no 6, p. 459-466Article in journal (Refereed)
    Abstract [en]

    A search for an excess of muon-neutrinos from neutralino annihilations in the Sun has been performed with the AMANDA-II neutrino detector using data collected in 143.7 days of live-time in 2001. No excess over the expected atmospheric neutrino background has been observed. An upper limit at 90% confidence level has been obtained on the annihilation rate of captured neutralinos in the Sun, as well as the corresponding muon flux limit at the Earth, both as functions of the neutralino mass in the range 100-5000 GeV. 

  • 240. AMANDA Collaboration, -
    et al.
    Pohl, Arvid
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Search for extraterrestrial point sources of high energy neutrinos with AMANDA-II using data collected in 2000-20022005In: Physical Review D. Particles and fields, ISSN 0556-2821, E-ISSN 1089-4918, Vol. 71, no 7, p. 077102-Article in journal (Refereed)
    Abstract [en]

    The results of a search for point sources of high energy neutrinos in the northern hemisphere using data collected by AMANDA-II in the years 2000, 2001, and 2002 are presented. In particular, a comparison with the single-year result previously published shows that the sensitivity was improved by a factor of 2.2. The muon neutrino flux upper limits on selected candidate sources, corresponding to an E-nu(-2) neutrino energy spectrum, are included. Sky grids were used to search for possible excesses above the background of cosmic ray induced atmospheric neutrinos. This search reveals no statistically significant excess for the three years considered. 

  • 241. AMANDA Collaboration, -
    et al.
    Pohl, Arvid
    University of Kalmar, School of Pure and Applied Natural Sciences.
    The ICECUBE prototype string in AMANDA2006In: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, ISSN 0168-9002, E-ISSN 1872-9576, Vol. 556, no 1, p. 169-181Article in journal (Refereed)
    Abstract [en]

    The Antarctic Muon And Neutrino Detector Array (AMANDA) is a high-energy neutrino telescope. It is a lattice of optical modules (OM) installed in the clear ice below the South Pole Station. Each OM contains a photomultiplier tube (PMT) that detects photons of Cherenkov light generated in the ice by muons and electrons. ICECUBE is a cubic-kilometer-sized expansion of AMANDA currently being built at the South Pole. In ICECUBE the PMT signals are digitized already in the optical modules and transmitted to the surface. A prototype string of 41 OMs equipped with this new all-digital technology was deployed in the AMANDA array in the year 2000. In this paper we describe the technology and demonstrate that this string serves as a proof of concept for the ICECUBE array. Our investigations show that the OM timing accuracy is 5 ns. Atmospheric muons are detected in excellent agreement with expectations with respect to both angular distribution and absolute rate. 

  • 242. Amann, F.
    et al.
    Black, K.
    Bolton, R. D.
    Carius, Staffan
    Cooper, M. D.
    Foreman, W.
    Hansen, C.
    Harrison, R.
    Hart, G.
    Hart, V.
    Hoffman, C. M.
    Hoffman, N.
    Hunter, T.
    Hogan, G. E.
    June, N.
    Kercher, D.
    Little, J.
    Kozlowski, T.
    Mischke, R. E.
    Naivar, F. J.
    Novak, J.
    Oothoudt, M. A.
    Pillai, C.
    Schilling, S.
    Smith, W.
    Stanislaus, S.
    Sturrock, J.
    Szymanski, J.
    Van Dyke, J.
    Werbeck, R. D.
    Whitehouse, D.
    Wilkinson, C.
    Crocker, J.
    Wright, S. C.
    Cooper, P. S.
    Dzemidzic, M.
    Flick, J.
    Hungerford, E. V. , I I I
    Johnston, K.
    Lan, K.
    Mayes, B. W. , I I
    Phelps, R.
    Pinsky, L.
    von Witsch, W.
    Hallin, A.
    Hughes, E. B.
    Jui, C.
    Otis, J. N.
    Ritter, M. W.
    Gagliardi, C.
    Kim, G.
    Liu, F.
    Tribble, R. E.
    Van Ausdeln, L.
    Barlow, D.
    Kessler, R.
    Nefkens, B. M. K.
    Price, J.
    Tippens, B.
    Fisk, R. J.
    Koetke, D. D.
    Manweiler, R.
    Marshall, R.
    Stephens, W.
    Ziock, K. O. H.
    Piilonen, L. E.
    Kunselman, A. R.
    Hahn, K.
    Markey, J. K.
    Phua, K. K.
    Yamaguchi, Y.
    A search for murarregamma at the level of 10-131991In: Proceedings of the 25th International Conference on High Energy Physics, 1991, p. 1070-1071Conference paper (Refereed)
    Abstract [en]

    The MEGA experiment, which is a search for the decay murarregamma with a branching ratio sensitivity of about 10-13, employs highly modular, fast detectors, state-of-the-art electronics, and a staged trigger with on-line filters. The detectors are contained in a 1.5-T solenoidal field produced by a superconducting magnet. Positrons are confined to the central region and are measured by a set of thin MWPCs. Photons are measured by one of four layers of pair spectrometers in the outer region. Most aspects of the design have been validated in engineering runs; data taking will begin in 1990 with much of the electron arm and one pair spectrometer layer installed.

  • 243. Ambrosio, M
    et al.
    Antolini, R
    Assiro, R
    Auriemma, G
    Bakari, D
    Baldini, A
    Barbarino, G C
    Barbarito, E
    Barish, B C
    Battistoni, G
    Becherini, Yvonne
    Università di Bologna.
    Bellotti, R
    Bemporad, C
    Bernardini, P
    Bilokon, H
    Bisi, V
    Bloise, C
    Bottazzi, E
    Bower, C
    Brigida, M
    Bussino, S
    Cafagna, F
    Calicchio, M
    Campana, D
    Candela, A
    Carboni, M
    Cecchini, S
    Cei, F
    Ceres, A
    Chiarella, V
    Choudhary, B C
    Coutu, S
    Cozzi, M
    Creti, P
    De Cataldo, G
    Degli Esposti, L
    Dekhissi, H
    De Marzo, C
    De Mitri, I
    Derkaoui, J
    De Vincenzi, M
    Di Credico, A
    Di Ferdinando, D
    Diotallevi, R
    Erriquez, O
    Favuzzi, C
    Forti, C
    Fusco, P
    Gebhard, M
    Giacomelli, G
    Giacomelli, R
    Giannini, G
    Giglietto, N
    Giorgini, M
    Giuliani, R
    Goretti, M
    Grassi, M
    Grau, H
    Gray, L
    Grillo, A
    Guarino, F
    Gustavino, C
    Habig, A
    Hanson, J
    Hanson, K
    Hawthorne, A
    Heinz, R
    Hong, J T
    Iarocci, E
    Katsavounidis, E
    Katsavounidis, I
    Kearns, E
    Kim, H
    Kyriazopoulou, S
    Lamanna, E
    Lane, C
    Leone, A
    Levin, D S
    Lipari, P
    Liu, G
    Liu, R
    Longley, N P
    Longo, M J
    Loparco, F
    Maaroufi, F
    Mancarella, G
    Mandrioli, G
    Manzoor, S
    Marrelli, V
    Margiotta, A
    Marini, A
    Martello, D
    Marzari-Chiesa, A
    Mazziotta, M N
    Michael, D G
    Mikheyev, S
    Miller, L
    Monacelli, P
    Mongelli, M
    Montaruli, T
    Monteno, M
    Mossbarger, L
    Mufson, S
    Musser, J
    Nicolo, D
    Nolty, R
    Okada, C
    Orsini, M
    Orth, C
    Osteria, G
    Ouchrif, M
    Palamara, O
    Parlati, S
    Patera, V
    Patrizii, L
    Pazzi, R
    Peck, C W
    Pellizzoni, G
    Perchiazzi, M
    Perrone, L
    Petrakis, J
    Petrera, S
    Pignatano, N
    Pinto, C
    Pistilli, P
    Popa, V
    Raino, A
    Reynoldson, J
    Ronga, F
    Rrhioua, A
    Sacchetti, A
    Saggese, P
    Satriano, C
    Satta, L
    Scapparone, E
    Scholberg, K
    Sciubba, A
    Serra, P
    Sioli, M
    Sirri, G
    Sitta, M
    Sondergaard, S
    Spinelli, P
    Spinetti, M
    Spurio, M
    Stalio, S
    Steinberg, R
    Stone, J L
    Sulak, L R
    Surdo, A
    Tarle, G
    Togo, V
    Vakili, M
    Valieri, C
    Walter, C W
    Webb, R
    Zaccheo, N
    The MACRO detector at Gran Sasso2002In: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, ISSN 0168-9002, E-ISSN 1872-9576, Vol. 486, no 3, p. 663-707Article in journal (Refereed)
    Abstract [en]

    MACRO was an experiment that ran in the Laboratori Nazionali del Gran Sasso from 1988 to 2000. Its principal goal was to observe magnetic monopoles or set significantly lower experimental flux limits than had been previously available in the velocity range from about beta = 10(-4) to unity. In addition it made a variety of other observations. Examples are: setting flux limits on other so far unobserved particles such as nuclearites and lightly ionizing particles, searching for WIMP annihilations in the Earth and the Sun and for neutrino bursts from stellar collapses in or near our Galaxy, and making measurements relevant to high energy muon and neutrino astronomy and of the flux of up-going muons as a function of nadir angle showing evidence for neutrino oscillations. The apparatus consisted of three principal types of detectors: liquid scintillator counters, limited streamer tubes, and nuclear track etch detectors. In addition, over part of its area it contained a transition radiation detector. The general design philosophy emphasized redundancy and complementarity. This paper describes the technical aspects of the complete MACRO detector, its operational performance, and the techniques used to calibrate it and verify its proper operation. It supplements a previously published paper which described the first portion of the detector that was built and operated. (C) 2002 Elsevier Science B.V. All rights reserved.

  • 244. Ambrosio, M
    et al.
    Antolini, R
    Auriemma, G
    Bakari, D
    Baldini, A
    Barbarino, G C
    Barish, B C
    Battistoni, G
    Becherini, Yvonne
    Università di Bologna .
    Bellotti, R
    Bemporad, C
    Bernardini, P
    Bilokon, H
    Bisi, V
    Bloise, C
    Bower, C
    Brigida, M
    Bussino, S
    Cafagna, F
    Calicchio, M
    Campana, D
    Carboni, M
    Caruso, R
    Cecchini, S
    Cei, F
    Chiarella, V
    Choudhary, B C
    Coutu, S
    De Cataldo, G
    Dekhissi, H
    De Marzo, C
    De Mitri, I
    Derkaoui, J
    De Vincenzi, M
    Di Credico, A
    Erriquez, O
    Favuzzi, C
    Forti, C
    Fusco, P
    Giacomelli, G
    Giannini, G
    Giglietto, N
    Giorgini, M
    Grassi, M
    Gray, L
    Grillo, A
    Guarino, F
    Gustavino, C
    Habig, A
    Hanson, K
    Heinz, R
    Iarocci, E
    Katsavounidis, E
    Katsavounidis, I
    Kearns, E
    Kim, H
    Kyriazopoulou, S
    Lamanna, E
    Lane, C
    Levin, D S
    Lipari, P
    Longley, N P
    Longo, M J
    Loparco, F
    Maaroufi, F
    Mancarella, G
    Mandrioli, G
    Margiotta, A
    Marini, A
    Martello, D
    Marzari-Chiesa, A
    Mazziotta, M N
    Michael, D G
    Mikheyev, S
    Miller, L
    Monacelli, P
    Montaruli, T
    Monteno, M
    Mufson, S
    Musser, J
    Nicolo, D
    Nolty, R
    Orth, C
    Osteria, G
    Palamara, O
    Patera, V
    Patrizii, L
    Pazzi, R
    Peck, C W
    Perrone, L
    Petrera, S
    Pistilli, P
    Popa, V
    Raino, A
    Reynoldson, J
    Ronga, F
    Rrhioua, A
    Satriano, C
    Scapparone, E
    Scholberg, K
    Sciubba, A
    Serra, P
    Sioli, M
    Sirri, G
    Sitta, M
    Spinelli, P
    Spinetti, M
    Spurio, M
    Steinberg, R
    Stone, J L
    Sulak, L R
    Surdo, A
    Tarle, G
    Togo, V
    Vakili, M
    Walter, C W
    Webb, R
    Matter effects in upward-going muons and sterile neutrino oscillations2001In: Physics Letters B, ISSN 0370-2693, E-ISSN 1873-2445, Vol. 517, no 1-2, p. 59-66Article in journal (Refereed)
    Abstract [en]

    The angular distribution of upward-going muons produced by atmospheric neutrinos in the rock below the MACRO detector shows anomalies in good agreement with two flavor nu (mu) --> nu (tau) oscillations with maximum mixing and Deltam(2) around 0.0024 eV(2). Exploiting the dependence of magnitude of the matter effect on oscillation channel, and using a set of 809 upward-going muons observed in MACRO, we show that the two flavor nu (mu) --> nu (s) oscillation is disfavored with 99% C.L. with respect to nu (mu) --> nu (tau). (C) 2001 Elsevier Science B.V. All rights reserved.

  • 245. Ambrosio, M
    et al.
    Antolini, R
    Auriemma, G
    Bakari, D
    Baldini, A
    Barbarino, G C
    Barish, B C
    Battistoni, G
    Becherini, Yvonne
    Università di Bologna .
    Bellotti, R
    Bemporad, C
    Bernardini, P
    Bilokon, H
    Bloise, C
    Bower, C
    Brigida, M
    Bussino, S
    Cafagna, F
    Calicchio, M
    Campana, D
    Candela, A
    Carboni, M
    Caruso, R
    Cassese, F
    Cecchini, S
    Cei, F
    Chiarella, V
    Choudhary, B C
    Coutu, S
    Cozzi, M
    De Cataldo, G
    De Deo, M
    Dekhissi, H
    De Marzo, C
    De Mitri, I
    Derkaoui, J
    De Vincenzi, M
    Di Credico, A
    Dincecco, M
    Erriquez, O
    Favuzzi, C
    Forti, C
    Fusco, P
    Giacomelli, G
    Giannini, G
    Giglietto, N
    Giorgini, M
    Grassi, M
    Gray, L
    Grillo, A
    Guarino, F
    Gustavino, C
    Habig, A
    Hanson, K
    Heinz, R
    Iarocci, E
    Katsavounidis, E
    Katsavounidis, I
    Kearns, E
    Kim, H
    Kyriazopoulou, S
    Lamanna, E
    Lane, C P
    Levin, D S
    Lindozzi, M
    Lipari, P
    Longley, N P
    Longo, M J
    Loparco, F
    Marroufi, F
    Mancarella, G
    Mandrioli, G
    Margiotta, A
    Marini, A
    Martello, D
    Marzari-Chiesa, A
    Mazziotta, M N
    Michael, D G
    Monacelli, P
    Montaruli, T
    Monteno, M
    Mufson, S
    Musser, J
    Nicolo, D
    Nolty, R
    Orth, C
    Osteria, G
    Palamara, O
    Patera, V
    Patrizii, L
    Pazzi, R
    Peck, C W
    Perrone, L
    Petrera, S
    Pistilli, P
    Popa, V
    Raino, A
    Reynoldson, J
    Ronga, F
    Rrhioua, A
    Satriano, C
    Scapparone, E
    Scholberg, K
    Sciubba, A
    Serra, P
    Sioli, M
    Sirri, G
    Sitta, M
    Spinelli, P
    Spinetti, M
    Spurio, M
    Steinberg, R
    Stone, J L
    Sulak, L R
    Surdo, A
    Tarle, G
    Tatananni, E
    Togo, V
    Vakili, M
    Walter, C W
    Webb, R
    Muon energy estimate through multiple scattering with the MACRO detector2002In: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, ISSN 0168-9002, E-ISSN 1872-9576, Vol. 492, no 3, p. 376-386Article in journal (Refereed)
    Abstract [en]

    Muon energy measurement represents an important issue for any experiment addressing neutrino-induced up-going muon studies. Since the neutrino oscillation probability depends on the neutrino energy, a measurement of the muon energy adds an important piece of information concerning the neutrino system. We show in this paper how the MACRO limited streamer tube system can be operated in drift mode by using the TDCs included in the QTPs, an electronics designed for magnetic monopole search. An improvement of the space resolution is obtained, through an analysis of the multiple scattering of muon tracks as they pass through our detector. This information can be used further to obtain an estimate of the energy of muons crossing the detector. Here we present the results of two dedicated tests, performed at CERN PS-T9 and SPS-X7 beam lines, to provide a full check of the electronics and to exploit the feasibility of such a multiple scattering analysis. We show that by using a neural network approach, we are able to reconstruct the muon energy for E-mu < 40 GeV. The test beam data provide an absolute energy calibration, which allows us to apply this method to MACRO data. (C) 2002 Elsevier Science B.V. All rights reserved.

  • 246.
    Ambrosio, M
    et al.
    Università di Napoli, Italy ; INFN, Italy.
    Antolini, R
    Laboratori Nazionali del Gran Sasso dell’INFN, Italy.
    Auriemma, G
    Università di Roma “La Sapienza”, Italy ; INFN, Italy.
    Bakari, D
    Università di Bologna, Italy ; INFN, Italy ; University Mohamed I, Morocco.
    Baldini, A
    Università di Pisa, Italy ; INFN, Italy.
    Barbarino, G C
    Università di Napoli, Italy ; INFN, Italy.
    Barish, B C
    California Institute of Technology, USA.
    Battistoni, G
    INFN, Italy.
    Becherini, Yvonne
    Boston University, USA.
    Bellotti, R
    Università di Bari, Italy ; INFN. Italy.
    Bemporad, C
    Università di Pisa, Italy ; INFN, Italy.
    Bernardini, P
    Università di Lecce, Italy ; INFN, Italy.
    Bilokon, H
    Bloise, C
    Bower, C
    Brigida, M
    Bussino, S
    Cafagna, F
    Calicchio, M
    Campana, D
    Carboni, M
    Caruso, R
    Cecchini, S
    Cei, F
    Chiarella, V
    Chiarusi, T
    Choudhary, B C
    Coutu, S
    Cozzi, M
    De Cataldo, G
    Dekhissi, H
    De Marzo, C
    De Mitri, I
    Derkaoui, J
    De Vincenzi, M
    Di Credico, A
    Erriquez, O
    Favuzzi, C
    Forti, C
    Fusco, P
    Giacomelli, G
    Giannini, G
    Giglietto, N
    Giorgini, M
    Grassi, M
    Grillo, A
    Guarino, F
    Gustavino, C
    Habig, A
    Hanson, K
    Heinz, R
    Iarocci, E
    Katsavounidis, E
    Katsavounidis, I
    Kearns, E
    Kim, H
    Kyriazopoulou, S
    Kumar, A
    Lamanna, E
    Lane, C
    Levin, D S
    Lipari, P
    Longley, N P
    Longo, M J
    Loparco, F
    Maaroufi, F
    Mancarella, G
    Mandrioli, G
    Manzoor, S
    Margiotta, A
    Marini, A
    Martello, D
    Marzari-Chiesa, A
    Matteuzzi, D
    Mazziotta, M N
    Michael, D G
    Monacelli, P
    Montaruli, T
    Monteno, M
    Mufson, S
    Musser, J
    Nicolo, D
    Nolty, R
    Orth, C
    Osteria, G
    Palamara, O
    Patera, V
    Patrizii, L
    Pazzi, R
    Peck, C W
    Perrone, L
    Petrera, S
    Pistilli, P
    Popa, V
    Raino, A
    Reynoldson, J
    Ronga, F
    Rrhioua, A
    Satriano, C
    Scapparone, E
    Scholberg, K
    Sciubba, A
    Serra, P
    Sioli, M
    Sirri, G
    Sitta, M
    Spinelli, P
    Spinetti, M
    Spurio, M
    Steinberg, R
    Stone, J L
    Sulak, L R
    Surdo, A
    Tarle, G
    Togo, V
    Vakili, M
    Walter, C W
    Webb, R
    Final results of magnetic monopole searches with the MACRO experiment2002In: European Physical Journal C, ISSN 1434-6044, E-ISSN 1434-6052, Vol. 25, no 4, p. 511-522Article in journal (Refereed)
    Abstract [en]

    We present the final results obtained by the MACRO experiment in the search for GUT magnetic monopoles in the penetrating cosmic radiation, for the range 4 x 10(-5) < 3 < 1. Several searches with all the MACRO sub-detectors (i.e. scintillation counters, limited streamer tubes and nuclear track detectors) were performed, both in stand alone and combined ways. No candidates were detected and a 90% Confidence Level (C.L.) upper limit to the local magnetic monopole flux was set at the level of 1.4 x 10(-16) cm(-2) s(-1) sr(-1). This result is the first experimental limit obtained in direct searches which is well below the Parker bound in the whole 3 range in which GUT magnetic monopoles are,expected.

  • 247. Ambrosio, M
    et al.
    Antolini, R
    Auriemma, G
    Bakari, D
    Baldini, A
    Barbarino, G C
    Barish, B C
    Battistoni, G
    Becherini, Yvonne
    Università di Bologna, Italy ; INFN, Italy.
    Bellotti, R
    Bemporad, C
    Bernardini, P
    Bilokon, H
    Bloise, C
    Bower, C
    Brigida, M
    Bussino, S
    Cafagna, F
    Calicchio, M
    Campana, D
    Carboni, M
    Caruso, R
    Cecchini, S
    Cei, F
    Chiarella, V
    Choudhary, B C
    Coutu, S
    Cozzi, M
    De Cataldo, G
    Dekhissi, H
    De Marzo, C
    De Mitri, I
    Derkaoui, J
    De Vincenzi, M
    Di Credico, A
    Erriquez, O
    Favuzzi, C
    Forti, C
    Fusco, P
    Giacomelli, G
    Giannini, G
    Giglietto, N
    Giorgini, M
    Grassi, M
    Grillo, A
    Guarino, F
    Gustavino, C
    Habig, A
    Hanson, K
    Heinz, R
    Iarocci, E
    Katsavounidis, E
    Katsavounidis, I
    Kearns, E
    Kim, H
    Kyriazopoulou, S
    Lamanna, E
    Lane, C
    Levin, D S
    Lipari, P
    Longley, N P
    Longo, M J
    Loparco, F
    Maaroufi, F
    Mancarella, G
    Mandrioli, G
    Manzoor, S
    Margiotta, A
    Marini, A
    Martello, D
    Marzari-Chiesa, A
    Mazziotta, M N
    Michael, D G
    Monacelli, P
    Montaruli, T
    Monteno, M
    Mufson, S
    Musser, J
    Nicolo, D
    Nolty, R
    Orth, C
    Osteria, G
    Palamara, O
    Patera, V
    Patrizii, L
    Pazzi, R
    Peck, C W
    Perrone, L
    Petrera, S
    Pistilli, P
    Popa, V
    Raino, A
    Reynoldson, J
    Ronga, F
    Rrhioua, A
    Satriano, C
    Scapparone, E
    Scholberg, K
    Sciubba, A
    Serra, P
    Sioli, M
    Sirri, G
    Sitta, M
    Spinelli, P
    Spinetti, M
    Spurio, M
    Steinberg, R
    Stone, J L
    Sulak, L R
    Surdo, A
    Tarle, G
    Togo, V
    Vakili, M
    Walter, C W
    Webb, R
    Search for nucleon decays induced by GUT magnetic monopoles with the MACRO experiment2002In: European Physical Journal C, ISSN 1434-6044, E-ISSN 1434-6052, Vol. 26, no 2, p. 163-172Article in journal (Refereed)
    Abstract [en]

    The interaction of a Grand Unification Magnetic Monopole with a nucleon can lead to a barion-number violating process in which the nucleon decays into a lepton and one or more mesons (catalysis of nucleon decay). In this paper we report an experimental study of the effects of a catalysis process in the MACRO detector. Using a dedicated analysis we obtain new magnetic monopole (MM) flux upper limits at the level of similar to 3 (.) 10(-16) cm(-2) s(-1) sr(-1) for 1.1(.) 10(-4) less than or equal to \beta\ less than or equal to 5 (.) 10(-3), based on the search for catalysis events in the MACRO data. We also analyze the dependence of the MM flux limit on the catalysis cross section.

  • 248. Ambrosio, M
    et al.
    Antolini, R
    Auriemma, G
    Bakari, D
    Baldini, A
    Barbarino, G C
    Barish, B C
    Battistoni, G
    Becherini, Yvonne
    Università di Bologna, Italy ; INFN, Italy.
    Bellotti, R
    Bemporad, C
    Bernardini, P
    Bilokon, H
    Bloise, C
    Bower, C
    Brigida, M
    Bussino, S
    Cafagna, F
    Calicchio, M
    Campana, D
    Carboni, M
    Caruso, R
    Cecchini, S
    Cei, F
    Chiarella, V
    Choudhary, B C
    Coutu, S
    Cozzi, M
    De Cataldo, G
    Dekhissi, H
    De Marzo, C
    De Mitri, I
    Derkaoui, J
    De Vincenzi, M
    Di Credico, A
    Erriquez, O
    Favuzzi, C
    Forti, C
    Fusco, P
    Giacomelli, G
    Giannini, G
    Giglietto, N
    Giorgini, M
    Grassi, M
    Grillo, A
    Guarino, F
    Gustavino, C
    Habig, A
    Hanson, K
    Heinz, R
    Iarocci, E
    Katsavounidis, E
    Katsavounidis, I
    Kearns, E
    Kim, H
    Kyriazopoulou, S
    Lamanna, E
    Lane, C
    Levin, D S
    Lipari, P
    Longley, N P
    Longo, M J
    Loparco, F
    Maaroufi, F
    Mancarella, G
    Mandrioli, G
    Margiotta, A
    Marini, A
    Martello, D
    Marzari-Chiesa, A
    Mazziotta, M N
    Michael, D G
    Monacelli, P
    Montaruli, T
    Monteno, M
    Mufson, S
    Musser, J
    Nicolo, D
    Nolty, R
    Orth, C
    Osteria, G
    Palamara, O
    Patera, V
    Patrizii, L
    Pazzi, R
    Peck, C W
    Perrone, L
    Petrera, S
    Pistilli, P
    Popa, V
    Raino, A
    Reynoldson, J
    Ronga, F
    Rrhioua, A
    Satriano, C
    Scapparone, E
    Scholberg, K
    Sciubba, A
    Serra, P
    Sioli, M
    Sirri, G
    Sitta, M
    Spinelli, P
    Spinetti, M
    Spurio, M
    Steinberg, R
    Stone, J L
    Sulak, L R
    Surdo, A
    Tarle, G
    Togo, V
    Vakili, M
    Walter, C W
    Webb, R
    Search for cosmic ray sources using muons detected by the MACRO experiment2003In: Astroparticle physics, ISSN 0927-6505, E-ISSN 1873-2852, Vol. 18, no 6, p. 615-627Article in journal (Refereed)
    Abstract [en]

    The MACRO underground detector at Gran Sasso Laboratory recorded 60 million secondary cosmic ray muons from February 1989 until December 2000. Different techniques were used to analyze this sample in search for density excesses from astrophysical point-like sources. No evidence for DC excesses for any source in an all-sky survey is reported. In addition, searches for muon excess correlated with the known binary periods of Cygnus X-3 and Hercules X-1, and searches for statistically significant bursting episodes from known gamma-ray sources are also proved negative. (C) 2002 Elsevier Science B.V. All rights reserved.

  • 249. Ambrosio, M
    et al.
    Antolini, R
    Auriemma, G
    Bakari, D
    Baldini, A
    Barbarino, G C
    Barish, B C
    Battistoni, G
    Becherini, Yvonne
    Università di Bologna, Italy ; INFN, Italy.
    Bellotti, R
    Bemporad, C
    Bernardini, P
    Bilokon, H
    Bloise, C
    Bower, C
    Brigida, M
    Bussino, S
    Cafagna, F
    Calicchio, M
    Campana, D
    Carboni, M
    Caruso, R
    Cecchini, S
    Cei, F
    Chiarella, V
    Choudhary, B C
    Coutu, S
    Cozzi, M
    De Cataldo, G
    Dekhissi, H
    De Marzo, C
    De Mitri, I
    Derkaoui, J
    De Vincenzi, M
    Di Credico, A
    Erriquez, O
    Favuzzi, C
    Forti, C
    Fusco, P
    Giacomelli, G
    Giannini, G
    Giglietto, N
    Giorgini, M
    Grassi, M
    Grillo, A
    Guarino, F
    Gustavino, C
    Habig, A
    Hanson, K
    Heinz, R
    Iarocci, E
    Katsavounidis, E
    Katsavounidis, I
    Kearns, E
    Kim, H
    Kyriazopoulou, S
    Lamanna, E
    Lane, C
    Levin, D S
    Lipari, P
    Longley, N P
    Longo, M J
    Loparco, F
    Maaroufi, F
    Mancarella, G
    Mandrioli, G
    Margiotta, A
    Marini, A
    Martello, D
    Marzari-Chiesa, A
    Mazziotta, M N
    Michael, D G
    Monacelli, P
    Montaruli, T
    Monteno, M
    Mufson, S
    Musser, J
    Nicolo, D
    Nolty, R
    Orth, C
    Osteria, G
    Palamara, O
    Patera, V
    Patrizii, L
    Pazzi, R
    Peck, C W
    Perrone, L
    Petrera, S
    Pistilli, P
    Popa, V
    Raino, A
    Reynoldson, J
    Ronga, F
    Rrhioua, A
    Satriano, C
    Scapparone, E
    Scholberg, K
    Sciubba, A
    Serra, P
    Sioli, M
    Sirri, G
    Sitta, M
    Spinelli, P
    Spinetti, M
    Spurio, M
    Steinberg, R
    Stone, J L
    Sulak, L R
    Surdo, A
    Tarle, G
    Togo, V
    Vakili, M
    Walter, C W
    Webb, R
    Search for diffuse neutrino flux from astrophysical sources with MACRO2003In: Astroparticle physics, ISSN 0927-6505, E-ISSN 1873-2852, Vol. 19, no 1, p. 1-13Article in journal (Refereed)
    Abstract [en]

    Many galactic and extragalactic astrophysical sources are currently considered promising candidates as high-energy neutrino emitters. Astrophysical neutrinos can be detected as upward-going muons produced in charged-current interactions with the medium surrounding the detector. The expected neutrino fluxes from various models start to dominate on the atmospheric neutrino background at neutrino energies above some tens of TeV. We present the results of a search for an excess of high-energy upward-going muons among the sample of data collected by MACRO during similar to5.8 years of effective running time. No significant evidence for this signal was found. As a consequence, an upper limit on the flux of upward-going muons from high-energy neutrinos was set at the level of 1.7 x 10(-14) cm(-2) s(-1) sr(-1). The corresponding upper limit for the diffuse neutrino flux was evaluated assuming a neutrino power law spectrum. Our result was compared with theoretical predictions and upper limits from other experiments. (C) 2002 Elsevier Science B.V. All rights reserved.

  • 250.
    Ambrosio, M
    et al.
    Università di Napoli, Italy ; INFN, Italy.
    Antolini, R
    INFN, Italy.
    Auriemma, G
    Università di Roma “La Sapienza”, Italy ; INFN, Italy.
    Bakari, D
    Università di Bologna, Italy ; INFN, Italy ; University Mohamed I, Morocco.
    Baldini, A
    Università di Pisa, Italy ; INFN, Italy.
    Barbarino, G C
    Università di Napoli, Italy ; INFN, Italy.
    Barish, B C
    California Institute of Technology, USA.
    Battistoni, G
    INFN, Italy.
    Becherini, Yvonne
    Università di Bologna, Italy ; INFN, Italy.
    Bellotti, R
    Università di Bari, Italy ; INFN, Italy.
    Bemporad, C
    Bernardini, P
    Bilokon, H
    Bloise, C
    Bower, C
    Brigida, M
    Bussino, S
    Cafagna, F
    Calicchio, M
    Campana, D
    Carboni, M
    Caruso, R
    Cecchini, S
    Cei, F
    Chiarella, V
    Choudhary, B C
    Coutu, S
    De Cataldo, G
    Dekhissi, H
    De Marzo, C
    De Mitri, I
    Derkaoui, J
    De Vincenzi, M
    DiCredico, A
    Erriquez, O
    Favuzzi, C
    Forti, C
    Fusco, P
    Giacomelli, G
    Giannini, G
    Giglietto, N
    Giorgini, M
    Grassi, M
    Grillo, A
    Guarino, F
    Gustavino, C
    Habig, A
    Heinz, R
    Iarocci, E
    Katsavounidis, E
    Katsavounidis, I
    Kearns, E
    Kim, H
    Kyriazopoulou, S
    Lamanna, E
    Lane, C
    Levin, D S
    Lipari, P
    Longley, N P
    Longo, M J
    Loparco, F
    Maaroufi, F
    Mancarella, G
    Mandrioli, G
    Manzoor, S
    Margiotta, A
    Marini, A
    Martello, D
    Marzari-Chiesa, A
    Mazziotta, M N
    Michael, D G
    Monacelli, P
    Montaruli, T
    Monteno, M
    Mufson, S
    Musser, J
    Nicolo, D
    Nolty, R
    Orth, C
    Osteria, G
    Palamara, O
    Patera, V
    Patrizii, L
    Pazzi, R
    Peck, C W
    Perrone, L
    Petrera, S
    Popa, V
    Reynoldson, J
    Ronga, F
    Rrhioua, A
    Satriano, C
    Scapparone, E
    Scholberg, K
    Sciubba, A
    Serra, P
    Sioli, M
    Sirri, G
    Sitta, M
    Spinelli, P
    Spinetti, M
    Spurio, M
    Steinberg, R
    Stone, J L
    Sulak, L R
    Surdo, A
    Tarle, G
    Togo, V
    Vakili, M
    Walter, C W
    Webb, R
    A combined analysis technique for the search for fast magnetic monopoles with the MACRO detector2002In: Astroparticle physics, ISSN 0927-6505, E-ISSN 1873-2852, Vol. 18, no 1, p. 27-41Article in journal (Refereed)
    Abstract [en]

    We describe a search method for fast moving (beta = v/c > 5 x 10(-3)) magnetic monopoles using simultaneously the scintillator, streamer tube and track-etch subdetectors of the MACRO apparatus. The first two subdetectors are used primarily for the identification of candidates while the track-etch one is used as the final tool for their rejection or confirmation. Using this technique, a first sample of more than two-years of data has been analyzed without any evidence of a magnetic monopole. We set a 90% CL upper limit to the local monopole flux of 1.5 x 10(-15) cm(-2) s(-1) sr(-1) in the velocity range 5 x 10(-3) less than or equal to beta less than or equal to 0.99 and for nucleon decay catalysis cross-section smaller than similar to1 mb (C) 2002 Elsevier Science B.V. All rights reserved.

2345678 201 - 250 of 860
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