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  • 251. Ambrosio, M
    et al.
    Antolini, R
    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, E
    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
    Favuzzi, C
    Forti, C
    Fusco, P
    Giacomelli, G
    Giannini, G
    Giglietto, N
    Giorgini, M
    Grassi, M
    Grillo, A
    Gustavino, C
    Habig, A
    Hanson, K
    Heinz, R
    Iarocci, E
    Katsavounidis, E
    Katsavounidis, I
    Kearns, E
    Kim, H
    Kumar, A
    Kyriazopoulou, S
    Lamanna, E
    Lane, C
    Levin, D S
    Lipari, 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
    Mikheyev, S
    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
    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
    Atmospheric neutrino oscillations from upward throughgoing muon multiple scattering in MACRO2003In: Physics Letters B, ISSN 0370-2693, E-ISSN 1873-2445, Vol. 566, no 1-2, p. 35-44Article in journal (Refereed)
    Abstract [en]

    The energy of atmospheric neutrinos detected by MACRO was estimated using multiple Coulomb scattering of upward throughgoing muons. This analysis allows a test of atmospheric neutrino oscillations, relying on the distortion of the muon energy distribution. These results have been combined with those coming from the upward throughgoing muon angular distribution only. Both analyses are independent of the neutrino flux normalization and provide strong evidence, above the for level, in favour of neutrino oscillations. (C) 2003 Published by Elsevier B.V.

  • 252. Ambrosio, M
    et al.
    Antolini, R
    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
    Cafagna, F
    Campana, D
    Carboni, M
    Cecchini, S
    Cei, F
    Chiarella, V
    Choudhary, B C
    Cosson, D
    Coutu, S
    De Cataldo, G
    Dekhissi, H
    De Marzo, C
    De Mitri, I
    Denni, U
    Derkauoi, J
    De Vincenzi, M
    Di Credico, A
    Favuzzi, C
    Forti, C
    Frani, A
    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
    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
    Mengucci, A
    Michael, D G
    Mikheyev, S
    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
    Raino, A
    Reynoldson, J
    Ronga, F
    Satriano, C
    Scholberg, K
    Sciubba, A
    Sioli, M
    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
    Measurements of atmospheric muon neutrino oscillations, global analysis of the data collected with MACRO detector2004In: European Physical Journal C, ISSN 1434-6044, E-ISSN 1434-6052, Vol. 36, no 3, p. 323-339Article in journal (Refereed)
    Abstract [en]

    The final analysis of atmospheric neutrino events collected with the MACRO detector is presented. Three different classes of events, generated by neutrinos in different energy ranges, are studied looking at rates, angular distributions and estimated energies. The results are consistent for all the subsamples and indicate a flux deficit that depends on energy and path - length of neutrinos. The no - oscillation hypothesis is excluded at similar to 5sigma, while the hypothesis of nu(mu) --> nu(tau) oscillation gives a satisfactory description of all data. The parameters with highest probability in a two flavor scenario are sin(2) 2theta(m) = 1 and Deltam(2) = 0.0023 eV(2). This result is independent of the absolute normalization of the atmospheric neutrino fluxes. The data can also be used to put experimental constrain on this normalization.

  • 253. Ambrosio, M
    et al.
    Antolini, R
    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
    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
    Gustavino, C
    Habig, A
    Hanson, K
    Heinz, R
    Katsavounidis, E
    Katsavounidis, I
    Kearns, E
    Kim, H
    Kumar, A
    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
    Patrizii, L
    Pazzi, R
    Peck, C W
    Perrone, L
    Petrera, S
    Popa, V
    Raino, A
    Reynoldson, J
    Ronga, F
    Satriano, C
    Scapparone, E
    Scholberg, K
    Sioli, M
    Sirri, G
    Sitta, M S
    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
    Moon and Sun shadowing effect in the MACRO detector2003In: Astroparticle physics, ISSN 0927-6505, E-ISSN 1873-2852, Vol. 20, no 2, p. 145-156Article in journal (Refereed)
    Abstract [en]

    Using data collected by the MACRO experiment from 1989 to the end of its operations in 2000, we have studied in the underground muon flux the shadowing. effects due to both the Moon and the Sun. We have observed the shadow cast by the Moon at its apparent position with a significance of 6.5sigma. The Moon shadowing effect has been used to verify the pointing capability of the detector and to determine the instrument resolution for the search of muon excesses from any direction of the celestial sphere. The dependence of the effect on the geomagnetic field is clearly shown by splitting the data sample in day and night observations. The Sun shadow, observed with a significance of 4.6sigma is displaced by about 0.6degrees from its apparent position. In this case however the explanation resides in the configuration of the Solar and Interplanetary Magnetic Fields, which affect the propagation of cosmic ray particles between the Sun, and the Earth. The displacement of the Sun shadow with respect to the real Sun position has been used to establish an upper limit on the antimatter flux in cosmic rays of about 48% at 68% c.l. and primary energies of about 20 TeV. (C) 2003 Elsevier B.V. All rights reserved.

  • 254. Ambrosio, M
    et al.
    Antolini, R
    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
    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
    Gustavino, C
    Habig, A
    Hanson, K
    Heinz, R
    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
    Miller, L
    Monacelli, P
    Montaruli, T
    Monteno, M
    Mufson, S
    Musser, J
    Nicolo, D
    Nolty, R
    Orth, C
    Osteria, G
    Palamara, O
    Patrizii, L
    Pazzi, R
    Peck, C W
    Perrone, L
    Petrera, S
    Popa, V
    Raino, A
    Reynoldson, J
    Ronga, F
    Satriano, C
    Scapparone, E
    Scholberg, K
    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 the sidereal and solar diurnal modulations in the total MACRO muon data set2003In: Physical Review D. Particles and fields, ISSN 0556-2821, E-ISSN 1089-4918, Vol. 67, no 4, article id 042002Article in journal (Refereed)
    Abstract [en]

    We have analyzed 44.3M single muons collected by MACRO from 1991 through 2000 in 2145 live days of operation. We have searched for the solar diurnal, apparent sidereal, and pseudosidereal modulation of the underground muon rate by computing hourly deviations of the muon rate from 6 month averages. We find evidence for statistically significant modulations with the solar diurnal and the sidereal periods. The amplitudes of these modulations are <0.1%, and are at the limit of the detector statistics. The pseudosidereal modulation is not statistically significant. The solar diurnal modulation is due to the daily atmospheric temperature variations at 20 km, the altitude of primary cosmic ray interactions with the atmosphere; MACRO is the deepest experiment to report this result. The sidereal modulation is in addition to the expected Compton-Getting modulation due to solar system motion relative to the local standard of rest; it represents motion of the solar system with respect to the galactic cosmic rays toward the galactic plane.

  • 255. Ambrosio, M
    et al.
    Antolini, R
    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
    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, H
    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
    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
    Satraino, 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
    Vakili, M
    Walter, C W
    Webb, R
    Measurement of the residual energy of muons in the Gran Sasso underground laboratories2003In: Astroparticle physics, ISSN 0927-6505, E-ISSN 1873-2852, Vol. 19, no 3, p. 313-328Article in journal (Refereed)
    Abstract [en]

    The MACRO detector was located in the Hall B of the Gran Sasso underground laboratories under an average rock overburden of 3700 hg/cm(2). A transition radiation detector composed of three identical modules, covering a total horizontal area of 36 m(2), was installed inside the empty upper part of the detector in order to measure the residual energy of muons. This paper presents the measurement of the residual energy of single and double muons crossing the apparatus. Our data show that double muons are more energetic than single ones. This measurement is performed over a standard rock depth range from 3000 to 6500 hg/cm(2). (C) 2002 Elsevier Science B.V. All rights reserved.

  • 256.
    Andersson, Anders
    Växjö University, Faculty of Mathematics/Science/Technology, School of Mathematics and Systems Engineering. Matematik.
    Using a Zipper Algorithm to find a Conformal Map for a Channel with Smooth Boundary2006In: AIP Conference Proceedings: Second Conference on Mathematical Modeling of Wave Phenomena, American Institute of Physics, New York , 2006, p. 378-Conference paper (Refereed)
    Abstract [en]

    The so called geodesic algorithm, which is one of the zipper algorithms for conformal mappings, is combined with a Schwarz–Christoffel mapping, in its original or in a modified form, to produce a conformal mapping function between the upper half-plane and an arbitrary channel with smooth boundary and parallel walls at the end.

  • 257.
    Andersson, Anders
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Mathematics and Systems Engineering.
    Nilsson, Börje
    Växjö University, Faculty of Mathematics/Science/Technology, School of Mathematics and Systems Engineering.
    Acoustic Transmission in Ducts of Various Shapes with an Impedance Condition2008In: International Conference on Numerical Analysis and Applied Mathematics 2008, AIP, Melville, USA , 2008, p. 33-36Conference paper (Refereed)
    Abstract [en]

    Propagation of acoustic waves in a two-dimensional duct with an impedance condition at the boundary, is studied. The duct is assumed to have two ends at infinity being asymptotically straight, but otherwise to be arbitrarily shaped.The so called Building Block Method allows us to synthesize propagation properties for ducts with complicated geometries from results for simpler ducts. Conformal mappings can be used to transform these simple ducts to straight ducts with constant cross-sections.By using recently developed techniques for numerical conformal mappings, it is possible to construct a transformation between an infinite strip and an arbitrarily shaped duct with smooth or piecewise smooth boundary, keeping both smoothness and the well controlled boundary direction towards infinity that the above mentioned method requires.To accomplish a stable formulation of the problem, we express it in terms of scattering operators. The resulting differential equation is solved using wave splitting and invariant embedding techniques. We expand the involved functions in Fourier series, and hence, it is possible to give the operators a matrix representation. Numerical results are produced using truncated matrices.

  • 258. Andersson, B.
    et al.
    Gustafson, G.
    Nilsson, A.
    Sjögren, C.
    Fluctuations and anomalous dimensions in QCD cascades1991In: Z. Phys. C - Particles and Fields, ISSN 0170-9739, Vol. 49, no 1, p. 79-89Article in journal (Refereed)
  • 259. Andersson, B.
    et al.
    Gustafson, G.
    Sjögren, C.
    Comparison of the dipole cascade model versus O(aS2) matrix elements and colour interference  in  e+ e- annihilation1992In: Nuclear Physics B, ISSN 0550-3213, E-ISSN 1873-1562, Vol. 380, no 3, p. 391-407Article in journal (Refereed)
  • 260. Andersson, B.
    et al.
    Gustafson, G.
    Sjögren, C.
    Prompt photon production in e+ e- annihilation1992In: Nuclear Physics B, ISSN 0550-3213, E-ISSN 1873-1562, Vol. 380, no 3, p. 408-422Article in journal (Refereed)
  • 261. Andersson, B.
    et al.
    Gustafson, G.
    Sjögren, C.
    LNU.
    Prompt photons in e+ e- annihilation reactions1992In: Proceedings of Workshop on photon radiation from quarks / [ed] S. Cartwright, CERN , 1992, p. 74-88Conference paper (Other academic)
  • 262.
    Andersson, Tom
    Linnaeus University, Faculty of Technology, Department of Physics and Electrical Engineering.
    Inverse Compton gamma-rays from Markarian 421: A study of GeV and TeV emission from Mrk 421 based on Fermi-LAT and H.E.S.S. data2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis summarizes a senior project on the Active Galactic Nucleus (AGN) Markarian 421 (Mrk 421). Observations of Gev and TeV flux with Fermi Large Area Telescope (LAT) and High Energy Stereoscopic System (H.E.S.S.) were compared with previous reports and publications of flux analyses of the gamma-ray emission from Mrk 421. Power laws with exponential cutoffs made consistent fits to most SEDs in the GeV and TeV bands.

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  • 263. Andres, E.
    et al.
    Askebjer, P.
    Bai, X.
    Barouch, G.
    Barwick, S. W.
    Bay, R. C.
    Becker, K. H.
    Bergstrom, L.
    Bertrand, D.
    Bierenbaum, 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.
    Dailing, J.
    Dalberg, E.
    DeYoung, T.
    Desiati, P.
    Dewulf, J. P.
    Doksus, P.
    Edsjo, J.
    Ekstrom, P.
    Erlandsson, B.
    Feser, T.
    Gaug, M.
    Goldschmidt, A.
    Goobar, A.
    Gray, L.
    Haase, H.
    Hallgren, A.
    Halzen, F.
    Hanson, K.
    Hardtke, R.
    He, Y. D.
    Hellwig, M.
    Heukenkamp, H.
    Hill, G. C.
    Hulth, P. O.
    Hundertmark, S.
    Jacobsen, J.
    Kandhadai, V.
    Karle, A.
    Kim, J.
    Koci, B.
    Kopke, L.
    Kowalski, M.
    Leich, H.
    Leuthold, M.
    Lindahl, P.
    University of Kalmar, Department of Technology.
    Liubarsky, I.
    Loaiza, P.
    Lowder, D. M.
    Ludvig, J.
    Madsen, J.
    Marciniewski, P.
    Matis, H. S.
    Mihalyi, A.
    Mikolajski, T.
    Miller, T. C.
    Minaeva, Y.
    Miocinovic, P.
    Mock, P. C.
    Morse, R.
    Neunhoffer, T.
    Newcomer, F. M.
    Niessen, P.
    Nygren, D. R.
    Ogelman, H.
    Peres de los Heros, C. P. D. L.
    Porrata, R.
    Price, P. B.
    Rawlins, K.
    Reed, C.
    Rhode, W.
    Richards, A.
    Richter, S.
    Martino, J. R.
    Romenesko, P.
    Ross, D.
    Rubinstein, H.
    Sander, H. G.
    Scheider, T.
    Schmidt, T.
    Schneider, D.
    Schneider, E.
    Schwarzl, R.
    Silvestri, A.
    Solarz, M.
    Spiczak, G. M.
    Spiering, C.
    Starinsky, N.
    Steele, D.
    Steffen, P.
    Stokstad, R. G.
    Streicher, O.
    Sun, A.
    Taboada, I.
    Thollander, L.
    Thon, T.
    Tilav, S.
    Usechak, N.
    Donckt, M. V.
    Walck, C.
    Weinheimer, C.
    Wiebusch, C. H.
    Wischnewski, R.
    Wissing, H.
    Woschnagg, K.
    Wu, W.
    Yodh, G.
    Young, S.
    Lim, C. S.
    Yamanaka, T.
    Selected recent results from AMANDA2001In: ICHEP 2000. Proceedings of the 30th International Conference on High Energy Physics / [ed] Lim, C.S., Yamanaka, T., World Scientific, 2001, p. 965-968Conference paper (Refereed)
    Abstract [en]

    We present a selection of results based on data taken in 1997 with the 302-PMT Antarctic Muon and Neutrino Detector Array-B10 ("AMANDA-B10") array. Atmospheric neutrinos created in the northern hemisphere are observed indirectly through their charged current interactions which produce relativistic, Cherenkov-light-emitting upgoing muons in the South Pole ice cap. The reconstructed angular distribution of these events is in good agreement with expectation and demonstrates the viability of this ice-based device as a neutrino telescope. Studies of nearly vertical upgoing muons limit the available parameter space for WIMP dark matter under the assumption that WIMPS are trapped in the earth's gravitational potential well and annihilate with one another near the earth's center.

  • 264. Andres, E.
    et al.
    Askebjer, P.
    Bai, X.
    Barouch, G.
    Barwick, S. W.
    Bay, R. C.
    Becker, K. -H
    Bergström, L.
    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.
    Chirkin, D.
    Conrad, J.
    Costa, C. G. S.
    Cowen, D. F.
    Dailing, J.
    Dalberg, E.
    DeYoung, T.
    Desiati, P.
    Dewulf, J. -P
    Doksus, P.
    Edsjö, J.
    Ekström, P.
    Erlandsson, B.
    Feser, T.
    Gaug, M.
    Goldschmidt, A.
    Goobar, A.
    Haase, H.
    Hallgren, A.
    Halzen, F.
    Hanson, K.
    Hardtke, R.
    He, Y. D.
    Hellwig, M.
    Heukenkamp, H.
    Hill, G. C.
    Hulth, P. O.
    Hundertmark, S.
    Jacobsen, J.
    Karle, A.
    Kim, J.
    Koci, B.
    Köpke, L.
    Kowalski, M.
    Leich, H.
    Leuthold, M.
    Lindahl, P.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Liubarsky, I.
    Loaiza, P.
    Lowder, D. M.
    Ludvig, J.
    Madsen, J.
    Marciniewski, P.
    Matis, H.
    Mikolajski, T.
    Miller, T. C.
    Minaeva, Y.
    Miocinovic, P.
    Mock, P.
    Morse, R.
    Neunhöffer, T.
    Newcomer, F. M.
    Niessen, P.
    Nygren, D. R.
    Pérez de los Heros, C.
    Porrata, R.
    Price, P. B.
    Rawlins, K.
    Reed, C.
    Rhode, W.
    Richards, A.
    Richter, S.
    Rodriguez Martino, J.
    Romenesko, P.
    Ross, D.
    Rubinstein, H.
    Sander, H. -G
    Scheider, T.
    Schmidt, T.
    Schneider, D.
    Schneider, E.
    Schwarz, R.
    Silvestri, A.
    Solarz, M.
    Spiczak, G.
    Spiering, C.
    Starinski, N.
    Steele, D.
    Steffen, P.
    Stokstad, R. G.
    Streicher, O.
    Sun, Q.
    Taboada, I.
    Thollander, L.
    Thon, T.
    Tilav, S.
    Vander Donckt, M.
    Walck, C.
    Weinheimer, C.
    Wiebusch, C. H.
    Wischnewski, R.
    Woschnagg, K.
    Wu, W.
    Yodh, G.
    Young, S.
    Results from the AMANDA high energy neutrino detector2000In: Nuclear physics B, Proceedings supplements, ISSN 0920-5632, E-ISSN 1873-3832, Vol. 91, no 1-3, p. 423-430Article in journal (Refereed)
    Abstract [en]

    This paper briefly summarizes the search for astronomical sources of high-energy neutrinos using the AMANDA-B10 detector. The complete data set from 1997 was analyzed. For Eμ &gt; 10 TeV, the detector exceeds 10,000 m2 in effective area between declinations of 25 and 90 degrees. Neutrinos generated in the atmosphere by cosmic ray interactions were used to verify the overall sensitivity of the detector. The absolute pointing accuracy and angular resolution has been confirmed by the analysis of coincident events between the SPASE air shower array and the AMANDA detector. Preliminary flux limits from point source candidates are presented. For declinations larger than +45 degrees, our results compare favorably to existing limits for sources in the Southern sky. We also present the current status of the searches for high energy neutrino emission from diffusely distributed sources, GRBs, and WIMPs from the center of the earth.

  • 265. Andres, E.
    et al.
    Askebjer, P.
    Barouch, G.
    Barwick, S.
    Bai, X.
    Becker, K.
    Bay, R.
    Bergström, L.
    Bertrand, D.
    Besson, D.
    Biron, A.
    Booth, J.
    Bothner, O.
    Bouchta, A.
    Carius, Staffan
    University of Kalmar, Department of Technology.
    Carlson, M.
    Chinowsky, W.
    Chirkin, D.
    Conrad, J.
    Costa, C.
    Cowen, D. F.
    Dahlberg, E.
    Dewulf, J.
    DeYoung, T.
    Edsjö, J.
    Ekström, P.
    Frichter, G.
    Goobar, A.
    Gray, L.
    Hallgren, A.
    Halzen, F.
    He, Y.
    Hardtke, R.
    Hill, G.
    Hulth, P.O.
    Hundertmark, S.
    Jacobsen, J.
    Kandhadai, V.
    Karle, A.
    Kim, J.
    Kroci, B.
    Kowalski, M.
    Kravchenko, I.
    Lamoureux, J.
    Loaiza, P.
    Leich, H.
    Lindahl, P.
    University of Kalmar, Department of Technology.
    Liss, T.
    Liubarsky, I.
    Leuthold, M.
    Lowder, D.M.
    Ludvig, J.
    Marciniewski, P.
    Miller, T.
    Miocinovic, P.
    Mock, P.
    Newcomer, F. M.
    Morse, R.
    Niessen, P.
    Nygren, D.
    Perez de los Heros, C.
    Porrata, R.
    Price, P. B.
    Przybylski, G.
    Rawlins, K.
    Rhode, W.
    Richter, S.
    Rodriguez Martino, J.
    Romenesko, P.
    Ross, D.
    Rubenstein, H.
    Schneider, E.
    Schmidt, T.
    Schwarz, R.
    Silvestri, A.
    Smoot, G.
    Solarz, M.
    Spiczak, G.
    Spiering, C.
    Starinski, N.
    Steffen, P.
    Stokstad, R.
    Streicher, O.
    Taboada, I.
    Thon, T.
    Tilav, S.
    Vander Donckt, M.
    Walck, C.
    Wiebusch, C.
    Wischnewski, R.
    Woschnagg, K.
    Wu, W.
    Yodh, G.
    Young, S.
    AMANDA: Status, results and future1999In: Proceedings, 8th International Workshop, Venice, Italy, February 23-26, 1999. Vol. 1, 2 / [ed] M.Baldo-Ceolin, 1999, p. 63-79Conference paper (Refereed)
    Abstract [en]

    We review the status of the AMANDA neutrino telescope. We present resultsobtained from the four-string prototype array AMANDA-B4 and describe themethods of track reconstruction and neutrino event separation. We give also firstresults of the analysis of the 10-string detector AMANDA-B10, in particular onatmospheric neutrinos and the search for magnetic monopoles. We sketch thefuture schedule on the way to a cube kilometer telescope at the South Pole,ICECUBE.

  • 266. Andres, E.
    et al.
    Askebjer, P.
    Barouch, G.
    Barwick, S. W.
    Bai, X.
    Bay, R.
    Becker, K.
    Bergstrom, L.
    Bertrand, D.
    Besson, D.
    Biron, A.
    Booth, J.
    Bothner, O.
    Bouchta, A.
    Carius, Staffan
    University of Kalmar, Department of Technology.
    Carlson, M.
    Chinowsky, W.
    Chirkin, D.
    Conrad, Jan
    Costa, C.
    Cowen, D.
    Dahlberg, E.
    Dewulf, J.
    DeYoung, T.
    Edsjo, P.
    Ekstrom, P.
    Frichter, G.
    Goodbar, A.
    Gray, L.
    Hallgren, A.
    Halzen, F.
    He, Y.
    Hardtke, R.
    Hill, G.
    Hulth, P.O.
    Hundertmark, S.
    Jacobsen, J.
    Kandhadai, V.
    Karle, A.
    Kim, J.
    Koci, B.
    Kowalaski, M.
    Kravchenko, I.
    Lamoureux, J.
    Loaiza, P.
    Leich, P.
    Lindahl, P.
    University of Kalmar, Department of Technology.
    Liss, Tony M.
    Liubarsky, I.
    Leuthold, M.
    Lowder, D.M.
    Ludvig, J.
    Marciniewski, P.
    Miller, T.
    Miocinovic, P.
    Mock, P.
    Newcomer, M.
    Morse, R.
    Niessen, P.
    Nygren, D.
    Perez de los Heros, C.
    Porrata, R.
    Price, P. B.
    Przybylski, G.
    Rawlins, K.
    Rhodes, W.
    Richter, S.
    Rodriguez Martino, J.
    Romenesko, P.
    Ross, D.
    Rubenstein, H.
    Schneider, E.
    Schmidt, T.
    Schwartz, R.
    Silvestri, A.
    Smoot, George F.
    Solarz, M.
    Spiczak, G.
    Spiering, C.
    Starinski, N.
    Steffen, P.
    Stokstad, R.
    Streicher, O.
    Taboada, I.
    Thon, T.
    Tilav, S.
    Vander Donckt, M.
    Walck, C.
    Wiebusch, C.
    Wischnewski, R.
    Woschnagg, K.
    Wu, W.
    Yodh, G.
    Young, S.
    Observation of atmospheric neutrino events with the AMANDA experiment2000In: Proceedings of the 17th International Workshop on Weak Interactions and Neutrinos: Cape Town, South Africa, 24-30 January 1999 / [ed] Vollier R. D., Dominiguez C. A., World Scientific, 2000, p. 258-262Conference paper (Refereed)
  • 267. Andres, E.
    et al.
    Askebjer, P.
    Barwick, S. W.
    Bay, R.
    Bergström, L.
    Biron, A.
    Booth, J.
    Bouchta, A.
    Carius, Staffan
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Carlson, M.
    Cowen, D.
    Dalberg, E.
    Deyoung, T.
    Ekström, P.
    Erlandson, B.
    Goobar, A.
    Gray, L.
    Hallgren, A.
    Halzen, F.
    Hardtke, R.
    Hart, S.
    He, Y.
    Heukenkamp, H.
    Hill, G.
    Hulth, P. O.
    Hundertmark, S.
    Jacobsen, J.
    Jones, A.
    Kandhadai, V.
    Karle, A.
    Koci, B.
    Lindahl, P.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Liubarsky, I.
    Leuthold, M.
    Lowder, D. M.
    Marciniewski, P.
    Mikolajski, T.
    Miller, T.
    Miocinovic, P.
    Mock, P.
    Morse, R.
    Niessen, P.
    Pérez De Los Heros, C.
    Porrata, R.
    Potter, D.
    Price, P. B.
    Przybylski, G.
    Richards, A.
    Richter, S.
    Romenesko, P.
    Rubinstein, H.
    Schneider, E.
    Schmidt, T.
    Schwarz, R.
    Solarz, M.
    Spiczak, G. M.
    Spiering, C.
    Streicher, O.
    Sun, Q.
    Thollander, L.
    Thon, T.
    Tilav, S.
    Walck, C.
    Wiebusch, C.
    Wischnewski, R.
    Woschnagg, K.
    Yodh, G.
    The AMANDA neutrino telescope: Principle of operation and first results2000In: Astroparticle physics, ISSN 0927-6505, E-ISSN 1873-2852, Vol. 13, no 1, p. 1-20Article in journal (Refereed)
    Abstract [en]

    AMANDA is a high-energy neutrino telescope presently under construction at the geographical South Pole. In the Antarctic summer 1995/96, an array of 80 optical modules (OMs) arranged on 4 strings (AMANDA-B4) was deployed at depths between 1.5 and 2 km. In this paper we describe the design and performance of the AMANDA-B4 prototype, based on data collected between February and November 1996. Monte Carlo simulations of the detector response to down-going atmospheric muon tracks show that the global behavior of the detector is understood. We describe the data analysis method and present first results on atmospheric muon reconstruction and separation of neutrino candidates. The AMANDA array was upgraded with 216 OMs on 6 new strings in 1996/97 (AMANDA-B10), and 122 additional OMs on 3 strings in 1997/98.

  • 268. Andrés, E.
    et al.
    Askebjer, P.
    Bai, X.
    Barouch, G.
    Barwick, S. W.
    Bay, R. C.
    Becker, K. -H
    Bergström, L.
    Bertrand, D.
    Bierenbaum, 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.
    Dailing, J.
    Dalberg, E.
    De Young, T.
    Desiati, P.
    Dewulf, J. -P
    Doksus, P.
    Edsjö, J.
    Ekström, P.
    Erlandsson, B.
    Feser, T.
    Gaug, M.
    Goldschmidt, A.
    Goobar, A.
    Gray, L.
    Haase, H.
    Hallgren, A.
    Halzen, F.
    Hanson, K.
    Hardtke, R.
    He, Y. D.
    Hellwig, M.
    Heukenkamp, H.
    Hill, G. C.
    Hulth, P. O.
    Hundertmark, S.
    Jacobsen, J.
    Kandhadai, V.
    Karle, A.
    Kim, J.
    Koci, B.
    Köpke, L.
    Kowalski, M.
    Leich, H.
    Leuthold, M.
    Lindahl, P.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Liubarsky, I.
    Loaiza, P.
    Lowder, D. M.
    Ludvig, J.
    Madsen, J.
    Marciniewski, P.
    Matis, H. S.
    Mihalyi, A.
    Mikolajski, T.
    Miller, T. C.
    Minaeva, Y.
    Miočinović, P.
    Mock, P. C.
    Morse, R.
    Neunhöffer, T.
    Newcomer, F. M.
    Niessen, P.
    Nygren, D. R.
    Ogelman, H.
    Pérez De Los Heros, C.
    Porrata, R.
    Price, P. B.
    Rawlins, K.
    Reed, C.
    Rhode, W.
    Richards, A.
    Richter, S.
    Rodríguez Martino, J.
    Romenesko, P.
    Ross, D.
    Rubinstein, H.
    Sander, H. -G
    Scheider, T.
    Schmidt, T.
    Schneider, D.
    Schneider, E.
    Schwarz, R.
    Silvestri, A.
    Solarz, M.
    Spiczak, G. M.
    Spiering, C.
    Starinsky, N.
    Steele, D.
    Steffen, P.
    Stokstad, R. G.
    Streicher, O.
    Sun, Q.
    Taboada, I.
    Thollander, L.
    Thon, T.
    Tilav, S.
    Usechak, N.
    Vander Donckt, M.
    Walck, C.
    Weinheimer, C.
    Wiebusch, C. H.
    Wischnewski, R.
    Wissing, H.
    Woschnagg, K.
    Wu, W.
    Yodh, G.
    Young, S.
    Recent results from AMANDA2001In: International Journal of Modern Physics A, ISSN 0217-751X, E-ISSN 1793-656X, Vol. 16, no 1C, p. 1013-1015Article in journal (Refereed)
    Abstract [en]

    We present results based on data taken in 1997 with the 302-PMT Antarctic Muon and Neutrino Detector Array-B10 ("AMANDA-B10") array. Atmospheric neutrinos created in the northern hemisphere are observed indirectly through their charged current interactions which produce relativistic, Cherenkov-light-emitting upgoing muons in the South Pole ice cap. The reconstructed angular distribution of these events is in good agreement with expectation and demonstrates the viability of this ice-based device as a neutrino telescope.

  • 269. Andrés, E.
    et al.
    Askebjer, P.
    Bai, X.
    Barouch, G.
    Barwick, S. W.
    Bay, R. C.
    Becker, K. -H
    Bergström, L.
    Bertrand, D.
    Bierenbaum, 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.
    Dailing, J.
    Dalberg, E.
    DeYoung, T.
    Desiati, P.
    Dewulf, J. -P
    Doksus, P.
    Edsjö, J.
    Ekström, P.
    Erlandsson, B.
    Feser, T.
    Gaug, M.
    Goldschmidt, A.
    Goobar, A.
    Gray, L.
    Haase, H.
    Hallgren, A.
    Halzen, F.
    Hanson, K.
    Hardtke, R.
    He, Y. D.
    Hellwig, M.
    Heukenkamp, H.
    Hill, G. C.
    Hulth, P. O.
    Hundertmark, S.
    Jacobsen, J.
    Kandhadai, V.
    Karle, A.
    Kim, J.
    Koci, B.
    Köpke, L.
    Kowalski, M.
    Leich, H.
    Leuthold, M.
    Lindahl, P.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Liubarsky, I.
    Loaiza, P.
    Lowder, D. M.
    Ludvig, J.
    Madsen, J.
    Marciniewski, P.
    Matis, H. S.
    Mihalyi, A.
    Mikolajski, T.
    Miller, T. C.
    Minaeva, Y.
    Miočinović, P.
    Mock, P. C.
    Morse, R.
    Neunhöffer, T.
    Newcomer, F. M.
    Niessen, P.
    Nygren, D. R.
    Ögelman, H.
    Pérez De Los Heros, C.
    Porrata, R.
    Price, P. B.
    Rawlins, K.
    Reed, C.
    Rhode, W.
    Richards, A.
    Richter, S.
    Martino, J. R.
    Romenesko, P.
    Ross, D.
    Rubinstein, H.
    Sander, H. -G
    Scheider, T.
    Schmidt, T.
    Schneider, D.
    Schneider, E.
    Schwarz, R.
    Silvestri, A.
    Solarz, M.
    Spiczak, G. M.
    Spiering, C.
    Starinsky, N.
    Steele, D.
    Steffen, P.
    Stokstad, R. G.
    Streicher, O.
    Sun, Q.
    Taboada, I.
    Thollander, L.
    Thon, T.
    Tilav, S.
    Usechak, N.
    Vander Donckt, M.
    Walck, C.
    Weinheimer, C.
    Wiebusch, C. H.
    Wischnewski, R.
    Wissing, H.
    Woschnagg, K.
    Wu, W.
    Yodh, G.
    Young, S.
    Observation of high-energy neutrinos using Čerenkov detectors embedded deep in Antarctic ice2001In: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 410, no 6827, p. 441-443Article in journal (Refereed)
    Abstract [en]

    Neutrinos are elementary particles that carry no electric charge and have little mass. As they interact only weakly with other particles, they can penetrate enormous amounts of matter, and therefore have the potential to directly convey astrophysical information from the edge of the Universe and from deep inside the most cataclysmic high-energy regions. The neutrino's great penetrating power, however, also makes this particle difficult to detect. Underground detectors have observed low-energy neutrinos from the Sun and a nearby supernova2, as well as neutrinos generated in the Earth's atmosphere. But the very low fluxes of high-energy neutrinos from cosmic sources can be observed only by much larger, expandable detectors in, for example, deep water3,4 or ice5. Here we report the detection of upwardly propagating atmospheric neutrinos by the ice-based Antarctic muon and neutrino detector array (AMANDA). These results establish a technology with which to build a kilometre-scale neutrino observatory necessary for astrophysical observations1.

  • 270. Andrés, E.
    et al.
    Askebjer, P.
    Barwick, S. W.
    Bay, R.
    Bergström, L.
    Bouchta, A.
    Biron, A.
    Carius, Staffan
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Costa, C.
    Cowen, D.
    Dalberg, E.
    Ekström, P.
    Goobar, A.
    Gray, L.
    Hallgren, A.
    Halzen, F.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Hart, S.
    He, Y.
    Hill, G.
    Hulth, P. O.
    Hundertmark, S.
    Jacobsen, J.
    Jones, A.
    Kandahai, V.
    Karle, A.
    Lindahl, P.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Liubarsky, I.
    Lowder, D. M.
    Marciniewski, P.
    Mikolajski, T.
    Miller, T.
    Mock, P.
    Morse, R.
    Niessen, P.
    Nygren, D.
    Perez de Los Heros, C.
    Porrata, R.
    Potter, D.
    Price, P. B.
    Richards, A.
    Rubinstein, H.
    Schneider, E.
    Schwarz, R.
    Spiering, C.
    Streicher, O.
    Thon, T.
    Tilav, S.
    Walck, C.
    Wiebusch, C.
    Wischnewski, R.
    Woschnagg, K.
    Yodh, G.
    Status of the AMANDA experiment1999In: Nuclear physics B, Proceedings supplements, ISSN 0920-5632, E-ISSN 1873-3832, Vol. 70, no 1-3, p. 448-452Article in journal (Refereed)
    Abstract [en]

    The AMANDA high energy neutrino telescope has successfully been increased in size from four detector strings to ten detector strings during the 1996/1997 season. The first upward going muon-neutrino candidates have been reconstructed from the 1996 year's four-string data. Three new detector strings will be deployed during 1997/1998 to 2350 metres depth.

  • 271. Andrés, E. C.
    et al.
    Askebjer, P.
    Barwick, S. W.
    Bay, R. C.
    Bergström, L.
    Biron, A.
    Booth, J.
    Botner, O.
    Bouchta, A.
    Carius, Staffan
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Carlson, M.
    Chinowsky, W.
    Chirkin, D.
    Conrad, J.
    Costa, C. G. S.
    Cowen, D.
    Dalberg, E.
    DeYoung, T.
    Edsjö, J.
    Ekström, P.
    Goobar, A.
    Gray, L.
    Hallgren, A.
    Halzen, F.
    Hardtke, R.
    Hart, S.
    He, Y.
    De Los Heros, C. P.
    Hill, G.
    Hulth, P. O.
    Hundertmark, S.
    Jacobsen, J.
    Jones, A.
    Kandhadai, V.
    Karle, A.
    Kim, J.
    Leich, H.
    Leuthold, M.
    Lindahl, P.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Liubarsky, I.
    Loaiza, P.
    Lowder, D.
    Marciniewski, P.
    Miller, T. C.
    Miocinovic, P.
    Mock, P. C.
    Morse, R.
    Newcomer, M.
    Niessen, P.
    Nygren, D.
    Porrata, R.
    Potter, D.
    Price, P. B.
    Przybylski, G.
    Rhode, W.
    Richter, S.
    Rodriguez, J.
    Romenesko, P.
    Ross, D.
    Rubinstein, H.
    Schmidt, T.
    Schneider, E.
    Schwarz, R.
    Schwendicke, U.
    Smoot, G.
    Solarz, M.
    Sorin, V.
    Spiering, C.
    Steffen, P.
    Stokstad, R.
    Streicher, O.
    Taboada, I.
    Thon, T.
    Tilav, S.
    Walck, C.
    Wiebusch, C. H.
    Wischnewski, R.
    Woschnagg, K.
    Wu, W.
    Yodh, G.
    Young, S.
    The AMANDA neutrino telescope1999In: Nuclear physics B, Proceedings supplements, ISSN 0920-5632, E-ISSN 1873-3832, Vol. 77, no 1-3, p. 474-485Article in journal (Refereed)
    Abstract [en]

    With an effective telescope area of order 104 m2 for TeV neutrinos, a threshold near ∼50 GeV and a pointing accuracy of 2.5 degrees per muon track, the AMANDA detector represents the first of a new generation of high energy neutrino telescopes, reaching a scale envisaged over 25 years ago. We describe early results on the calibration of natural deep ice as a particle detector as well as on AMANDA's performance as a neutrino telescope.

  • 272.
    Antoniouk, Alexandra, V
    et al.
    Natl Acad Sci Ukraine, Ukraine.
    Oleschko, Klaudia
    UNAM, Mexico.
    Kochubei, Anatoly N.
    Natl Acad Sci Ukraine, Ukraine.
    Khrennikov, Andrei
    Linnaeus University, Faculty of Technology, Department of Mathematics.
    A stochastic p-adic model of the capillary flow in porous random medium2018In: Physica A: Statistical Mechanics and its Applications, ISSN 0378-4371, E-ISSN 1873-2119, Vol. 505, p. 763-777Article in journal (Refereed)
    Abstract [en]

    We develop the p-adic model of propagation of fluids (e.g., oil or water) in capillary networks in a porous random medium. The hierarchic structure of a system of capillaries is mathematically modeled by endowing trees of capillaries with the structure of an ultra metric space. Considerations are restricted to the case of idealized networks represented by homogeneous p-trees with p branches leaving each vertex, where p > 1 is a prime number. Such trees are realized as the fields of p-adic numbers. We introduce and study an inhomogeneous Markov process describing the penetration of fluid into a porous random medium. (C) 2018 Elsevier B.V. All rights reserved.

  • 273. Archambault, S.
    et al.
    Arlen, T.
    Aune, T.
    Behera, B.
    Beilicke, M.
    Benbow, W.
    Bird, R.
    Bouvier, A.
    Buckley, J. H.
    Bugaev, V.
    Byrum, K.
    Cesarini, A.
    Ciupik, L.
    Connolly, M. P.
    Cui, W.
    Errando, M.
    Falcone, A.
    Federici, S.
    Feng, Q.
    Finley, J. P.
    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.
    Kumar, S.
    Lang, M. J.
    Madhavan, A. S.
    Maier, G.
    Majumdar, P.
    McArthur, S.
    McCann, A.
    Millis, J.
    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.
    Reyes, L. C.
    Reynolds, P. T.
    Richards, G. T.
    Roache, E.
    Saxon, D. B.
    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.
    Zitzer, B.
    Collaboration, V E R I T A S
    Böttcher, M.
    Fegan, S. J.
    Fortin, P.
    Halpern, J. P.
    Kovalev, Y. Y.
    Lister, M. L.
    Liu, J.
    Pushkarev, A. B.
    Smith, P. S.
    Discovery of a New TeV Gamma-Ray Source: VER J0521+2112013In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 776, no 2, article id 69Article in journal (Refereed)
    Abstract [en]

    We report the detection of a new TeV gamma-ray source, VER J0521+211, based on observations made with the VERITAS imaging atmospheric Cherenkov Telescope Array. These observations were motivated by the discovery of a cluster of >30 GeV photons in the first year of Fermi Large Area Telescope observations. VER J0521+211 is relatively bright at TeV energies, with a mean photon flux of (1.93 ± 0.13stat ± 0.78sys× 10–11 cm–2 s–1 above 0.2 TeV during the period of the VERITAS observations. The source is strongly variable on a daily timescale across all wavebands, from optical to TeV, with a peak flux corresponding to ~0.3 times the steady Crab Nebula flux at TeV energies. Follow-up observations in the optical and X-ray bands classify the newly discovered TeV source as a BL Lac-type blazar with uncertain redshift, although recent measurements suggest z = 0.108. VER J0521+211 exhibits all the defining properties of blazars in radio, optical, X-ray, and gamma-ray wavelengths.

  • 274. Archambault, S.
    et al.
    Aune, T.
    Behera, B.
    Beilicke, M.
    Benbow, W.
    Berger, K.
    Bird, R.
    Biteau, J.
    Bugaev, V.
    Byrum, K.
    Cardenzana, J. V.
    Cerruti, M.
    Chen, X.
    Ciupik, L.
    Connolly, M. P.
    Cui, W.
    Dumm, J.
    Errando, M.
    Falcone, A.
    Federici, S.
    Feng, Q.
    Finley, J. P.
    Fleischhack, H.
    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.
    Kumar, S.
    Lang, M. J.
    Madhavan, A. S.
    Maier, G.
    McCann, A.
    Meagher, K.
    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 .
    Quinn, J.
    Ragan, K.
    Rajotte, J.
    Reyes, L. C.
    Reynolds, P. T.
    Richards, G. T.
    Roache, E.
    Sembroski, G. H.
    Shahinyan, K.
    Staszak, D.
    Telezhinsky, I.
    Tucci, J. V.
    Tyler, J.
    Varlotta, A.
    Vassiliev, V. V.
    Vincent, S.
    Wakely, S. P.
    Weinstein, A.
    Welsing, R.
    Wilhelm, A.
    Williams, D. A.
    Collaboration, V E R I T A S
    Ackermann, M.
    Ajello, M.
    Albert, A.
    Baldini, L.
    Bastieri, D.
    Bellazzini, R.
    Bissaldi, E.
    Bregeon, J.
    Buehler, R.
    Buson, S.
    Caliandro, G. A.
    Cameron, R. A.
    Caraveo, P. A.
    Cavazzuti, E.
    Charles, E.
    Chiang, J.
    Ciprini, S.
    Claus, R.
    Cutini, S.
    D’Ammando, F.
    de Angelis, A.
    de Palma, F.
    Dermer, C. D.
    Digel, S. W.
    Di Venere, L.
    Drell, P. S.
    Favuzzi, C.
    Franckowiak, A.
    Fusco, P.
    Gargano, F.
    Gasparrini, D.
    Giglietto, N.
    Giordano, F.
    Giroletti, M.
    Grenier, I. A.
    Guiriec, S.
    Jogler, T.
    Kuss, M.
    Larsson, S.
    Latronico, L.
    Longo, F.
    Loparco, F.
    Lubrano, P.
    Madejski, G. M.
    Mayer, M.
    Mazziotta, M. N.
    Michelson, P. F.
    Mizuno, T.
    Monzani, M. E.
    Morselli, A.
    Murgia, S.
    Nuss, E.
    Ohsugi, T.
    Ormes, J. F.
    Paneque, D.
    Perkins, J. S.
    Piron, F.
    Pivato, G.
    Rainò, S.
    Razzano, M.
    Reimer, A.
    Reimer, O.
    Ritz, S.
    Schaal, M.
    Sgrò, C.
    Siskind, E. J.
    Spinelli, P.
    Takahashi, H.
    Tibaldo, L.
    Tinivella, M.
    Troja, E.
    Vianello, G.
    Werner, M.
    Wood, M.
    Collaboration, Fermi LAT
    Deep Broadband Observations of the Distant Gamma-Ray Blazar PKS 1424+2402014In: Astrophysical Journal Letters, ISSN 2041-8205, E-ISSN 2041-8213, Vol. 785, no 1, article id L16Article in journal (Refereed)
    Abstract [en]

    We present deep VERITAS observations of the blazar PKS 1424+240, along with contemporaneous Fermi Large Area Telescope, Swift X-ray Telescope, and Swift UV Optical Telescope data between 2009 February 19 and 2013 June 8. This blazar resides at a redshift of z ≥ 0.6035, displaying a significantly attenuated gamma-ray flux above 100 GeV due to photon absorption via pair-production with the extragalactic background light. We present more than 100 hr of VERITAS observations over three years, a multiwavelength light curve, and the contemporaneous spectral energy distributions. The source shows a higher flux of (2.1 ± 0.3) × 10–7 photons m–2 s–1 above 120 GeV in 2009 and 2011 as compared to the flux measured in 2013, corresponding to (1.02 ± 0.08) × 10–7 photons m–2 s–1 above 120 GeV. The measured differential very high energy (VHE; E ≥ 100 GeV) spectral indices are Γ = 3.8 ± 0.3, 4.3 ± 0.6 and 4.5 ± 0.2 in 2009, 2011, and 2013, respectively. No significant spectral change across the observation epochs is detected. We find no evidence for variability at gamma-ray opacities of greater than τ = 2, where it is postulated that any variability would be small and occur on timescales longer than a year if hadronic cosmic-ray interactions with extragalactic photon fields provide a secondary VHE photon flux. The data cannot rule out such variability due to low statistics.

  • 275. Archambault, S.
    et al.
    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.
    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.
    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.
    Otte, A. N.
    Pandel, D.
    Park, N.
    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.
    Sheidaei, F.
    Smith, A. W.
    Staszak, D.
    Telezhinsky, I.
    Theiling, M.
    Tucci, J. V.
    Tyler, J.
    Varlotta, A.
    Vincent, S.
    Wakely, S. P.
    Weekes, T. C.
    Weinstein, A.
    Williams, D. A.
    Zitzer, B.
    Collaboration, V E R I T A S
    McCollough, M. L.
    Astrophysical Observatory, S.
    VERITAS Observations of the Microquasar Cygnus X-32013In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 779, no 2, article id 150Article in journal (Refereed)
    Abstract [en]

    We report results from TeV gamma-ray observations of the microquasar Cygnus X-3. The observations were made with the Very Energetic Radiation Imaging Telescope Array System (VERITAS) over a time period from 2007 June 11 to 2011 November 28. VERITAS is most sensitive to gamma rays at energies between 85 GeV and 30 TeV. The effective exposure time amounts to a total of about 44 hr, with the observations covering six distinct radio/X-ray states of the object. No significant TeV gamma-ray emission was detected in any of the states, nor with all observations combined. The lack of a positive signal, especially in the states where GeV gamma rays were detected, places constraints on TeV gamma-ray production in Cygnus X-3. We discuss the implications of the results.

  • 276.
    Aref’eva, I. Ya.
    et al.
    Russian Academy of Sciences, Russia.
    Djordjevic, G. S.
    University of Niš, Serbia.
    Khrennikov, Andrei
    Linnaeus University, Faculty of Technology, Department of Mathematics.
    Kozyrev, S. V.
    Russian Academy of Sciences, Russia.
    Rakic, Z.
    University of Belgrade, Serbia.
    Volovich, I. V.
    Russian Academy of Sciences, Russia.
    p-Adic mathematical physics and B. Dragovich research2017In: P-Adic Numbers, Ultrametric Analysis, and Applications, ISSN 2070-0466, E-ISSN 2070-0474, Vol. 9, no 1, p. 82-85Article in journal (Refereed)
    Abstract [en]

    We present a brief review of some parts of p-adic mathematical physics related to the scientific work of Branko Dragovich on the occasion of his 70th birthday.

  • 277.
    Argyropoulou, Eftychia
    et al.
    National and Kapodistrian University of Athens, Greece.
    Ioannidis, Andreas
    Linnaeus University, Faculty of Technology, Department of Physics and Electrical Engineering.
    The eigenvalue problem for a bianisotropic cavity2013In: PIERS proceedings 2013: Progress in Electromagnetics Research Symposium, Electromagnetics Acad , 2013, p. 858-862Conference paper (Refereed)
    Abstract [en]

    We discuss the eigenvalue problem for a perfectly conducting bianisotropic cavity. We formulate the corresponding mathematical problem and we give a characterization of the eigenelements (non-zero eigenfrequencies and modes) via a perturbation argument involving the eigenelements of the hollow cavity.

  • 278.
    Arias, M.
    et al.
    Univ Amsterdam, Netherlands.
    Vink, J.
    Univ Amsterdam, Netherlands;SRON Netherlands Inst Space Res, Netherlands.
    de Gasperin, F.
    Leiden Univ, Netherlands;Netherlands Inst Radio Astron, Netherlands.
    Salas, P.
    Leiden Univ, Netherlands.
    Oonk, J. B. R.
    Leiden Univ, Netherlands;Netherlands Inst Radio Astron, Netherlands.
    van Weeren, R. J.
    Leiden Univ, Netherlands.
    van Amesfoort, A. S.
    Netherlands Inst Radio Astron, Netherlands.
    Anderson, J.
    Helmholtz Zentrum Potsdam, Germany.
    Beck, R.
    Max Planck Inst Radio Astron, Germany.
    Bell, M. E.
    Univ Technol Sydney, Australia.
    Bentum, M. J.
    Netherlands Inst Radio Astron, Netherlands;Eindhoven Univ Technol, Netherlands.
    Best, P.
    Univ Edinburgh, UK.
    Blaauw, R.
    Netherlands Inst Radio Astron, Netherlands.
    Breitling, F.
    Leibniz Inst Astrophys Potsdam AIP, Germany.
    Broderick, J. W.
    Netherlands Inst Radio Astron, Netherlands.
    Brouw, W. N.
    Netherlands Inst Radio Astron, Netherlands;Kapteyn Astron Inst, Netherlands.
    Brueggen, M.
    Univ Hamburg, Germany.
    Butcher, H. R.
    Australian Natl Univ, Australia.
    Ciardi, B.
    Max Planck Inst Astrophys, Germany.
    de Geus, E.
    Netherlands Inst Radio Astron, Netherlands;SmarterVision BV, Netherlands.
    Deller, A.
    Netherlands Inst Radio Astron, Netherlands;Swinburne Univ Technol, Australia.
    van Dijk, P. C. G.
    Netherlands Inst Radio Astron, Netherlands.
    Duscha, S.
    Netherlands Inst Radio Astron, Netherlands.
    Eisloeffel, J.
    Thuringer Landessternwarte, Germany.
    Garrett, M. A.
    Leiden Univ, Netherlands;Univ Manchester, UK.
    Griessmeier, J. M.
    Univ Orleans, France.
    Gunst, A. W.
    Netherlands Inst Radio Astron, Netherlands.
    van Haarlem, M. P.
    Netherlands Inst Radio Astron, Netherlands.
    Heald, G.
    Netherlands Inst Radio Astron, Netherlands;Kapteyn Astron Inst, POB 800, NL-9700 AV Groningen, Netherlands.;CSIRO Astron & Space Sci, Australia.
    Hessels, J.
    Univ Amsterdam, Netherlands;Netherlands Inst Radio Astron, Netherlands.
    Horandel, J.
    Radboud Univ Nijmegen, Netherlands.
    Holties, H. A.
    Netherlands Inst Radio Astron, Netherlands.
    van der Horst, A. J.
    George Washington Univ, USA.
    Iacobelli, M.
    Netherlands Inst Radio Astron, Netherlands.
    Juette, E.
    Ruhr Univ Bochum, Germany.
    Krankowski, A.
    Univ Warmia & Mazury, Poland.
    van Leeuwen, J.
    Univ Amsterdam, Netherlands;Netherlands Inst Radio Astron, Netherlands.
    Mann, G.
    Leibniz Inst Astrophys Potsdam AIP, Germany.
    McKay-Bukowski, D.
    Univ Tromsö, Norway;STFC Rutherford Appleton Lab, UK.
    McKean, J. P.
    Netherlands Inst Radio Astron, Netherlands;Kapteyn Astron Inst, Netherlands.
    Mulder, H.
    Netherlands Inst Radio Astron, Netherlands.
    Nelles, A.
    Univ Calif Irvine, USA.
    Orru, E.
    Netherlands Inst Radio Astron, Netherlands.
    Paas, H.
    Univ Groningen, Netherlands.
    Pandey-Pommier, M.
    Observ Lyon, France.
    Pandey, V. N.
    Netherlands Inst Radio Astron, Netherlands;Kapteyn Astron Inst, Netherlands.
    Pekal, R.
    Poznan Supercomp & Networking Ctr PCSS, Poland.
    Pizzo, R.
    Netherlands Inst Radio Astron, Netherlands.
    Polatidis, A. G.
    Netherlands Inst Radio Astron, Netherlands.
    Reich, W.
    Max Planck Inst Radio Astron, Germany.
    Rottgering, H. J. A.
    Leiden Univ, Netherlands.
    Rothkaehl, H.
    Space Res Ctr PAS, Poland.
    Schwarz, D. J.
    Univ Bielefeld, Germany.
    Smirnov, O.
    Rhodes Univ, South Africa;SKA South Africa, South Africa.
    Soida, M.
    Jagiellonian Univ, Poland.
    Steinmetz, M.
    Leibniz Inst Astrophys Potsdam AIP, Germany.
    Tagger, M.
    Univ Orleans, France.
    Thoudam, Satyendra
    Linnaeus University, Faculty of Technology, Department of Physics and Electrical Engineering.
    Toribio, M. C.
    Leiden Univ,Netherlands;Netherlands Inst Radio Astron, Netherlands.
    Vocks, C.
    Leibniz Inst Astrophys Potsdam AIP, Germany.
    van der Wiel, M. H. D.
    Netherlands Inst Radio Astron, Netherlands.
    Wijers, R. A. M. J.
    Univ Amsterdam, Netherlands.
    Wucknitz, O.
    Max Planck Inst Radio Astron, Germany.
    Zarka, P.
    Observ Paris, France;Observ Paris, France.
    Zucca, P.
    Netherlands Inst Radio Astron, Netherlands.
    Low-frequency radio absorption in Cassiopeia A2018In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 612, article id A110Article in journal (Refereed)
    Abstract [en]

    Context. Cassiopeia A is one of the best-studied supernova remnants. Its bright radio and X-ray emission is due to shocked ejecta. Cas A is rather unique in that the unshocked ejecta can also be studied: through emission in the infrared, the radio-active decay of Ti-44, and the low-frequency free-free absorption caused by cold ionised gas, which is the topic of this paper. Aims. Free-free absorption processes are affected by the mass, geometry, temperature, and ionisation conditions in the absorbing gas. Observations at the lowest radio frequencies can constrain a combination of these properties. Methods. We used Low Frequency Array (LOFAR) Low Band Antenna observations at 30-77 MHz and Very Large Array (VLA) L-band observations at 1-2 GHz to fit for internal absorption as parametrised by the emission measure. We simultaneously fit multiple UV-matched images with a common resolution of 17 '' (this corresponds to 0.25 pc for a source at the distance of Cas A). The ample frequency coverage allows us separate the relative contributions from the absorbing gas, the unabsorbed front of the shell, and the absorbed back of the shell to the emission spectrum. We explored the effects that a temperature lower than the similar to 100-500 K proposed from infrared observations and a high degree of clumping can have on the derived physical properties of the unshocked material, such as its mass and density. We also compiled integrated radio flux density measurements, fit for the absorption processes that occur in the radio band, and considered their effect on the secular decline of the source. Results. We find a mass in the unshocked ejecta of M = 2.95 +/- 0.48 M-circle dot for an assumed gas temperature of T = 100 K. This estimate is reduced for colder gas temperatures and, most significantly, if the ejecta are clumped. We measure the reverse shock to have a radius of 114 '' +/- 6 '' and be centred at 23:23:26, +58:48:54 (J2000). We also find that a decrease in the amount of mass in the unshocked ejecta (as more and more material meets the reverse shock and heats up) cannot account for the observed low-frequency behaviour of the secular decline rate. Conclusions. To reconcile our low-frequency absorption measurements with models that reproduce much of the observed behaviour in Cas A and predict little mass in the unshocked ejecta, the ejecta need to be very clumped or the temperature in the cold gas needs to be low (similar to 10 K). Both of these options are plausible and can together contribute to the high absorption value that we find.

  • 279. Arlen, T.
    et al.
    Aune, T.
    Beilicke, M.
    Benbow, W.
    Bouvier, A.
    Buckley, J. H.
    Bugaev, V.
    Byrum, K.
    Cannon, A.
    Cesarini, A.
    Ciupik, L.
    Collins-Hughes, E.
    Connolly, M. P.
    Cui, W.
    Dickherber, R.
    Dumm, J.
    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.
    Holder, J.
    Huan, H.
    Hughes, G.
    Humensky, T. B.
    Imran, A.
    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.
    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.
    Ruppel, J.
    Saxon, D. B.
    Schroedter, M.
    Sembroski, G. H.
    Skole, C.
    Smith, A. W.
    Telezhinsky, I.
    Tesić, G.
    Theiling, M.
    Thibadeau, S.
    Tsurusaki, K.
    Varlotta, A.
    Vivier, M.
    Wakely, S. P.
    Ward, J. E.
    Weinstein, A.
    Welsing, R.
    Williams, D. A.
    Zitzer, B.
    Pfrommer, C.
    Pinzke, A.
    Constraints on Cosmic Rays, Magnetic Fields, and Dark Matter from Gamma-Ray Observations of the Coma Cluster of Galaxies with VERITAS and Fermi2012In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 757, no 2, article id 123Article 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.

  • 280. Arlen, T.
    et al.
    Aune, T.
    Beilicke, M.
    Benbow, W.
    Bouvier, A.
    Buckley, J. H.
    Bugaev, V.
    Cesarini, A.
    Ciupik, L.
    Connolly, M. P.
    Cui, W.
    Dickherber, R.
    Dumm, J.
    Errando, M.
    Falcone, A.
    Federici, S.
    Feng, Q.
    Finley, J. P.
    Finnegan, G.
    Fortson, L.
    Furniss, A.
    Galante, N.
    Gall, D.
    Griffin, S.
    Grube, J.
    Gyuk, G.
    Hanna, D.
    Holder, J.
    Humensky, T. B.
    Kaaret, P.
    Karlsson, N.
    Kertzman, M.
    Khassen, Y.
    Kieda, D.
    Krawczynski, H.
    Krennrich, F.
    Maier, G.
    Moriarty, P.
    Mukherjee, R.
    Nelson, T.
    O’Faoláin de Bhróithe, A.
    Ong, R. A.
    Orr, M.
    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.
    Schroedter, M.
    Sembroski, G. H.
    Staszak, D.
    Telezhinsky, I.
    Te\v sić, G.
    Theiling, M.
    Tsurusaki, K.
    Varlotta, A.
    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
    Jorstad, S. G.
    MacDonald, N. R.
    Marscher, A. P.
    Smith, P. S.
    Walker, R. C.
    Hovatta, T.
    Richards, J.
    Max-Moerbeck, W.
    Readhead, A.
    Lister, M. L.
    Kovalev, Y. Y.
    Pushkarev, A. B.
    Gurwell, M. A.
    Lähteenmäki, A.
    Nieppola, E.
    Tornikoski, M.
    Järvelä, E.
    Rapid TeV Gamma-Ray Flaring of BL Lacertae2013In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 762, no 2, article id 92Article in journal (Refereed)
    Abstract [en]

    We report on the detection of a very rapid TeV gamma-ray flare from BL Lacertae on 2011 June 28 with the Very Energetic Radiation Imaging Telescope Array System (VERITAS). The flaring activity was observed during a 34.6 minute exposure, when the integral flux above 200 GeV reached (3.4 ± 0.6) × 10–6 photons m–2 s–1, roughly 125% of the Crab Nebula flux measured by VERITAS. The light curve indicates that the observations missed the rising phase of the flare but covered a significant portion of the decaying phase. The exponential decay time was determined to be 13 ± 4 minutes, making it one of the most rapid gamma-ray flares seen from a TeV blazar. The gamma-ray spectrum of BL Lacertae during the flare was soft, with a photon index of 3.6 ± 0.4, which is in agreement with the measurement made previously by MAGIC in a lower flaring state. Contemporaneous radio observations of the source with the Very Long Baseline Array revealed the emergence of a new, superluminal component from the core around the time of the TeV gamma-ray flare, accompanied by changes in the optical polarization angle. Changes in flux also appear to have occurred at optical, UV, and GeV gamma-ray wavelengths at the time of the flare, although they are difficult to quantify precisely due to sparse coverage. A strong flare was seen at radio wavelengths roughly four months later, which might be related to the gamma-ray flaring activities. We discuss the implications of these multiwavelength results.

  • 281. Armijo, V.
    et al.
    Black, K.
    Bolton, R. D.
    Carius, Staffan
    Department of Radiation Sciences, Uppsala University.
    Cooper, M. D.
    Espinoza, C.
    Hart, G.
    Hogan, G. E.
    Ludwig, G.
    Mischke, R. E.
    Piilonen, L.
    Stanislaus, S.
    Sandoval, J.
    Whitehouse, D. A.
    Wilkinson, C.
    Jui, C. C. H.
    A fast MWPC with cathode strips and utilizing CF4-isobutane1991In: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, ISSN 0168-9002, E-ISSN 1872-9576, Vol. 303, no 2, p. 298-308Article in journal (Refereed)
    Abstract [en]

    A planar wire chamber has been developed at LAMPF as a prototype for wire chambers of cylindrical configuration for electron detection in the MEGA experiment. Results form tests with the planar chamber have been used to set the geometrical parameters and predict the performance characteristics of the cylindrical chambers. The behavior of the planar chamber with CF4-isobutane gas demonstrates that 15 μm wire of 1 mm pitch is practical, that lifetimes greater than 0.045 C/cm are achievable and that gate widths of 25 ns are possible. © 1991.

  • 282.
    Arrabito, L.
    et al.
    Univ Montpellier 2, France.
    Bregeon, J.
    Univ Montpellier 2, France.
    Haupt, Andreas
    Linnaeus University, Faculty of Technology, Department of Physics and Electrical Engineering. DESY, Germany.
    Graciani Diaz, R.
    Univ Barcelona, Spain.
    Stagni, F.
    CERN, Switzerland.
    Tsaregorodtsev, A.
    CNRS, France.
    Prototype of a production system for Cherenkov Telescope Array with DIRAC2015In: 21ST INTERNATIONAL CONFERENCE ON COMPUTING IN HIGH ENERGY AND NUCLEAR PHYSICS (CHEP2015), PARTS 1-9, 2015, p. Article ID: 032001-, article id 032001Conference paper (Refereed)
    Abstract [en]

    The Cherenkov Telescope Array (CTA) an array of many tens of Imaging Atmospheric Cherenkov Telescopes deployed on an unprecedented scale is the next generation instrument in the field of very high energy gamma-ray astronomy. CTA will operate as an open observatory providing data products to the scientific community. An average data stream of about 10 GB/s for about 1000 hours of observation per year, thus producing several PB/year, is expected. Large CPU time is required for data-processing as well for massive Monte Carlo simulations needed for detector calibration purposes. The current CTA computing model is based on a distributed infrastructure for the archive and the data off-line processing. In order to manage the off-line data-processing in a distributed environment, CTA has evaluated the DIRAC (Distributed Infrastructure with Remote Agent Control) system, which is a general framework for the management of tasks over distributed heterogeneous computing environments. In particular, a production system prototype has been developed, based on the two main DIRAC components, i.e. the Workload Management and Data Management Systems. After three years of successful exploitation of this prototype, for simulations and analysis, we proved that DIRAC provides suitable functionalities needed for the CTA data processing. Based on these results, the CTA development plan aims to achieve an operational production system, based on the DIRAC Workload Management System, to be ready for the start of CTA operation phase in 2017-2018. One more important challenge consists of the development of a fully automatized execution of the CTA workflows. For this purpose, we have identified a third DIRAC component, the so-called Transformation System, which offers very interesting functionalities to achieve this automatisation. The Transformation System is a 'data driven' system, allowing to automatically trigger data-processing and data management operations according to pre-defined scenarios. In this paper, we present a brief summary of the DIRAC evaluation done so far, as well as the future developments planned for the CTA production system. In particular, we will focus on the developments of CTA automatic workflows, based on the Transformation System. As a result, we also propose some design optimizations of the Transformation System, in order to fully support the most complex workflows, envisaged in the CTA processing.

  • 283.
    Asano, Masanari
    et al.
    Tokyo University of Science.
    Basieva, Irina
    Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
    Khrennikov, Andrei
    Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
    Ohya, Masanori
    Tokyo University of Science.
    Tanaka, Yoshiharu
    Tokyo University of Science.
    Quantum-like Dynamics of Decision-making in Prisoner's Dilemma Game2012In: AIP Conference Proceedings, ISSN 0094-243X, E-ISSN 1551-7616, Vol. 1424, p. 453-457Article in journal (Refereed)
    Abstract [en]

    In cognitive psychology, some experiments of games were reported [1, 2, 3, 4], and these demonstrated that real players did not use the "rational strategy" provided by classical game theory. To discuss probabilities of such "irrational choice", recently, we proposed a decision-making model which is based on the formalism of quantum mechanics [5, 6, 7, 8]. In this paper, we briefly explain the above model and calculate the probability of irrational choice in several prisoner's dilemma (PD) games.

  • 284. Asano, Masanari
    et al.
    Basieva, Irina
    Khrennikov, Andrei
    Linnaeus University, Faculty of Technology, Department of Mathematics.
    Ohya, Masanori
    Tanaka, Yoshiharu
    Yamato, Ichiro
    Quantum Information Biology2016In: Contextuality from Quantum Physics to Psychology / [ed] Ehtibar Dzhafarov, Scott Jordan, Ru Zhang, Victor Cervantes, World Scientific, 2016, p. 399-413Chapter in book (Refereed)
    Abstract [en]

    This chapter reviews quantum(-like) information biology (QIB). Here biology is treated widely as even covering cognition and its derivatives: psychology and decision making, sociology, and behavioral economics and finances. QIB provides an integrative description of information processing by bio-systems at all scales of life: from proteins and cells to cognition, ecological and social systems. Mathematically QIB is based on the theory of adaptive quantum systems (which covers also open quantum systems). Ideologically QIB is based on the quantum-like (QL) paradigm: complex bio-systems process information in accordance with the laws of quantum information and probability. This paradigm is supported by plenty of statistical bio-data collected at all bio-scales. QIB reflects the two fundamental principles: a) adaptivity; and, b) openness (bio-systems are fundamentally open). In addition, quantum adaptive dynamics provides the most generally possible mathematical representation of these principles.

  • 285.
    Asano, Masanari
    et al.
    Tokuyama Coll Technol, Japan.
    Basieva, Irina
    Linnaeus University, Faculty of Technology, Department of Mathematics.
    Khrennikov, Andrei
    Linnaeus University, Faculty of Technology, Department of Mathematics.
    Ohya, Masanori
    Tokyo Univ Sci, Japan.
    Tanaka, Yoshiharu
    Tokyo Univ Sci, Japan.
    Yamato, Ichiro
    Tokyo Univ Sci, Japan.
    Quantum Information Biology: From Information Interpretation of Quantum Mechanics to Applications in Molecular Biology and Cognitive Psychology2015In: Foundations of physics, ISSN 0015-9018, E-ISSN 1572-9516, Vol. 45, no 10, p. 1362-1378Article in journal (Refereed)
    Abstract [en]

    We discuss foundational issues of quantum information biology (QIB)-one of the most successful applications of the quantum formalism outside of physics. QIB provides a multi-scale model of information processing in bio-systems: from proteins and cells to cognitive and social systems. This theory has to be sharply distinguished from "traditional quantum biophysics". The latter is about quantum bio-physical processes, e.g., in cells or brains. QIB models the dynamics of information states of bio-systems. We argue that the information interpretation of quantum mechanics (its various forms were elaborated by Zeilinger and Brukner, Fuchs and Mermin, and D' Ariano) is the most natural interpretation of QIB. Biologically QIB is based on two principles: (a) adaptivity; (b) openness (bio-systems are fundamentally open). These principles are mathematically represented in the framework of a novel formalism- quantum adaptive dynamics which, in particular, contains the standard theory of open quantum systems.

  • 286.
    Asano, Masanari
    et al.
    Tokyo University of Science.
    Basieva, Irina
    Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
    Khrennikov, Andrei
    Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
    Ohya, Masanori
    Tokyo University of Science.
    Tanaka, Yoshiharu
    Tokyo University of Science.
    Yamato, Ichiro
    Tokyo University of Science.
    Quantum-like model of glucose effect on Escherichia coli growth2012In: AIP Conference Proceedings, ISSN 0094-243X, E-ISSN 1551-7616, Vol. 1424, p. 507-512Article in journal (Refereed)
    Abstract [en]

    Recently, we proposed a new method to compute probabilities which do not satisfy basic law in classical probability theory. In this note, we analyze glucose effect in Escherichia coli's growth with the method, and we show an invariant quantity which Escherichia coli has.

  • 287.
    Asano, Masanari
    et al.
    Tokuyama College of Technology Gakuendai, Japan.
    Hashimoto, Takahisa
    Tokuyama College of Technology Gakuendai, Japan.
    Khrennikov, Andrei
    Linnaeus University, Faculty of Technology, Department of Mathematics.
    Ohya, Masanori
    Tokuyama College of Technology Gakuendai, Japan.
    Tanaka, Yoshiharu
    Tokuyama College of Technology Gakuendai, Japan.
    Adaptive Dynamics and Optical Illusion on Schröder’s Stair2014In: Quantum Interaction: 7th International Conference, QI 2013, Leicester, UK, July 25-27, 2013. Selected Papers / [ed] Harald Atmanspacher, Emmanuel Haven, Kirsty Kitto, Derek Raine, Springer, 2014, p. 191-200Conference paper (Refereed)
    Abstract [en]

    Recently, various examples of non-Kolmogorovness in contextual dependent phenomena have been reported. In this study, we introduce non-Kolmogorovness in the measurement of depth inversion for the figure of Schröder’s stair. Also we propose a model of the depth inversion, based on a non-Kolmogorovian probability theory which is called adaptive dynamics.

  • 288.
    Asano, Masanari
    et al.
    Tokuyama Coll Technol, Japan.
    Hashimoto, Takahisa
    Tokyo Univ Sci, Japan.
    Khrennikov, Andrei
    Linnaeus University, Faculty of Technology, Department of Mathematics.
    Ohya, Masanori
    Tokyo Univ Sci, Japan.
    Tanaka, Yoshiharu
    Tokyo Univ Sci, Japan.
    Violation of contextual generalization of the Leggett-Garg inequality for recognition of ambiguous figures2014In: Physica Scripta, ISSN 0031-8949, E-ISSN 1402-4896, Vol. T163, article id 014006Article in journal (Refereed)
    Abstract [en]

    We interpret the Leggett-Garg (LG) inequality as a kind of contextual probabilistic inequality in which one combines data collected in experiments performed for three different contexts. In the original version of the inequality, these contexts have a temporal nature and they are represented by three pairs of instances of time, (t(1), t(2)), (t(2), t(3)), (t(3), t(4)), where t(1) < t(2) < t(3). We generalize LG conditions of macroscopic realism and noninvasive measurability in a general contextual framework. Our formulation is performed in purely probabilistic terms: the existence of the context-independent joint probability distribution P and the possibility of reconstructing the experimentally found marginal (two-dimensional) probability distributions from P. We derive an analog of the LG inequality, 'contextual LG inequality', and use it as a test of 'quantum-likeness' of statistical data collected in a series of experiments on the recognition of ambiguous figures. In our experimental study, the figure under recognition is the Schroder stair, which is shown with rotations for different angles. Contexts are encoded by dynamics of rotations: clockwise, anticlockwise and random. Our data demonstrated violation of the contextual LG inequality for some combinations of the aforementioned contexts. Since in quantum theory and experiments with quantum physical systems, this inequality is violated, e.g. in the form of the original LG-inequality, our result can be interpreted as a sign that the quantum-like models can provide a more adequate description of the data generated in the process of recognition of ambiguous figures.

  • 289. Askebjer, P.
    et al.
    Barwick, S.
    Bergstrom, L.
    Bouchta, A.
    Carius, Staffan
    Uppsala University.
    Coulthard, A.
    Engel, K.
    Erlandsson, B.
    Goobar, A.
    Gray, L.
    Hallgren, A.
    Halzen, F.
    Hulth, P. O.
    Jacobsen, J.
    Johansson, S.
    Kandhadai, V.
    Liubarsky, I.
    Lowder, D.
    Miller, T.
    Mock, P. C.
    Morse, R.
    Porrata, R.
    Price, P. B.
    Richards, A.
    Rubinstein, H.
    Spang, J. C.
    Sun, Q.
    Tilav, S.
    Walck, C.
    Yodh, G.
    On the age vs depth and optical clarity of deep ice at South Pole1995In: Journal of Glaciology, ISSN 0022-1430, E-ISSN 1727-5652, Vol. 41, no 139, p. 445-454Article in journal (Refereed)
    Abstract [en]

    The first four strings of phototubes for the AMANDA high-energy neutrino observatory are now frozen in place at a depth of 800 to 1000 m in ice at the South Pole. During the 1995-96 season an additional six strings will be deployed at greater depths. Provided absorption, scattering, and refraction of visible light are sufficiently small, the trajectory of a muon into which a neutrino converts can be determined by using the array of phototubes to measure the arrival times of \v{C}erenkov light emitted by the muon. To help in deciding on the depth for implantation of the six new strings, we discuss models of age vs depth for South Pole ice, we estimate mean free paths for scattering from bubbles and dust as a function of depth, and we assess distortion of light paths due to refraction at crystal boundaries and interfaces between air-hydrate inclusions and normal ice. We conclude that the depth interval 1600 to 1800 m will be suitably transparent for the next six AMANDA strings and, moreover, that the interval 1600 to 2100 m will be suitably transparent for a future 1-km 3   observatory except possibly in a region a few tens of meters thick at a depth corresponding to a peak in the dust concentration at 60 kyr BP.

  • 290. Askebjer, P.
    et al.
    Barwick, S. W.
    Bay, R.
    Bergström, L.
    Bouchta, A.
    Carius, Staffan
    University of Uppsala.
    Dahlberg, E.
    Engel, K.
    Erlandsson, B.
    Goobar, A.
    Gray, L.
    Hallgren, A.
    Halzen, F.
    Heukenkamp, H.
    Hulth, P. O.
    Hundertmark, S.
    Jacobsen, J.
    Johansson, S.
    Kandhadai, V.
    Karle, A.
    Liubarsky, I.
    Lowder, D.
    Mikolajski, T.
    Miller, T. C.
    Mock, P.
    Morse, R.
    Nygren, D.
    Porrata, R.
    Price, P. B.
    Richards, A.
    Rubinstein, H.
    Schneider, E.
    Spiering, C.
    Streicher, O.
    Sun, Q.
    Thon, T.
    Tilav, S.
    Walck, C.
    Wiebusch, C.
    Wischnewski, R.
    Yodh, G.
    Belolaptikov, I. A.
    Bezrukov, L. B.
    Borisovets, B. A.
    Budnev, N. M.
    Chensky, A. G.
    Danilchenko, I. A.
    Djilkibaev, Zh.-A.M.
    Dobrynin, V. I.
    Domogatsky, G. V.
    Doroshenko, A. A.
    Fialkovsky, S. V.
    Gaponenko, O. N.
    Garus, A. A.
    Gress, T. A.
    Ignat'ev, S. B.
    Klabukov, A. M.
    Klimov, A. I.
    Klimushin, S. I.
    Koshechkin, A. P.
    Kulepov, V. F.
    Kuzmichev, L. A.
    Lubsandorzhiev, B. K.
    Milenin, M. B.
    Mirgazov, R. R.
    Moroz, A. V.
    Moseiko, N. I.
    Nikiforov, S. A.
    Osipova, E. A.
    Pandel, D.
    Panfilov, A. I.
    Parfenov, Yu.V.
    Pavlov, A. A.
    Petukhov, D. P.
    Pocheikin, K. A.
    Pokhil, P. G.
    Pokolev, P. A.
    Rosanov, M. I.
    Rubzov, V.Yu.
    Sinegovsky, S. I.
    Sokalski, I. A.
    Spiering, Ch.
    Tarashansky, B. A.
    Status of the AMANDA and BAIKAL neutrino telescopes1997In: Nuclear physics B, Proceedings supplements, ISSN 0920-5632, E-ISSN 1873-3832, Vol. 52, no 3, p. 256-260Article in journal (Refereed)
  • 291. Askebjer, P.
    et al.
    Barwick, S. W.
    Bergström, L.
    Bouchta, A.
    Carius, Staffan
    Coulthard, A.
    Engel, K.
    Erlandsson, B.
    Goobar, A.
    Gray, L.
    Hallgren, A.
    Halzen, F.
    Hulth, P. O.
    Jacobsen, J.
    Johansson, S.
    Kandhadai, V.
    Liubarsky, I.
    Lowder, D.
    Miller, T.
    Mock, P. C.
    Morse, R.
    Porrata, R.
    Price, P. B.
    Richards, A.
    Rubinstein, H.
    Schneider, E.
    Sun, Q.
    Tilav, S.
    Walck, C.
    Yodh, G.
    Optical properties of the South Pole ice at depths between 0.8 and 1 kilometer1995In: Science, ISSN 0036-8075, E-ISSN 1095-9203, Vol. 267, no 5201, p. 1147-1150Article in journal (Refereed)
    Abstract [en]

    The optical properties of the ice at the geographical South Pole have been investigated at depths between 0.8 and 1 kilometer. The absorption and scattering lengths of visible light (∼515 nanometers) have been measured in situ with the use of the laser calibration setup of the Antarctic Muon and Neutrino Detector Array (AMANDA) neutrino detector. The ice is intrinsically extremely transparent. The measured absorption length is 59 ± 3 meters, comparable with the quality of the ultrapure water used in the Irvine-Michigan-Brookhaven and Kamiokande proton-decay and neutrino experiments and more than twice as long as the best value reported for laboratory ice. Because of a residual density of air bubbles at these depths, the trajectories of photons in the medium are randomized. If the bubbles are assumed to be smooth and spherical, the average distance between collisions at a depth of 1 kilometer is about 25 centimeters. The measured inverse scattering length on bubbles decreases linearly with increasing depth in the volume of ice investigated.

  • 292. Askebjer, P.
    et al.
    Barwick, S. W.
    Bergström, L.
    Bouchta, A.
    Carius, Staffan
    Uppsala University.
    Coulthard, A.
    Engel, K.
    Erlandsson, B.
    Goobar, A.
    Gray, L.
    Hallgren, A.
    Halzen, F.
    Hulth, P. O.
    Jacobsen, J.
    Johansson, S.
    Kandhadai, V.
    Liubarsky, I.
    Lowder, D.
    Miller, T.
    Mock, P.
    Morse, R.
    Porrata, R.
    Price, P. B.
    Richards, A.
    Rubinstein, H.
    Schneider, E.
    Sun, Q.
    Tilav, S.
    Walck, C.
    Yodh, G.
    AMANDA: status report from the 1993-94 campaign and optical properties of the South Pole ice1995In: Nuclear physics B, Proceedings supplements, ISSN 0920-5632, E-ISSN 1873-3832, Vol. 38, no 1-3, p. 287-292Article in journal (Refereed)
    Abstract [en]

    We report the first results of the AMANDA detector. During the antarctic summer 1993-94 four strings were deployed between 0.8 an 1 km depth, each equipped with 20 photomultiplier tubes (PMTs). A laser source was used to investigate the optical properties of the ice in situ. We find that the ice is intrinsically extremely transparent. The measured absorption length is 59 ± 3 m, i.e. comparable with the quality of the ultra-pure water used in the IMB and Kamiokande proton-decay and neutrino experiments [1,2] and more than two times longer than the best value reported for laboratory ice [3]. Due to a residual density of air bubbles at these depths, the motion of photons in the medium is randomized. For spherical, smooth bubbles we find that, at 1 km depth, the average distance between collisions is about 25 cm. The measured inverse scattering length on bubbles decreases linearly with increasing depth in the volume of ice investigated. © 1995 Elsevier Science B.V. All rights reserved.

  • 293. Askebjer, P.
    et al.
    Barwick, S. W.
    Bergström, L.
    Bouchta, A.
    Carius, Staffan
    Department of Radiation Sciences, Uppsala University.
    Dalberg, E.
    Erlandsson, B.
    Goobar, A.
    Gray, L.
    Hallgren, A.
    Halzen, F.
    Heukenkamp, H.
    Hulth, P. O.
    Hundertmark, S.
    Jacobsen, J.
    Kandhadai, V.
    Karle, A.
    Liubarsky, I.
    Lowder, D.
    Miller, T.
    Mock, P.
    Morse, R.
    Porrata, R.
    Price, P. B.
    Richards, A.
    Rubinstein, H.
    Schneider, E.
    Spiering, Ch.
    Streicher, O.
    Sun, Q.
    Thon, Th.
    Tilav, S.
    Wischnewski, R.
    Walck, C.
    Yodh, G.
    UV and optical light transmission properties in deep ice at the South Pole1997In: Geophysical Research Letters, ISSN 0094-8276, E-ISSN 1944-8007, Vol. 24, no 11, p. 1355-1358Article in journal (Refereed)
    Abstract [en]

    Both absorption and scattering of light at wavelengths 410 to 610 nanometers were measured in the South Pole ice at depths 0.8 to 1 kilometer with the laser calibration system of the Antarctic Muon And Neutrino Detector Array (AMANDA). At the shortest wavelengths the absorption lengths exceeded 200 meters - an order of magnitude longer than has been reported for laboratory ice. The absorption shows a strong wavelength dependence while the scattering length is found to be independent of the wavelength, consistent with the hypothesis of a residual density of air bubbles in the ice. The observed linear decrease of the inverse scattering length with depth is compatible with an earlier measurement by the AMANDA collaboration (at ∼515 nanometers).

  • 294. Askebjer, P.
    et al.
    Berwick, S. W.
    Bergström, L.
    Bouchta, A.
    Carius, Staffan
    Department of Radiation Sciences, Uppsala University.
    Dalberg, E.
    Engel, K.
    Erlandsson, B.
    Goobar, A.
    Gray, L.
    Hallgren, A.
    Halzen, F.
    Heukenkamp, H.
    Hulth, P. O.
    Hundertmark, S.
    Jacobsen, J.
    Karle, A.
    Kandhadai, V.
    Liubarsky, I.
    Lowder, D.
    Miller, T.
    Mock, P.
    Morse, R. M.
    Porrata, R.
    Price, P. B.
    Richards, A.
    Rubinstein, H.
    Schneider, E.
    Spiering, C.
    Streicher, O.
    Sun, Q.
    Thon, T.
    Tilav, S.
    Wischnewski, R.
    Walck, C.
    Yodh, G. B.
    Optical properties of deep ice at the South Pole: Absorption1997In: Applied Optics, ISSN 0003-6935, E-ISSN 1539-4522, Vol. 36, no 18, p. 4168-4180Article in journal (Refereed)
    Abstract [en]

    We discuss recent measurements of the wavelength-dependent absorption coefficients in deep South Pole ice. The method uses transit-time distributions of pulses from a variable-frequency laser sent between emitters and receivers embedded in the ice. At depths of 800-1000 m scattering is dominated by residual air bubbles, whereas absorption occurs both in ice itself and in insoluble impurities. The absorption coefficient increases approximately exponentially with wavelength in the measured interval 410-610 nm. At the shortest wavelength our value is approximately a factor 20 below previous values obtained for laboratory ice and lake ice; with increasing wavelength the discrepancy with previous measurements decreases. At ∼415 to ∼500 nm the experimental uncertainties are small enough for us to resolve an extrinsic contribution to absorption in ice: submicrometer dust particles contribute by an amount that increases with depth and corresponds well with the expected increase seen near the Last Glacial Maximum in Vostok and Dome C ice cores. The laser pulse method allows remote mapping of gross structure in dust concentration as a function of depth in glacial ice.

  • 295.
    Asplund, Andreas
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Kontaktlinsens hanteringsfärg och behovet av skydd för det kortvågiga synliga ljuset2008Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpStudent thesis
    Abstract [sv]

    Kontaktlinser har idag oftast en hanteringsfärg, en färg för underlättande av hantering. Denna färg är i de flesta fall blå. Det kortvågiga blåa ljuset har visats kunna ge skador på ögats näthinna trots att det är inom det synliga spektrumet till skillnad från ultraviolett ljus. Inom kataraktkirurgin hanteras detta blåa ljus genom att en blåljus-filtrerande lins används. Kontaktlinsens blå hanteringsfärg har i denna studie utretts ur ett skyddsperspektiv för det kortvågiga blåa ljuset.

    Metod: Kontaktlinstillverkare blev tillfrågade om faktorer som prioriterats vid val av den blåa hanteringsfärgen. Kontaktlinser med olika hanteringsfärg mättes upp i en spektrograf för att undersöka skillnad i transmission av blått ljus.

    Resultat: Den blåa hanteringsfärgen hade främst valts av hanteringspraktiska och estetiska skäl, mer än av optiska och synhälsoskäl. Kontaktlinser med gul hanteringsfärg visades ge betydligt mer absorption av kortvågigt blått ljus än en kontaktlins med blå hanteringsfärg.

    Slutsats: För att skydda ögonen mot kortvågigt blått ljus, som har skadligt verkan på näthinnan, är en gul hanteringsfärg mer effektiv än en blå. Även de låga grader av färg som hanteringsfärgen innebär kan ge stor skillnad i absorption av ett visst område, om färg väljs därefter.

    2008:O5

  • 296. Atwood, W. B.
    et al.
    Abdo, A. A.
    Ackermann, M.
    Althouse, W.
    Anderson, B.
    Axelsson, M.
    Baldini, L.
    Ballet, J.
    Band, D. L.
    Barbiellini, G.
    Bartelt, J.
    Bastieri, D.
    Baughman, B. M.
    Bechtol, K.
    Bederede, D.
    Bellardi, F.
    Bellazzini, R.
    Berenji, B.
    Bignami, G. F.
    Bisello, D.
    Bissaldi, E.
    Blandford, R. D.
    Bloom, E. D.
    Bogart, J. R.
    Bonamente, E.
    Bonnell, J.
    Borgland, A. W.
    Bouvier, A.
    Bregeon, J.
    Brez, A.
    Brigida, M.
    Bruel, P.
    Burnett, T. H.
    Busetto, G.
    Caliandro, G. A.
    Cameron, R. A.
    Caraveo, P. A.
    Carius, Staffan
    University of Kalmar, Department of Technology.
    Carlson, P.
    Casandjian, J. M.
    Cavazzuti, E.
    Ceccanti, M.
    Cecchi, C.
    Charles, E.
    Chekhtman, A.
    Cheung, C. C.
    Chiang, J.
    Chipaux, R.
    Cillis, A. N.
    Ciprini, S.
    Claus, R.
    Cohen-Tanugi, J.
    Condamoor, S.
    Conrad, J.
    Corbet, R.
    Corucci, L.
    Costamante, L.
    Cutini, S.
    Davis, D. S.
    Decotigny, D.
    DeKlotz, M.
    Dermer, C. D.
    De Angelis, A.
    Digel, S. W.
    Silva, Edce
    Drell, P. S.
    Dubois, R.
    Dumora, D.
    Edmonds, Y.
    Fabiani, D.
    Farnier, C.
    Favuzzi, C.
    Flath, D. L.
    Fleury, P.
    Focke, W. B.
    Funk, S.
    Fusco, P.
    Gargano, F.
    Gasparrini, D.
    Gehrels, N.
    Gentit, F. X.
    Germani, S.
    Giebels, B.
    Giglietto, N.
    Giommi, P.
    Giordano, F.
    Glanzman, T.
    Godfrey, G.
    Grenier, I. A.
    Grondin, M. H.
    Grove, J. E.
    Guillemot, L.
    Guiriec, S.
    Haller, G.
    Harding, A. K.
    Hart, P. A.
    Hays, E.
    Healey, S. E.
    Hirayama, M.
    Hjalmarsdotter, L.
    Horn, R.
    Hughes, R. E.
    Johannesson, G.
    Johansson, G.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Johnson, A. S.
    Johnson, R. P.
    Johnson, T. J.
    Johnson, W. N.
    Kamae, T.
    Katagiri, H.
    Kataoka, J.
    Kavelaars, A.
    Kawai, N.
    Kelly, H.
    Kerr, M.
    Klamra, W.
    Knodlseder, J.
    Kocian, M. L.
    Komin, N.
    Kuehn, F.
    Kuss, M.
    Landriu, D.
    Latronico, L.
    Lee, B.
    Lee, S. H.
    Lemoine-Goumard, M.
    Lionetto, A. M.
    Longo, F.
    Loparco, F.
    Lott, B.
    Lovellette, M. N.
    Lubrano, P.
    Madejski, G. M.
    Makeev, A.
    Marangelli, B.
    Massai, M. M.
    Mazziotta, M. N.
    McEnery, J. E.
    Menon, N.
    Meurer, C.
    Michelson, P. F.
    Minuti, M.
    Mirizzi, N.
    Mitthumsiri, W.
    Mizuno, T.
    Moiseev, A. A.
    Monte, C.
    Monzani, M. E.
    Moretti, E.
    Morselli, A.
    Moskalenko, I. V.
    Murgia, S.
    Nakamori, T.
    Nishino, S.
    Nolan, P. L.
    Norris, J. P.
    Nuss, E.
    Ohno, M.
    Ohsugi, T.
    Omodei, N.
    Orlando, E.
    Ormes, J. F.
    Paccagnella, A.
    Paneque, D.
    Panetta, J. H.
    Parent, D.
    Pearce, M.
    Pepe, M.
    Perazzo, A.
    Pesce-Rollins, M.
    Picozza, P.
    Pieri, L.
    Pinchera, M.
    Piron, F.
    Porter, T. A.
    Poupard, L.
    Raino, S.
    Rando, R.
    Rapposelli, E.
    Razzano, M.
    Reimer, A.
    Reimer, O.
    Reposeur, T.
    Reyes, L. C.
    Ritz, S.
    Rochester, L. S.
    Rodriguez, A. Y.
    Romani, R. W.
    Roth, M.
    Russell, J. J.
    Ryde, F.
    Sabatini, S.
    Sadrozinski, H. F. W.
    Sanchez, D.
    Sander, A.
    Sapozhnikov, L.
    Parkinson, P. M. S.
    Scargle, J. D.
    Schalk, T. L.
    Scolieri, G.
    Sgro, C.
    Share, G. H.
    Shaw, M.
    Shimokawabe, T.
    Shrader, C.
    Sierpowska-Bartosik, A.
    Siskind, E. J.
    Smith, D. A.
    Smith, P. D.
    Spandre, G.
    Spinelli, P.
    Starck, J. L.
    Stephens, T. E.
    Strickman, M. S.
    Strong, A. W.
    Suson, D. J.
    Tajima, H.
    Takahashi, H.
    Takahashi, T.
    Tanaka, T.
    Tenze, A.
    Tether, S.
    Thayer, J. B.
    Thayer, J. G.
    Thompson, D. J.
    Tibaldo, L.
    Tibolla, O.
    Torres, D. F.
    Tosti, G.
    Tramacere, A.
    Turri, M.
    Usher, T. L.
    Vilchez, N.
    Vitale, V.
    Wang, P.
    Watters, K.
    Winer, B. L.
    Wood, K. S.
    Ylinen, T.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Ziegler, M.
    THE LARGE AREA TELESCOPE ON THE FERMI GAMMA-RAY SPACE TELESCOPE MISSION2009In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 697, no 2, p. 1071-1102Article in journal (Refereed)
    Abstract [en]

    The Large Area Telescope (Fermi/LAT, hereafter LAT), the primary instrument on the Fermi Gamma-ray Space Telescope (Fermi) mission, is an imaging, wide field-of-view (FoV), high-energy gamma-ray telescope, covering the energy range from below 20 MeV to more than 300 GeV. The LAT was built by an international collaboration with contributions from space agencies, high-energy particle physics institutes, and universities in France, Italy, Japan, Sweden, and the United States. This paper describes the LAT, its preflight expected performance, and summarizes the key science objectives that will be addressed. On-orbit performance will be presented in detail in a subsequent paper. The LAT is a pair-conversion telescope with a precision tracker and calorimeter, each consisting of a 4 x 4 array of 16 modules, a segmented anticoincidence detector that covers the tracker array, and a programmable trigger and data acquisition system. Each tracker module has a vertical stack of 18 (x, y) tracking planes, including two layers (x and y) of single-sided silicon strip detectors and high-Z converter material (tungsten) per tray. Every calorimeter module has 96 CsI(Tl) crystals, arranged in an eight-layer hodoscopic configuration with a total depth of 8.6 radiation lengths, giving both longitudinal and transverse information about the energy deposition pattern. The calorimeter's depth and segmentation enable the high-energy reach of the LAT and contribute significantly to background rejection. The aspect ratio of the tracker (height/width) is 0.4, allowing a large FoV (2.4 sr) and ensuring that most pair-conversion showers initiated in the tracker will pass into the calorimeter for energy measurement. Data obtained with the LAT are intended to (1) permit rapid notification of high-energy gamma-ray bursts and transients and facilitate monitoring of variable sources, (2) yield an extensive catalog of several thousand high-energy sources obtained from an all-sky survey, (3) measure spectra from 20 MeV to more than 50 GeV for several hundred sources, (4) localize point sources to 0.3-2 arcmin, (5) map and obtain spectra of extended sources such as SNRs, molecular clouds, and nearby galaxies, (6) measure the diffuse isotropic gamma-ray background up to TeV energies, and (7) explore the discovery space for dark matter.

  • 297.
    Azimi Mousolou, Vahid
    Linnaeus University, Faculty of Technology, Department of Physics and Electrical Engineering.
    Quantum Holonomy for Many-Body Systems and Quantum Computation2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The research of this Ph. D. thesis is in the field of Quantum Computation and Quantum

    Information. A key problem in this field is the fragile nature of quantum states. This

    becomes increasingly acute when the number of quantum bits (qubits) grows in order to

    perform large quantum computations. It has been proposed that geometric (Berry) phases

    may be a useful tool to overcome this problem, because of the inherent robustness of such

    phases to random noise. In the thesis we investigate geometric phases and quantum

    holonomies (matrix-valued geometric phases) in many-body quantum systems, and elucidate

    the relationship between these phases and the quantum correlations present in the systems.

    An overall goal of the project is to assess the feasibility of using geometric phases and

    quantum holonomies to build robust quantum gates, and investigate their behavior when the

    size of a quantum system grows, thereby gaining insights into large-scale quantum

    computation.

    In a first project we study the Uhlmann holonomy of quantum states for hydrogen-like

    atoms. We try to get into a physical interpretation of this geometric concept by analyzing its

    relation with quantum correlations in the system, as well as by comparing it with different

    types of geometric phases such as the standard pure state geometric phase, Wilczek-Zee

    holonomy, Lévay geometric phase and mixed-state geometric phases. In a second project we

    establish a unifying connection between the geometric phase and the geometric measure of

    entanglement in a generic many-body system, which provides a universal approach to the

    study of quantum critical phenomena. This approach can be tested experimentally in an

    interferometry setup, where the geometric measure of entanglement yields the visibility of

    the interference fringes, whereas the geometric phase describes the phase shifts. In a third

    project we propose a scheme to implement universal non-adiabatic holonomic quantum

    gates, which can be realized in novel nano-engineered systems such as quantum dots,

    molecular magnets, optical lattices and topological insulators. In a fourth project we propose

    an experimentally feasible approach based on “orange slice” shaped paths to realize non-

    Abelian geometric phases, which can be used particularly for geometric manipulation of

    qubits. Finally, we provide a physical setting for realizing non-Abelian off-diagonal

    geometric phases. The proposed setting can be implemented in a cyclic chain of four qubits

    with controllable nearest-neighbor interactions. Our proposal seems to be within reach in

    various nano-engineered systems and therefore opens up for first experimental test of the

    non-Abelian off-diagonal geometric phase.

  • 298.
    Azimi Mousolou, Vahid
    et al.
    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.
    Sjöqvist, Erik
    Uppsala University, Department of Chemistry.
    Non-Abelian off-diagonal geometric phases in nano-engineered four-qubit systems2013In: Europhysics letters, ISSN 0295-5075, E-ISSN 1286-4854, Vol. 103, no 6, p. 60011-Article in journal (Refereed)
    Abstract [en]

    The concept of off-diagonal geometric phase (GP) has been introduced in order to recover interference information about the geometry of quantal evolution where the standard GPs are not well-defined. In this Letter, we propose a physical setting for realizing non-Abelian off-diagonal GPs. The proposed non-Abelian off-diagonal GPs can be implemented in a cyclic chain of four qubits with controllable nearest-neighbor interactions. Our proposal seems to be within reach in various nano-engineered systems and therefore opens up for first experimental test of the non-Abelian off-diagonal GP.

  • 299.
    Azimi Mousolou, Vahid
    et al.
    University of Isfahan, Iran.
    Canali, Carlo M.
    Linnaeus University, Faculty of Technology, Department of Physics and Electrical Engineering.
    Sjöqvist, Erik
    Uppsala University.
    Spin-electric Berry phase shift in triangular molecular magnets2016In: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 94, no 23, article id 235423Article in journal (Refereed)
    Abstract [en]

    We propose a Berry phase effect on the chiral degrees of freedom of a triangular magnetic molecule. The phase is induced by adiabatically varying an external electric field in the plane of the molecule via a spin-electric coupling mechanism present in these frustrated magnetic molecules. The Berry phase effect depends on spin-orbit interaction splitting and on the electric dipole moment. By varying the amplitude of the applied electric field, the Berry phase difference between the two spin states can take any arbitrary value between zero and π, which can be measured as a phase shift between the two chiral states by using spin-echo techniques. Our result can be used to realize an electric-field-induced geometric phase-shift gate acting on a chiral qubit encoded in the ground-state manifold of the triangular magnetic molecule.

  • 300.
    Azimi Mousolou, Vahid
    et al.
    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.
    Sjöqvist, Erik
    Department of Quantum Chemistry, Uppsala University, Box 518, Se-751 20 Uppsala, Sweden.
    Unifying geometric entanglement and geometric phase in a quantum phase transition2013In: Physical Review A. Atomic, Molecular, and Optical Physics, ISSN 1050-2947, E-ISSN 1094-1622, Vol. 88, no 1, p. Article ID: 012310-Article in journal (Refereed)
    Abstract [en]

    Geometric measure of entanglement and geometric phase have recently been used to analyze quantum phase transition in the XY spin chain. We unify these two approaches by showing that the geometric entanglement and the geometric phase are respectively the real and imaginary parts of a complex-valued geometric entanglement, which can be investigated in typical quantum interferometry experiments. We argue that the singular behavior of the complex-valued geometric entanglement at a quantum critical point is a characteristic of any quantum phase transition, by showing that the underlying mechanism is the occurrence of level crossings associated with the underlying Hamiltonian.

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