LOFAR MSSS: detection of a low-frequency radio transient in 400 h of monitoring of the North Celestial PoleShow others and affiliations
2016 (English)In: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 456, no 3, p. 2321-2342Article in journal (Refereed) Published
Resource type
Text
Abstract [en]
We present the results of a four-month campaign searching for low-frequency radio transients near the North Celestial Pole with the Low-Frequency Array (LOFAR), as part of the Multifrequency Snapshot Sky Survey (MSSS). The data were recorded between 2011 December and 2012 April and comprised 2149 11-min snapshots, each covering 175 deg2. We have found one convincing candidate astrophysical transient, with a duration of a few minutes and a flux density at 60 MHz of 15–25 Jy. The transient does not repeat and has no obvious optical or high-energy counterpart, as a result of which its nature is unclear. The detection of this event implies a transient rate at 60 MHz of 3.9−3.7+14.7×10−4" style="position: relative;" tabindex="0" id="MathJax-Element-1-Frame" class="MathJax">3.9+14.7−3.7×10−4 d−1 deg−2, and a transient surface density of 1.5 × 10−5 deg−2, at a 7.9-Jy limiting flux density and ∼10-min time-scale. The campaign data were also searched for transients at a range of other time-scales, from 0.5 to 297 min, which allowed us to place a range of limits on transient rates at 60 MHz as a function of observation duration.
Place, publisher, year, edition, pages
2016. Vol. 456, no 3, p. 2321-2342
Keywords [en]
instrumentation, interferometers, techniques, image processing, radio continuum
National Category
Astronomy, Astrophysics and Cosmology
Research subject
Physics, Astroparticle Physics
Identifiers
URN: urn:nbn:se:lnu:diva-51519DOI: 10.1093/mnras/stv2797OAI: oai:DiVA.org:lnu-51519DiVA, id: diva2:915287
2016-03-292016-03-292019-02-27Bibliographically approved