{
  "bibcode": "2005GCN..3031....1T",
  "body": "N. Tanvir, S. Pak, R. Priddey, M. Hughes (U. Hertfordshire),\nE. Rol, A. Levan, P. O'Brien (U. Leicester), C. Simpson (U. Durham),\nE. Vardoulaki (U. Oxford), T. Carroll (JACH) report on behalf of a\nlarger collaboration:\n\nWe have obtained a second epoch of UKIRT/UFTI K-band imaging of\nthe Swift/BAT position reported for GRB 050215B.  Seeing was\nagain good (approx 0.5 arcsec compared to 0.4 arcsec on the\nprevious night).  The observation began at Feb 16.49 UT, roughly\n34 hrs post burst.\n\nWe find no variable sources within the XRT error circle for the object\nreported by Page et al (GCN circular 3027). However we find a faint,\napparently variable, point source about 30 arcsec from the centre of the\nBAT error circle.  It has magnitude K=20.23+-0.11 on night 1 and\nK=20.75+-0.22 on night 2 (both measured in a 0.9 arcsec aperture),\nwhich we believe is therefore a good candidate for the afterglow of\nthis burst.\n\nAlthough near the detection limit, the source on the second night\nmay be slightly extended (possibly also on the first), which would\nindicate a host contribution, and hence that particularly the second\nmagnitude should be treated as an upper limit on the afterglow\nmagnitude.\n\nThe location of this object, is 15.7 arcsec E and 12.7 arcsec S\nof the 2MASS/USNO-B1 catalogued object (whose magnitude we refine to\nK=15.46 based on our standard star calibration).  ie. in the USNO-B1\nsystem the candidate afterglow is located at:\n\n 11:37:47.90 40:47:45.6\n\nPostage stamp images are available on:\n\n  http://star-www.herts.ac.uk/~nrt/050215b.html\n\nFurther followup is ongoing.",
  "circularId": 3031,
  "createdOn": 1108651713000,
  "email": "nrt@ast.cam.ac.uk",
  "subject": "GRB 050215B: candidate afterglow",
  "submitter": "Nial Tanvir at IofA U.Cambridge  <nrt@ast.cam.ac.uk>",
  "eventId": "GRB 050215B"
}