{
  "bibcode": "2006GCN..5077....1P",
  "body": "P.A. Price (IfA, Hawaii), E. Berger (OCIW), D.B. Fox (Penn State), S.B.\nCenko and A. Rau (Caltech) report on behalf of a larger collaboration:\n\nWe have obtained a second epoch of imaging with the Gemini North\ntelescope of the XRT localisation of the short/hard GRB 060502B (GCN\n#5063).  The observations commenced at 2006 May 4.43 UTC (1.7 days after\nthe GRB), and consisted of 5 x 300 sec exposures in r'.  These\nobservations have better seeing and depth than our first epoch\nobservation (2006 May 3.43 UTC, 0.7 days after the GRB; GCN #5071). \nImage subtraction does not reveal any variable sources within the XRT\nerror circle.  In particular, the galaxy (\"G1\") and source (\"S1\")\nidentified in our previous observations have not appreciably changed in\nbrightness.\n\nThese observations place a limiting magnitude of any optical afterglow\nin our first epoch observation of approximately R ~ 24.3 mag, based on\nassuming R=17.5 mag for USNO-B1 star 426-035230 (RA,Dec =\n278.92572,52.61611).\n\nWe identify in the second epoch image an additional faint source (\"S2\")\nat R ~ 25.8 mag in the error circle at approximate coordinates:\n\n        18:35:45.86 +52:37:50.0 J2000\n\nAn image of the field is available at:\n\n        http://www.ifa.hawaii.edu/~price/grb060502b.gif\n\nNote that the magnitude of the faint galaxy (\"G1\") in GCN #5071 is\nmeasured to be R ~ 23.8 mag in our first epoch observation, using the\nabove calibration, consistent with the observation of Halpern & Mirabal\n(GCN #5072).  We apologise for any inconvenience this error may have\ncaused.\n\nWe thank the Gemini North observing team for obtaining these\nobservations.",
  "circularId": 5077,
  "createdOn": 1146883407000,
  "email": "price@ifa.hawaii.edu",
  "subject": "GRB 060502b: Second epoch Gemini observations",
  "submitter": "Paul Price at IfA,UH  <price@ifa.hawaii.edu>",
  "eventId": "GRB 060502B"
}