{
  "bibcode": "2001GCN...958....1B",
  "body": "E. Berger (Caltech), D. A. Frail (NRAO), P. A. Price , J. S. Bloom, T. J.\nGalama (Caltech), R. Kudritzki (IFA), and F. Bresolin (ESO) report on\nbehalf of a larger collaboration:\n\n\"Beginning on February 22.21 UT we observed the entire BeppoSAX error\ncircle of GRB010220 (GCN#953) with the VLA at 4.86 and 8.46 GHz.  Inside\nthis region we detect one weak source (6.5 sigma), which is not cataloged\nin the NRAO VLA Sky Survey (NVSS), at RA=02:36:52.1, DEC=61:43:49.1, with\na conservative error of 0.3\" in each.  The detected source is clearly seen\nin the 4.86 GHz image, but it is only marginally detected at 8.46 GHz (~ 4\nsigma). We also detect several sources which correspond to cataloged NVSS\nsources.  We note that the uncataloged source is at the detection\nthreshold of NVSS.  Further observations at the VLA are planned.\n\nIn addition, R. Kudritzki and F. Bresolin obtained a single I- (100 s) and\nR-band (300 s) exposure using the Low-Resolution Imaging Spectrometer\n(LRIS; Oke et al. 1995) on both nights (21.313 and 22.293 Feb 2001 UT).\nUsing ~200 tie stars from the USNO A2.0 catalogue, an astrometric plate\nsolution was obtained for the Keck images.  No object is present at either\nepoch and either filter at the position of the radio source.  There is a\nvery bright star ~12 arcsec to the southwest of the radio position.  We\npreliminarily estimate the 3-sigma upper-limit to be R ~ 23.5 mag using an\nunsaturated star common to the USNO-A2.0 and the R-band image of the\nsecond night.  Given the proximity to the Galactic plane, infrared\nobservations are encouraged.\"\n\nThis message may be cited.",
  "circularId": 958,
  "createdOn": 982833986000,
  "email": "ejb@astro.caltech.edu",
  "subject": "GRB010220, Radio and Optical Observations",
  "submitter": "Edo Berger at Caltech  <ejb@astro.caltech.edu>",
  "eventId": "GRB 010220"
}