{
  "bibcode": "2007GCN..6082....1H",
  "body": "J. P. Halpern & N. Mirabal (Columbia U.) report on behalf of the\nMDM Observatory GRB follow-up team:\n\n\"Monitoring of the afterglow of GRB 070208 (GCNs 6077, 6078, 6079)\nin the R-band on the MDM 1.3m telescope consisted of a series of\n10-minute exposures beginning on Feb. 8 09:25 UT and ending at\n13:12 UT, thus spanning the time 0.25-4 hours after the burst.\nPartly cloudy conditions, together with bright moonlight,\nresulted in images of highly variable quality.  Nevertheless,\nwe see the fading optical transient within the Swift XRT error\ncircle (Sato et al., GCN 6074).  In agreement with the GCNs\nlisted above, we find the OT 3.0\" west and 3.3\" south of the\ncenter of a galaxy visible on the POSS (Mirabal & Halpern, GCN 6075)\nand in pre-burst SDSS images (Cool et al., GCN 6080).\n\nPreliminary magnitudes for the OT, calibrated with respect to\nUSNO B1.0 magnitudes of nearby stars, are R=20.04+/-0.08 for the\nfirst exposure centered at 09:30 UT, and R=21.5+/-0.2 for a summed\n30-minute exposure centered at 12:55 UT.  Some contamination from\nthe nearby galaxy is possible in this analysis.  Quoted uncertainties\nare statistical only.  This corresponds to a mean power-law decay\nindex of -0.55.\n\nIt is not yet clear from this collection of images, both SDSS\nand MDM, if the visible galaxy is the host, or if we should wait\nto see if a fainter galaxy underlies the OT of this judged long\nburst (Markwardt et al., GCN 6081).\n\nImages are posted at http://www.astro.columbia.edu/~jules/grb/070208/\n\nThis message may be cited.\"",
  "circularId": 6082,
  "createdOn": 1170964615000,
  "email": "jules@astro.columbia.edu",
  "subject": "GRB 070208: MDM Optical Decay",
  "submitter": "Jules Halpern at Columbia U.  <jules@astro.columbia.edu>",
  "eventId": "GRB 070208"
}