{
  "bibcode": "2007GCN..7010....1P",
  "body": "L. K. Pollack (UC Santa Cruz), M. A. van Dam (WM Keck Observatory), D. \nLe Mignant (WM Keck Observatory, UC Santa Cruz), E. M. Johansson (WM \nKeck Observatory), D. A. Perley (UC Berkeley), and J. S. Bloom (UC \nBerkeley) report:\n\nOn October 19 at UT 05:14:04 we observed the afterglow of GRB 071003 \n(Schady et al., GCN 6837; Li, GCN 6838; Cenko et al. GCN 6839) with the \nNIRC2 narrow-field camera (0.01 arcsec/pixel) on Keck II using natural \nguide star adaptive optics (NGS AO).  We took 15 exposures, each of 60 \nseconds and 2 coadds, resulting in a total integration time of 30 \nminutes.  The natural guide star is located 6.5 arcseconds west of the \nafterglow position, and has R=11 mag.\n\nThe K=12.011 +/- 0.024 mag 2MASS star located 7.8 arcseconds east of the \nafterglow position was used as a photometric calibrator. Assuming no \nchanges in the AO-corrected PSF over these distances, we measure the \nafterglow to have K' = 21.58 +/- 0.03.  We find no host galaxy at the \nposition of the afterglow.\n\nWe detect the galaxy previously reported by Perley et al. (GCN 6874) at \na position 2.07 arcseconds southwest of the afterglow position. \nPhotometry on this extended object is difficult in the presence of the \nbright nearby star; however, we measure the galaxy to have an \napproximate brightness of K'=19.1 +/- 0.1 mags within an aperture of a \n0.5 arcsecond radius.\n\nAn image of the observations has been posted to:\nhttp://www.ucolick.org/~pollack/071003.jpg .\n\nWe thank the Keck staff for performing these observations.  In \nparticular, we would like to acknowledge the help of Al Conrad.",
  "circularId": 7010,
  "createdOn": 1193439067000,
  "email": "dperley@astro.berkeley.edu",
  "subject": "GRB 071003: Infrared Photometry with Keck Adaptive Optics",
  "submitter": "Daniel Perley at U.C. Berkeley  <dperley@astro.berkeley.edu>",
  "eventId": "GRB 071003"
}