{
  "bibcode": "2007GCN..6892....1O",
  "body": "A. Oksanen (Nyrola Observatory, Jyvaskyla, Finland), M. Templeton (AAVSO) \nand A. Henden (AAVSO) report further details on optical observations of \nGRB071010B (GCN #6871, Markwardt et al.; GCN #6873 Oksanen; GCN #6878 \nKennea et al.; GCN #6884 Kann et al.):\n\nFurther to the initial report given in GCN #6873, Arto Oksanen reports \nunfiltered photometry of the GRB 071010B afterglow spanning 2007 Oct 10 \n21:02:33 UT to 2007 Oct 11 03:24:27 UT (T0 + 17 minutes to T0 + 6 hours 39 \nminutes post-burst).  The data are reasonably well fit by a single power \nlaw with index -1.14.  The measured unfiltered magnitudes are \napproximately 0.3 magnitudes fainter than the Rc magnitudes reported by \nKann et al (GCN #6884) taken at the same time, which is consistent with \ndifferences in zero-point calibration and bandpass.  It should be noted \nthat this field is covered by the SDSS, and that the AAVSO will obtain a \nBVRI calibration with the Sonoita Research Observatory, weather \npermitting.\n\nOksanen also reports additional preliminary Ic and V-band magnitudes:\n\n2007 Oct 10, 21:32 UT   Ic = 17.64 +/- 0.05\n2007 Oct 10, 21:52 UT   V  = 18.30 +/- 0.05\n\nBoth magnitudes are calibrated relative to the transformed SDSS ugriz\nmagnitudes for the object at RA 10:01:54.62, Dec +45:40:29.0 (J2000).\n\nFurther details of these observations, light curves, and analyses are in\npreparation for publication in the electronic Journal of the AAVSO.\n\nFull details of the observations are available at the following URL:\nftp://ftp.aavso.org/grb/ArtoOksanen_GRB071010B_2454384.45422_.txt\n\nThe AAVSO thanks the Curry Foundation for their continued support of the\nAAVSO International High Energy Network.",
  "circularId": 6892,
  "createdOn": 1192131231000,
  "email": "matthewt@aavso.org",
  "subject": "GRB 071010B optical photometry",
  "submitter": "AAVSO GRB Network at AAVSO  <matthewt@aavso.org>",
  "eventId": "GRB 071010B"
}