{
  "bibcode": "2009GCN.10060....1P",
  "body": "D. A. Perley (UC Berkeley) reports:\n\nFurther to observations the previous night (GCN 10058), I re-observed \nthe afterglow of GRB 091020 between UT 2009-10-22 12:23 and 13:25 using \nthe Nickel 40-inch telescope at Lick Observatory in a series of \nseventeen 180 second exposures (51 minutes total integration) in R-band.\n\nThe afterglow is detected in in the combined stack of all frames. \nCalibrating relative to the same SDSS standard stars as in GCN 10058, \nthe estimated magnitude of the afterglow at this time is:\n\nR = 21.81 +/- 0.23 mag  (t_mid = 39.29 hr)\n\nThe implied average decay index over the 24 hours since the previous \nobservation is alpha=0.87.",
  "circularId": 10060,
  "createdOn": 1256221320000,
  "email": "dperley@astro.berkeley.edu",
  "subject": "GRB 091020: Additional Lick observations",
  "submitter": "Daniel Perley at U.C. Berkeley  <dperley@astro.berkeley.edu>",
  "eventId": "GRB 091020"
}