{
  "bibcode": "2014GCN.15809....1P",
  "body": "D. A. Perley (Caltech) reports on behalf of a larger collaboration:\n\nThe Palomar 60-inch telescope responded automatically to the Swift alert \nfor GRB 140209A (Cenko et al., GCN 15808) and began a sequence of \n60-second exposures in r, i, and z filters at 07:35:30 UT, 4.55 minutes \nafter the BAT trigger.  In the reduced images, we clearly detect a \nfading, uncatalogued optical counterpart inside the BAT error circle at \nthe following location:\n\nRA  =  05:25:19.034\nDec = +32:29:53.18\n(+/- 0.6 arcsec)\n\nCalibrated relative to USNO-B1.0, the source fades steadily from R=17.6 \nin the first r-band image to R=19.4 at 41.1 minutes post-GRB, which \nidentifies it as the likely optical afterglow of this event.",
  "circularId": 15809,
  "createdOn": 1391938184000,
  "email": "dperley@astro.caltech.edu",
  "subject": "GRB 140209A: P60 optical afterglow detection",
  "submitter": "Daniel Perley at Caltech  <dperley@astro.caltech.edu>",
  "eventId": "GRB 140209A"
}