{
  "bibcode": "2005GCN..3817....1S",
  "body": "P. Schady (MSSL/PSU), D. Fox (PSU), P. Roming (PSU), A. Cucchiara (PSU), \nM. Still (GSFC), S.T. Holland (GSFC/USRA) K. Mason (MSSL), A. Blustin \n(MSSL), N. Gehrels (GSFC), on behalf of the Swift UVOT team\n\nThe Swift Ultra-Violet Telescope (UVOT) began observations of GRB050815 on \nAugust 15th, 2005 at 17:26:25.6 UT, 67s after the BAT trigger. The UVOT \ntook a 100s exposure in the V band and two 10s exposures in the M1 and W2 \nUV filters before the source was occulted by the Earth. The next set of \nobservations were made ~1hr after the BAT trigger.\n\nAnylsis of the early time data reveals an uncatalogued source in the V \nband at position\n\nRa, Dec = 19:34:23.147, +09:08:47.47\n\nwith an estimated uncertainty of 0.5\". Astrometry was performed using \nstars from the USNO-catalogue. The source is no longer detected in the \nsecond epoch of V band images, confirming it's fading nature, and leading \nus to conclude this to be the afterglow. No detections are made in any \nother of the UVOT filters at the 3-sigma significance level. \n\nPhotometry carried out on this source requires additional care due to the \nproximity ofvarious bright stars (~16-18mag). We estimate the afterglow to \nhave decayed by about 1 magnitude in 1 hour. Further analysis is still\nundergoing.",
  "circularId": 3817,
  "createdOn": 1124162486000,
  "email": "ps@mssl.ucl.ac.uk",
  "subject": "GRB050815: Optical afterglow detection by Swift UVOT",
  "submitter": "Patricia Schady at MSSL/Swift  <ps@mssl.ucl.ac.uk>",
  "eventId": "GRB 050815"
}