{
  "bibcode": "2008GCN..7580....1B",
  "body": "A. Block (Seeing In The Dark Internet Telescope, and Steward\nObservatory, Tucson, AZ) and M. Templeton (AAVSO) report on behalf of\nthe AAVSO International High Energy Network the following observations\nand analysis of the optical afterglow of GRB 080330 (Mao et al., GCN\nCircular #7537; Klotz, Boer, and Atteia, GCN #7536):\n\nAdam Block reports unfiltered photometry of the GRB 080330 afterglow\nspanning 2008 March 30.1675 UT to 2008 March 30.3273, taken with the\nSeeing In The Dark Internet Telescope 14-inch Celestron SCT, using an\nSBIG ST1001 camera, located near Mayhill, New Mexico.  Forty-seven,\n300-second unfiltered exposures were obtained beginning 20 minutes\npost-burst, and continuing through t0 + 0.1736 days. Data acquisition\nbegan after the reported peak (D'Avanzo, et al., GCN #7554), but during\nthe early decay epoch.  A break in the light curve is apparent at\napproximately 25 minutes after the trigger; only one data point was\nobtained prior to this point, and so a slope cannot be reliably derived. \nAfter t0 + 25 minutes, the data are reasonably well fit with a power law\nindex of -1.104 +/- 0.001, with a zero point unfiltered magnitude of\n22.65 (m = m(t+1day)).  However, the light curve appeared to briefly\nrebrighten by more than 0.2 magnitudes (1-sigma error = 0.09 mag)\napproximately 70 minutes post-burst, suggesting a late-time\nmanifestation of the rebrightening seen during early light (Schaefer and\nGuver, GCN #7538).  These observations are consistent with other\noptical observations taken during this time frame; observations through\nt0 + 250 minutes do not show evidence for the steeper slope described by\nSergeev et al (GCN #7556) for data taken at t > t0 + 0.5 days,\nsuggesting this break occurred between the end of these observations and\nthe start of observations by Sergeev et al.\n\nA report detailing these observations is available at the following URL:\n\nftp://ftp.aavso.org/grb/AdamBlock_GRB080330_2454558.33910_.txt\n\nThe initial image of the GRB field is available at the following URL:\n\nftp://ftp.aavso.org/grb/AdamBlock_GRB080330_2454558.33910_.fits\n\nA light curve of the unfiltered photometry is available at the following\nURL:\n\nhttp://www.caelumobservatory.com/outgoing/grb080330LOG.jpg\n\nPhotometry and a full description of the observations will appear in the\nJournal of the AAVSO, and are available from A. Block upon request to\nngc1535@caelumobservatory.com.\n\nThe AAVSO thanks the Curry Foundation for their continued support of the\nAAVSO International High Energy Network.",
  "circularId": 7580,
  "createdOn": 1207766218000,
  "email": "matthewt@aavso.org",
  "subject": "GRB 080330 optical observations",
  "submitter": "AAVSO GRB Network at AAVSO  <matthewt@aavso.org>",
  "eventId": "GRB 080330"
}