{
  "bibcode": "2008GCN..7311....1D",
  "body": "P. D'Avanzo, D. Fugazza (INAF-OAB), L.A. Antonelli (INAF-OAR), S. \nCovino, G. Chincarini, C. Guidorzi, G. Tagliaferri (INAF-OAB), V. \nD'Elia, F. Fiore, S. Piranomonte, L. Stella (INAF-OAR), M. Della Valle \n(INAF-OAA), S. D. Vergani (DIAS-DCU) report on behalf of the MISTICI \ncollaboration:\n\nWe observed the optical afterglow of GRB 080212 (Ziaeepour et al., GCN \n7296) with the ESO-VLT equipped with the FORS2 camera in imaging mode at \nthree different epochs. Observations have been carried out in R-band on \nFeb 13.3101 UT, Feb 13.3682 UT and Feb 14.2838 UT (0.58, 0.64 and 1.55 \ndays after the burst, respectively).\n\nWe found that between the first two epochs the afterglow faded very \nrapidly, with a decay index of alpha ~ 5.5. Very likely, the afterglow \nunderwent a remarkable increase of its optical/NIR flux, probably \nrelated to the brightening observed in the X-rays about 4 hours before \nour VLT observations (see D'Avanzo et al., GCN 7310).\n\nAssuming the above decay index, we estimate R ~ 20.8 at the epoch of the \nREM detection (D'Avanzo et al., GCN 7302) with an implied colour R-H~5\n\nThe decay of the afterglow then slowed down between the last two epochs \nand we measure R~25 in our last observation.",
  "circularId": 7311,
  "createdOn": 1203017841000,
  "email": "paolo.davanzo@brera.inaf.it",
  "subject": "GRB 080212: VLT optical rapid decay",
  "submitter": "Paolo D'Avanzo at INAF-OAB  <paolo.davanzo@brera.inaf.it>",
  "eventId": "GRB 080212"
}