{
  "bibcode": "2005GCN..3921....1D",
  "body": "P. D'Avanzo (INAF/OAB), L. A. Antonelli (INAF/OAR), S. Covino\n(INAF/OAB), D. Malesani (SISSA), G. Tagliaferri, G. Chincarini\n(INAF/OAB) on behalf of the MISTICI collaboration report:  \n\nWe observed the field of GRB 050904 (Cummings et al., GCN 3910), in the\nJ band with the 3.6m TNG telescope (equipped with NICS) and with the ESO\nVLT-UT1 (equipped with ISAAC). We don't detect the NIR source at the\nposition indicated by Haislip et al. (R.A. 00:54:51.3, Dec. 14:05:09.7,\nGCN 3913, 3919) and by Klotz et al. (GCN 3917) to a limit J > 22\n(5sigma). We also note that this position is ~ 6 arcsec out from the XRT\nerror box (Mineo et al., GCN 3920) and ~ 11\" away from its center.\n\nWe detect however a single fading source inside the XRT error box, which\nis likely the NIR counterpart of GRB 050904. Its coordinates are:\n\n  R.A.(J2000) = 00:54:50.8\n  Dec.(J2000) = +14:05:10.0\n\nThe detected source faded by 0.30 +/- 0.15 mag between the two epochs\n(24.7 and 26 h after the burst, respectively). That source has a J\nmagnitude which is consistent with the one expected from the source\nproposed by Haislip et al. with a decay slope of t^-1,\n\n\nA finding chart is available at the following URL:\nhttp://www.sissa.it/~malesani/GRB/050904/GRB050904_finder.jpg\n\nWe thank the TNG and ESO staff, in particular Marco Pedani, Poshak\nGandhi and Nancy Ageorges for carefully performing our observations and\nquickly providing the data.\n\nThis message can be cited.",
  "circularId": 3921,
  "createdOn": 1125920291000,
  "email": "davanzo@merate.mi.astro.it",
  "subject": "GRB 050904: NIR object inside the XRT error box",
  "submitter": "Paolo D'Avanzo at INAF-OAB  <davanzo@merate.mi.astro.it>",
  "eventId": "GRB 050904"
}