TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2466 SUBJECT: GRB 031203: IR REM Observations DATE: 03/12/04 13:28:06 GMT FROM: Gianpiero Tagliaferri at OAB-INAF GRB 031203: IR REM Observations F.M.Zerbi, G.Chincarini, S. Covino, E. Molinari, A. Di Paola, D. Fugazza, V. Testa, M. Rodono', L.A. Antonelli, P. Conconi, G. Cutispoto, L. Nicastro, G. Tosti, L. Burderi, S. Campana, C. Campeggi, G. Crimi, R. Cunniffe, J. Danzinger, A. Fernandez-Soto, F. Fiore, F. Frontera, G. Gentile, G. Ghisellini, P. Goldoni, G. Israel, B. Jordan, D. Lazzati, D. Lorenzetti, D. Malesani, E. Martinetti, N. Masetti, R. Mazzoleni, B. Mc Breen, A. Melandri, S. Messina, E. Meurs, A. Monfardini, G. Nucciarelli, M. Orlandini, J. Paul, E. Palazzi, E. Pian, P. Saracco, S. Sardone, A. Simoncelli, M. Stefanon, L. Stella, L. Tagliaferri, M. Tavani, G. Tosti, S. Vergani, F. Vitali. The REM telescope, currently in commissioning phase, observed the field of the INTEGRAL GRB 031203 starting at 4 December 04h15m UT in J, H and Ks filters. Observation in the visible band with ROSS spectrograph were not possible at this stage for technical reasons. We found an object not present in the 2MASS catalog in the S1 XMM-Newton error box (GCN #2464). This object is found in the H and Ks images (approximate magnitudes H=14.9 +/- 0.2, Ks=13.4 +/- 0.2) and not in the J image (J upper limit 16.5). Note that this object would have been detected in the 2MASS H and K filters. The transient is nearby (~5") to another weak object already present in the 2MASS. The coordinates of the transient are (J2000): R.A. = 08h 02m 29.7s Dec. = -39deg 51' 09.5". At this stage of reduction the position error is expected to be of the order of 1". This message may be cited.