TITLE: GCN GRB OBSERVATION REPORT NUMBER: 5386 SUBJECT: GRB 060801: optical observations at FORS2/VLT DATE: 06/08/02 03:26:19 GMT FROM: Silvia Piranomonte at OAR S. Piranomonte (INAF, OAR), S. Covino (INAF, OABr), D. Malesani (SISSA/ISAS), G.Tagliaferri (INAF, OABr), G. Chincarini (Univ Milano-Bicocca), L. Stella (INAF, OARm), report on behalf of the MISTICI collaboration: We observed the position of XRT error circle of GRB 060801 (Racusin, et al., GCN Circ. 5378) with FORS2/VLT on August 2.0125 UT (about 12 hours post burst). Eight exposures lasting 300s were acquired with the FORS2 instrument. Preliminary analysis shows that the objects from Castro-Tirado et al. (GCN 5384) are clearly evident (A: 14:12:01.65,+16:59:02.0 and B: 14:12:01.21, +16:58:55.7) with R magnitudes about 20.8 and 22.6, respectively. Object B seems to have a possible extended emission. Inside the XRT errorbox we find two more ojects. One near the limit of the error box (C: 14:12:01.88, 16:58:53.7 with R mag about 22.6) and one faint, possible extended object (object D: 14:12:01.40,+16:58:54.7) with R magnitude about 23.6. Objects B is distant 3-3.5 arcsec from object D. Magnitudes were calibrated with the USNO catalogue and absolute uncertainty is likely of the order of 0.5 magnitudes. At the present stage, therefore, no object can be easily singled out as the GRB afterglow, although source B and D could be the GRB host galaxy. Further analysis are on-going We thank the ESO staff for excellently performing these observations in service mode. This message may be cited" "We observed the position of XRT error circle of GRB 060801 (Racusin, et al., GCN Circ. 5378) with FORS2/VLT on August 2.0125 UT (about 12 hours post burst). Eight exposures lasting 300s were acquired with the FORS2 instrument. Preliminary analysis shows that the objects from Castro-Tirado et al. (GCN 5384) are clearly evident (A: 14:12:01.65,+16:59:02.0 and B: 14:12:01.21,+16:58:55.7) with R magnitudes about 20.8 and 22.6, respectively. Object B appear to have a possible extended emission. Inside the XRT errorbox we find two ojects. One near the limit of the error box (C: 14:12:01.88, 16:58:53.7 with R mag about 22.6) and one faint, possible extended object (object D: 14:12:01.40,+16:58:54.7) with R magnitude about 23.6. Objects B is distant 3.5 arcsec from object D. Magnitudes were calibrated with the USNO catalogue and absolute uncertainty is likely of the order of 0.5 magnitudes. At the present stage, therefore, no object can be easily singled out as the GRB afterglow, although source D could be the GRB host galaxy. Further analysis are on-going. We thank the ESO staff for excellently performing these observations in service mode. This message may be cited" ------------------------------------------------- This mail sent through IMP: http://horde.org/imp/