TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4694 SUBJECT: GRB060206: Swift XRT Refined Analysis DATE: 06/02/06 11:02:11 GMT FROM: David Morris at PSU/Swift-XRT D. Morris (PSU), D. Burrows (PSU), N. Gehrels (GSFC), J. Greiner (MPE), D. Hinshaw (GSFC-SPSYS) report on behalf of the Swift XRT team: We have analyzed the Swift XRT data from the first orbit of GRB 060206 (Morris et al., GCN4682), with a total exposure of 337 seconds. The refined XRT position is: RA(J2000) = 13h 31m 43.4s Dec(J2000) = +35d 03' 02" This position is 99.0 arcseconds from the BAT position given in GCN 4682 and 1.8 arcseconds from the optical afterglow position reported in GCN 4683 (Fynbo et al) and refined in GCN 4684 (Boyd et al). We estimate an uncertainty of 4 arcseconds radius (90% containment). The 0.2-10 keV light curve starts 65 seconds from the BAT trigger (T0). Due to the the spacecraft entry into the SAA, only a very small amount of data was collected during the first orbit. The available data suggest a decaying lightcurve but are too sparse to determine an accurate measure of the decay slope. A preliminary spectral fit to the PC data gives a spectral power law photon index of 2.0 ± 0.3 in the 0.2-10 keV band with NH of 4e20 +4e20/-3e20. The galactic NH value for this direction is 1e20. The unabsorbed 0.2-10 keV flux at the start of the XRT observation is estimated to be about 8E-11 erg/cm2/s. Due to the uncertain nature of the decay slope, we are currently unable to predict the expected flux at T+24hrs. Observations are ongoing and we will distribute further analysis as data become available. This circular is an official product of the Swift XRT Team.