[vsnet-grb-info 2795] GRB 060202: Swift XRT Team Refined Analysis

[GCN Circulars]

TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  4632
SUBJECT: GRB 060202: Swift XRT Team Refined Analysis
DATE:    06/02/02 14:24:33 GMT
FROM:    Jamie A. Kennea at PSU/Swift-XRT  <kennea at astro.psu.edu>

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D. Morris (PSU), D. Fox (PSU), D. Burrows (PSU), N. Gehrels (GSFC), F.=20
Marshall (GSFC), P. Boyd (GSFC-UMBC), J. Kennea (PSU), H. Krimm=20
(GSFC/USRA), D. Palmer (LANL) report on behalf of the Swift XRT team:

We have analyzed the Swift XRT data from the first orbit observation of=20
GRB 060202 (Fox et al., GCN4629), with a total exposure of 540 seconds.=20
The refined XRT position is:

RA(J2000) =3D 02h 23m 23.02s
Dec(J2000) =3D +38d 23' 05.7"

This position is 82.8 arcseconds from the BAT and 3.7 arcseconds from the=
=20
XRT position given in GCN 4629. We estimate an uncertainty of 4 arcseconds=
=20
radius (90% containment).

The 0.2-10 keV light curve in Windowed Timing (WT) mode starts 148.8=20
seconds from the BAT trigger (T0). The lightcurve shows a steep early=20
decay index of 2.7 followed by a flattening to a decay index of 0.2 at=20
T+310s.

A preliminary spectral fit to the WT data gives a spectral power law=20
photon index of 2.52 =B1 0.03 in the [0.2-10] keV band with NH of 5.8e21 +/=
-=20
2e20, well above the galactic NH value for this direction of 5.1e20. The=20
unabsorbed 0.2-10 keV flux at the start of the XRT observation is=20
estimated to be about 2.5E-8 erg/cm2/s, flattening at a flux level of=20
about 2E-9 erg/cm2/s. We do not have sufficient data at this time to allow=
=20
an accurate extrapolation of the flux to T+24 hr.

This Circular is an official product of the Swift XRT Team.
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