[vsnet-grb-info 2960] GRB 060219: Swift-XRT Team refined analysis

[GCN Circulars]

TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  4797
SUBJECT: GRB 060219: Swift-XRT Team refined analysis
DATE:    06/02/20 12:30:27 GMT
FROM:    Alberto Moretti at Obs Brera Merate  <moretti at merate.mi.astro.it>

A. Moretti (INAF-OAB) reports on behalf of the Swift XRT team:

Analysing the first seven orbits of data (8.6 ks in Photon Counting mode,
in the range from 120 s to 25 ks from the BAT trigger),
the following refined position for the X-ray afterglow was determined:

RA(J2000) =   16h 07' 21.10"
Dec(J2000) = +32d 18' 56.3"

with an estimated uncertainty of 3.9 arcsec (90% containment). This is
72 arcsec from the BAT position reported by Bathelmy et al. (GCN 4795)
and 0.5 arcsec from the XRT position given Moretti et al. (GCN 4793).

The light-curve shows a single power decay of 0.65 +/- 0.20 from the
beginning of the observation (120 s after the trigger) up to 25 ks.

The spectrum can be fitted with a power-law of photon index Gamma = 2.1
+/- 0.2, assuming a Galactic column of 2.4E+20 cm^-2; there is no evidence
for excess NH in these data.

Assuming the current decay slope of 0.65 continues, and using the spectral
fit to the first orbit of data, the XRT count rate is predicted to be
0.006 counts/s at 24 hours, corresponding to an observed flux of 3.0e-13 
erg cm^-2 s^-1.

This circular is an official product of the Swift-XRT Team.