[vsnet-grb-info 8070] XRF 090702: Swift-XRT refined analysis

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  9609
SUBJECT: XRF 090702: Swift-XRT refined analysis
DATE:    09/07/03 18:26:52 GMT
FROM:    Boris Sbarufatti at INAF-IASF-Pa  <sbarufatti at ifc.inaf.it>

Sbarufatti B., Mangano V. (INAF-IASFPA) report on behalf of the Swift  
Team:

We have analyzed the Swift-XRT data of XRF 090702 (Paizis, et al., GCN  
Circ. 9603) comprising 6 ks in Photon Counting (PC) mode from T+16.5  
ks to T+25.4 ks.

The best position for the X-ray afterglow is the XRT UVOT-enhanced  
position:
RA, Dec = 175.89704, +11.50161 which is equivalent to:

RA (J2000):	11h 43m 35.29s
Dec (J2000):   +11d 30' 05.8"

with an uncertainty of 5.0 arcsec (radius, 90% confidence).

The light-curve consists of two data points at the level of some 1E-3  
counts/s, and shows evidence of a fading behaviour. A power-law  
extrapolation of the available data indicates a count-rate of 9.4E-5  
counts/s at T+48 h.

The average spectrum was fitted using Cash statistics with an absorbed  
power-law model. The absorbing column NH was fixed at the Galactic  
value of 3.5E20 cm^-2, the photon index is 1.9+/-0.4. The observed  
(unabsorbed) flux is 2.8(3.0)E-13 ergs cm^-2 s^-1. The C-statistic is  
29.3 with 32 bins. The count-rate to flux conversion factor is 4.4E-11.
All quoted errors are at 90% confidence level.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00020106

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