[vsnet-grb-info 9043] Probable SGR 1833-0832: Swift-XRT refined analysis

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  10531
SUBJECT: Probable SGR 1833-0832: Swift-XRT refined analysis
DATE:    10/03/20 13:37:15 GMT
FROM:    Jonathan Gelbord at PSU/Swift  <jgelbord at astro.psu.edu>

J.M. Gelbord (PSU) and L. Vetere (PSU) report on behalf of the
Swift-XRT team:

We have analysed 22.5 ks of XRT data for SGR 1833-0832 (Gelbord
et al. GCN Circ. 10526), from 80 s to 52.8 ks after the BAT trigger.
The data are entirely in Photon Counting (PC) mode. The enhanced XRT
position for this burst was given by Evans et al. (GCN Circ. 10530).

The light curve is consistent with a SGR but not a GRB, as the
present data exhibit little variability and do not decay. When
the light curve is modelled with a power-law, the best-fitting
alpha = 0.05 (+0.19,-0.17). The mean aperture-corrected count rate
is 0.031 (+/-0.002) counts per second.

A spectrum formed from these data can be fitted with an absorbed
power-law with a photon spectral index of 3.21 (+0.69, -0.64). The
best-fitting absorption column is 1.38 (+0.35, -0.30) x 10^23 cm^-2,
in excess of the Galactic value of 1.7 x 10^22 cm^-2 (Kalberla
et al. 2005). The counts to observed (unabsorbed) 0.3-10 keV flux
conversion factor deduced from this spectrum is 1.1 x 10^-10
(4.7 x 10^-9) erg cm^-2 count^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00416485.

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