TITLE:   GCN CIRCULAR
NUMBER:  36564
SUBJECT: GRB 240529A: Swift-XRT refined Analysis
DATE:    24/05/29 14:50:35 GMT
FROM:    Phil Evans at U of Leicester <pae9@star.le.ac.uk>

S. Dichiara (PSU), J.A. Kennea (PSU), K.L. Page (U. Leicester), A.P.
Beardmore (U. Leicester), A. Melandri (INAF-OAR), T. Sbarrato
(INAF-OAB), P. D'Avanzo (INAF-OAB), A. Tohuvavohu (U. Toronto) and P.A.
Evans report on behalf of the Swift-XRT team:

We have analysed 5.8 ks of XRT data for GRB 240529A, from 107 s to 19.1
ks after the  BAT trigger. The data comprise 344 s in Windowed Timing
(WT) mode (the first 10 s were taken while Swift was slewing) with the
remainder in Photon Counting (PC) mode. A spectrum formed from the WT
mode data can be fitted with an absorbed power-law with a photon
spectral index	of 1.945 (+0.015, -0.025). The best-fitting absorption
column is  consistent with the Galactic value of 4.1 x 10^21 cm^-2
(Willingale et al. 2013). The PC mode spectrum has a photon index of
2.07 (+0.05, -0.04) and a best-fitting absorption column consistent
with the Galactic value. The counts to observed (unabsorbed) 0.3-10 keV
flux conversion factor deduced from this spectrum  is 3.8 x 10^-11 (6.0
x 10^-11) erg cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:	     4.06 (+0.15, -0.00) x 10^21 cm^-2
Galactic foreground: 4.1 x 10^21 cm^-2
Excess significance: <1.6 sigma
Photon index:	     2.07 (+0.05, -0.04)

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/01231488.

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