TITLE: GCN CIRCULAR NUMBER: 41234 SUBJECT: GRB 250805A: Swift-XRT observations DATE: 25/08/05 07:51:10 GMT FROM: Phil Evans at U of Leicester pae9@star.le.ac.uk

J.A. Kennea (PSU), G. Cusumano (INAF-IASF PA) and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team:

The XRT began observing the field of GRB 250805A at 07:08:01.8 UT, 3532.9 seconds after the BAT trigger. Using promptly downlinked data we find an uncatalogued X-ray source located at RA, Dec 24.20214, -81.40161 which is equivalent to: RA(J2000) = 01h 36m 48.51s Dec(J2000) = -81d 24' 05.8" with an uncertainty of 3.7 arcseconds (radius, 90% containment). This location is 30 arcseconds from the BAT onboard position, within the BAT error circle. This position may be improved as more data are received; the latest position is available at https://www.swift.ac.uk/sper.

A power-law fit to a spectrum formed from promptly downlinked event data gives a column density in excess of the Galactic value (8.44 x 10^20 cm^-2, Willingale et al. 2013), with an excess column of 4.6 (+3.34/-2.82) x 10^21 cm^-2 (90% confidence).

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