TITLE:   GCN CIRCULAR
NUMBER:  16015
SUBJECT: GRB 140320C: Swift-XRT detection of the X-ray afterglow
DATE:    14/03/21 07:10:35 GMT
FROM:    Kim Page at U.of Leicester  <klp5@leicester.ac.uk>

C. Pagani and K.L. Page (U. Leicester) report on behalf of the Swift-XRT team:

We have analysed 4 ks of XRT data for the INTEGRAL detected GRB 140320C
(Mereghetti et al. GCN Circ. 16007), from 19.5 s to 37.2 ks after the
trigger. The data are entirely in Photon Counting (PC) mode. We detect an
uncatalogued X-ray source. Using 1552 s of XRT Photon Counting mode data
astrometrically corrected X-ray position (using the XRT-UVOT alignment and
matching UVOT field sources to the USNO-B1 catalogue): RA, Dec =
134.39401, 71.19829, which is equivalent to:

RA(J2000) =   08 57 34.56
Dec(J2000) =  71 11 53.9

with an uncertainty of 2.6 arcsec (radius, 90% confidence). This is 28
arcsec from the initial INTEGRAL position, within the INTEGRAL error
circle. This is consistent with the optical source N3 from Volnova et al.
(GCN 16012).

The source has faded from a count rate of 0.013 (+/- 0.003) at 20.5 ks
after the INTEGRAL trigger to 0.003 (+0.002,-0.001) by 33.9 ks, so we
confirm it as the X-ray afterglow.

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