[vsnet-grb-info 18757] GRB 161123A: Swift-XRT observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  20206
SUBJECT: GRB 161123A: Swift-XRT observations
DATE:    16/11/23 16:12:34 GMT
FROM:    Andy Beardmore at U Leicester  <ab271 at leicester.ac.uk>

A. D'Ai (INAF-IASFPA), A. Melandri (INAF-OAB), L.M. McCauley (PSU),
J.A. Kennea (PSU), B. Sbarufatti (INAF-OAB/PSU), A.P. Beardmore (U.
Leicester), S.L. Gibson (U. Leicester), P. D'Avanzo (INAF-OAB) and P.A.
Evans (U. Leicester) report on behalf of the Swift-XRT team:

Swift-XRT has performed follow-up observations of the MAXI-detected
burst GRB 161123A (Hanyu et al. GCN Circ. 20203) in a series of
observations tiled on the sky. The total exposure time is 2.6 ks,
distributed over 7 tiles; the maximum exposure at a single sky location
was 825 s. The data were collected between T0+21.8 ks and T0+28.0 ks,
and are entirely in Photon Counting (PC) mode. 

No X-ray sources have been detected. The 3-sigma upper limit in the
field (not including the regions where the tiles overlap) ranges from
~0.02 to ~0.05 ct s^-1, corresponding to a 0.3-10 keV observed flux of
8.2e-13 to 1.9e-12 erg cm^-2 s^-1 (assuming a typical GRB spectrum).

The results of the XRT-team automatic analysis of the tiled XRT
observations, including a position-specific upper limit calculator, are
available at http://www.swift.ac.uk/xrt_products/TILED_GRB00061.

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