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GCN Circular 35234

GRB 231129C: Swift-XRT observations
2023-11-30T13:59:14Z (7 months ago)
Phil Evans at U of Leicester <>
J. D. Gropp (PSU), S. Dichiara (PSU), K.L. Page (U. Leicester), A.P.
Beardmore (U. Leicester), M.G. Bernardini (INAF-OAB), E. Ambrosi 
(INAF-IASFPA) , M. Capalbi (INAF-IASFPA), J.A. Kennea (PSU) and P.A.
Evans (U. Leicester) reports on behalf of the Swift-XRT team:

Swift-XRT has performed follow-up observations of the
Fermi/GBM-detected burst GRB 231129C in a series of observations tiled
on the sky. The total exposure time is 1.5 ks, distributed over 4
tiles; the maximum exposure at a single sky location was 633 s. The
data were collected between T0+19.3 ks and T0+35.4 ks, and are entirely
in Photon Counting (PC) mode. 

One uncatalogued X-ray source has been detected, it is below the RASS
limit and shows no definitive signs of fading. Therefore, at the
present time we cannot confirm this as the afterglow. Details of this
source are given below:

Source 2:
  RA (J2000.0):  11.1769  =  00:44:42.45
  Dec (J2000.0): -81.9936  =  -81:59:37.0
  Error: 9.5 arcsec (radius, 90% conf.)
  Count-rate: 0.0208 [+0.0113, -0.0084] ct s^-1   
  Distance: 1341 arcsec from Fermi/GBM position.
  Flux: (8.6 [+4.7, -3.5])e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)

A catalogued source was also detected.

The results of the XRT-team automatic analysis of the tiled XRT
observations, including a position-specific upper limit calculator, are
available at

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

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