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GCN Circular 18237

GRB 150902A: Swift-XRT observations
2015-09-04T14:55:37Z (9 years ago)
Boris Sbarufatti at INAF-OAB/IASFPA <>
L.M. McCauley (PSU), J.A. Kennea (PSU), B. Sbarufatti (INAF-OAB/PSU),
A.P. Beardmore (U. Leicester), J.P. Osborne (U. Leicester), V. D'Elia
(ASDC), A. D'ai (INAF-IASFPA), A. Maselli  (INAF-IASFPA) and P.A. Evans
(U. Leicester) report on behalf of the Swift-XRT team:

Swift-XRT has performed follow-up observations of the
Fermi/LAT-detected burst GRB 150902A (Arimoto et al. GCN Circ. 18228),
collecting 4.9 ks of Photon Counting (PC) mode data between T0+59.6 ks
and T0+78.6 ks. 

Two uncatalogued X-ray sources have been detected inside or close to
the Fermi/LAT error region, however none of them is above the RASS
limit or shows definitive signs of fading. Therefore, at the present
time we cannot identify which, if any, is the afterglow. Details of
these sources are given below:

Source 1:
  RA (J2000.0):  214.9797  =  14:19:55.13
  Dec (J2000.0): -69.3535  =  -69:21:12.6
  Error: 4.4 arcsec (radius, 90% conf.)
  Count-rate: 0.0116 +/- 0.0022 ct s^-1
  Flux: (5.16 +/- 0.98)e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)

Source 2:
  RA (J2000.0):  215.2707  =  14:21:4.97
  Dec (J2000.0): -69.4918  =  -69:29:30.3
  Error: 8.2 arcsec (radius, 90% conf.)
  Count-rate: (5.1 +/- 1.5)e-3 ct s^-1
  Flux: (2.07 +/- 0.62)e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)

The results of the XRT-team automatic analysis of the 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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