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GCN Circular 17634

GRB 150323B: Swift-XRT observations
2015-03-24T11:07:30Z (9 years ago)
Phil Evans at U of Leicester <>
P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), M. de Pasquale (INAF-IASFPA),
D.N. Burrows (PSU), J.A. Kennea (PSU), B. Sbarufatti (INAF-OAB/PSU),
J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), C. Pagani (U.
Leicester) and P.A. Evans (U. Leicester) report on behalf of the
Swift-XRT team:

Swift-XRT has performed follow-up observations of the
Swift/BAT-detected burst GRB 150323B (Cummings et al. GCN Circ. 17619),
collecting 4.6 ks of Photon Counting (PC) mode data between T0+40.4 ks
and T0+63.2 ks. 

Two uncatalogued X-ray sources have been detected inside or close to
the Swift/BAT 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):  260.4534  =  17:21:48.83
  Dec (J2000.0): +38.3179  =  +38:19:04.6
  Error: 4.3 arcsec (radius, 90% conf.)
  Count-rate: 0.0103 +/- 0.0018 ct s^-1
  Flux: (4.62 +/- 0.80)e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)

Source 2:
  RA (J2000.0):  260.4598  =  17:21:50.35
  Dec (J2000.0): +38.2829  =  +38:16:58.5
  Error: 6.6 arcsec (radius, 90% conf.)
  Count-rate: (2.3 +/- 1.0)e-3 ct s^-1
  Flux: (9.2 +/- 4.1)e-14 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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