A. Melandri (INAF-OAB), B. Sbarufatti (INAF-OAB/PSU), M.C. Stroh (PSU),
D.N. Burrows (PSU), J.A. Kennea (PSU), K.L. Page (U. Leicester), C.
Pagani (U. Leicester), A.P. Beardmore (U. Leicester), P. D'Avanzo
(INAF-OAB) and P.A. Evans (U. Leicester) report on behalf of the
Swift-XRT has performed follow-up observations of the
Swift/BAT-detected burst GRB 150204A (Cummings et al. GCN Circ. 17404),
collecting 4.4 ks of Photon Counting (PC) mode data between T0+51.2 ks
and T0+63.6 ks.
One uncatalogued X-ray source has been detected inside or close to the
Swift/BAT error region, 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:
RA (J2000.0): 160.2373 = 10:40:56.94
Dec (J2000.0): -64.0387 = -64:02:19.4
Error: 4.8 arcsec (radius, 90% conf.)
Count-rate: (8.9 +/- 1.8)e-3 ct s^-1
Flux: (3.69 +/- 0.75)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.