[vsnet-grb-info 16148] GRB 150202B: Swift/XRT afterglow confirmation

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  17429
SUBJECT: GRB 150202B: Swift/XRT afterglow confirmation
DATE:    15/02/09 19:09:10 GMT
FROM:    Boris Sbarufatti at INAF-OAB/IASFPA  <boris.sbarufatti at brera.inaf.it>

B. Sbarufatti (INAF-OAB/PSU), P.A. Evans (U. Leicester) and M. H. Siegel (PSU) report on behalf of the Swift team.

Swift took a second epoch of data for the LAT/IPN GRB 150202B (Axelsson et al. GCN Circ. 17385, Hurley et al. GCN Circ. 17398) between T+515.2 ks and T+516.4 ks, with a 1.2 ks exposure time. 
Of the two unknown sources reported by Sbarufatti et al. (GCN 17405), Source #2 is still detected at a level of 8.4E-3 counts/s (3.7E-13 erg cm^-2 s^-2), comparable with the previous observation, while Source #1 has faded below detection, to a 3-sigma upper limit of 4.8E-3 counts/s (1.6E-13 erg cm^-2 s^-1).
We therefore confirm that Source #1 is the X-ray afterglow of GRB 150202B.

The results of the XRT-team automatic analysis of the likely afterglow
are at http://www.swift.ac.uk/xrt_products/TILED_GRB00039/index_1.php.
The results of the full analysis of the XRT observations are available
at http://www.swift.ac.uk/xrt_products/TILED_GRB00039/.

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