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GCN Circular 17452

GRB 150212A: Swift-XRT afterglow detection
2015-02-12T11:58:35Z (9 years ago)
Phil Evans at U of Leicester <>
P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team:

The XRT began observing the field at 11:03:12.7 UT, 353.7 seconds after
the BAT trigger. Due to passage of the spacecraft through the South 
Atlantic Anomaly, no XRT data were collected until T0+1805 s.

Using promptly downlinked data we find an uncatalogued
X-ray source located at RA, Dec 285.48092, 47.36602 which is equivalent
    RA(J2000)  = 19h 01m 55.42s
    Dec(J2000) = +47d 21' 57.7"
with an uncertainty of 4.3 arcseconds (radius, 90% containment). This
location is 176 arcseconds from the BAT onboard position, within the
BAT error circle. This position may be improved as more data are
received; the latest position is available at  We cannot determine whether the source is
fading at the present time.

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of 5.20
x 10^20 cm^-2 (Willingale et al. 2013).

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