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GCN Circular 16811

GRB 140909A: Swift-XRT observations
2014-09-10T07:13:30Z (10 years ago)
Claudio Pagani at U of Leicester <>
C. Pagani, K.L. Page and P.A. Evans (U. Leicester) report on behalf of
the Swift-XRT team:

We have analysed 5.0 ks of XRT data for the Swift/BAT-detected burst:
GRB 140909A,  from 44.0 ks to 56.5 ks after the  Swift/BAT trigger. The
data are entirely in Photon Counting (PC) mode.  An X-ray source is
detected within the Swift/BAT error circle. Using 1945 s of PC mode
data and 1 UVOT images, we find an enhanced XRT position (using the
XRT-UVOT alignment and matching UVOT field sources to the USNO-B1
catalogue): RA, Dec = 193.61156, +63.51677 which is equivalent to:

RA (J2000): 12h 54m 26.78s
Dec(J2000): +63d 31' 00.4"

with an uncertainty of 7.2 arcsec (radius, 90% confidence). This
position is 92 arcsec from the Swift/BAT position.  The source has a
mean count rate of 6.9e-03 ct/sec; we cannot determine at the present
time whether it is fading.

The results of the XRT-team automatic analysis are available at

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