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GCN Circular 18423

GRB 151004A: Swift-XRT follow-up observations
2015-10-16T13:25:03Z (9 years ago)
Claudio Pagani at U of Leicester <>
C. Pagani, K. L. Page, P. A. Evans (U. Leicester) and S. B. Cenko (GSFC) 
report on behalf of the Swift-XRT team:

A second epoch of XRT data was collected on the field of the Swift 
Trigger 657564 / GRB 151004A (Cenko et al., GCN Circ. 18389) on 2015 
October 15. The observations consist of 7.7 ks of PC mode data, from 
T0+885 ks to T0+932 ks.

The candidate X-ray source reported in Barthelmy et al., GCN Circ. 
18396, originally detected at a count rate of 4.8 (+/- 1.14) x 10^-3 
cnts/sec (0.3-10 keV) is not detected in this second epoch of 
observations, with a 3 sigma upper limit of 1.5 x 10^-3 cnts/sec (0.3-10 
keV). The fading confirms that this is the X-ray afterglow of the Swift 
Trigger 657564 / GRB 151004A.

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