[vsnet-grb-info 14577] GRB 140226A / iPTF14yb: Swift-XRT confirms a fading X-ray source

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  15891
SUBJECT: GRB 140226A / iPTF14yb: Swift-XRT confirms a fading X-ray source
DATE:    14/02/28 15:11:10 GMT
FROM:    Andy Beardmore at U Leicester  <ab271 at leicester.ac.uk>

A.P. Beardmore (U. Leicester) reports on behalf of the Swift-XRT team:

The Swift-XRT has continued to observe the source GRB 140226A /
iPTF14yb (Cenko et al., GCN Circ. 15883; Cucchiara et al., GCN
Circ. 15886; Varela et al., GCN Circ. 15887; Hurley et al., GCN
Circ. 15888) and has now accumulated 9.1ks of data in Photon Counting
(PC) mode. The X-ray light curve shows that the source announced by
Beardmore et al. (GCN Circ. 15884) has faded, with a powerlaw decay
index of 1.47 +0.29 -0.25 (with respect to the Konus-Wind T0;
Golenetskii et al., GCN Circ. 15889).

Taken together with the fading optical source and IPN localisation,
the decaying X-ray source confirms the GRB origin of the object.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00033157.