GCN Circular 4770
Subject
GRB060213: Swift XRT observations and possible afterglow candidate
Date
2006-02-17T18:53:47Z (19 years ago)
From
David Morris at PSU/Swift-XRT <morris@astro.psu.edu>
D. C. Morris (PSU), J. A. Kennea (PSU), C. Pagani (PSU) report on behalf
of the Swift XRT Team:
Swift responded to the IPN trigger of GRB060213 (Pal'shin et al., GCN
4762) and has observed the entire IPN error polygon with the XRT during
observations spanning T+174ks to T+285ks. We have analyzed the entire
XRT ground-linked dataset. In 9ks of data we find a single, faint,
uncatalogued source within the IPN localization at the following position:
RA(J2000): 09 26 24.5
Dec(J2000): -09 06 58.5
with an estimated uncertainty of 10 arcseconds (90% containment). The
source is detected at 2.6 sigma and the flux at T+3days from the
GRB060213 trigger is 2e-13+/-5e-14 ergs/cm2/s. We note that this source
does not show evidence of fading during the 1.25 day window of XRT
observations and appears slightly extended to the east, which both
suggest the possibility that it may be a faint serendipitous object and
not the GRB afterglow. However, we also note that it is not uncommon for
a GRB afterglow at this late stage to have a fairly flat lightcurve
consistent with the observed counting statistics, and we therefore
cannot rule this out as an afterglow candidate. Further observations
will be required to determine conclusively whether this source is fading.
No other point source is detected above a limiting flux of 1e-13
ergs/cm2/s anywhere in the IPN localization, or in the broader
surrounding region covered by the XRT field of view during the
observations.
No further observations are planned for at least the next four days;
however, we tentatively plan further observations in approximately a
week to determine whether the source is fading.
The XRT image of the field can be viewed at
http://www.swift.psu.edu/images/GRB060213.jpg
This circular is an official product of the Swift XRT Team.