Skip to main content
Testing. You are viewing the public testing version of GCN. For the production version, go to
New Announcement Feature, Code of Conduct, Circular Revisions. See news and announcements

GCN Circular 29092

GRB 201214A: Swift-XRT afterglow detection
2020-12-19T19:28:30Z (3 years ago)
Aaron Tohuvavohu at U Toronto <>
J.A. Kennea (PSU), A. Tohuvavohu (U. Toronto), J.P. Osborne (U.
Leicester), K.L. Page (U. Leicester), T. Sbarrato (INAF-OAB), P.
D'Avanzo (INAF-OAB), M.G. Bernardini (INAF-OAB), B. Sbarufatti (PSU)
and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team:

Swift-XRT has conducted further observations of the field of the
INTEGRAL-detected burst GRB 201214A (Mereghetti et al. GCN Circ.
29037). The observations now extend from T0+5.3 ks to T0+378.1 ks. The
source previously reported by Kennea et al. (GCN Circ. 29048), "Source
2", is fading with 3-sigma significance, and is therefore likely the
GRB afterglow. Using 2671 s of PC mode data and 4 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 = 170.92446,
+33.86930 which is equivalent to:

RA (J2000): 11h 23m 41.87s
Dec(J2000): +33d 52' 09.5"

with an uncertainty of 2.2 arcsec (radius, 90% confidence). This
position is 36 arcsec from the INTEGRAL position.  The source is fading
with alpha >0.6.

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.7 (+0.9, -0.7). The
best-fitting absorption column is  1.9 (+2.2, -1.6) x 10^21 cm^-2, in
excess of the Galactic value of 2.4 x 10^20 cm^-2 (Willingale et al.
2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion
factor deduced from this spectrum  is 2.6 x 10^-11 (2.6 x 10^-11) erg
cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:	     1.9 (+2.2, -1.6) x 10^21 cm^-2
Galactic foreground: 2.4 x 10^20 cm^-2
Excess significance: 1.8 sigma
Photon index:	     2.7 (+0.9, -0.7)

The results of the XRT-team automatic analysis of the likely afterglow
are at
The results of the full analysis of the XRT observations are available

This circular is an official product of the Swift-XRT team.
Looking for U.S. government information and services? Visit