TITLE:   GCN CIRCULAR
NUMBER:  4389
SUBJECT: GRB 051221A: Chandra Afterglow Position
DATE:    05/12/23 07:14:20 GMT
FROM:    Dirk Grupe at PSU/Swift-XRT  <grupe@astro.psu.edu>

GRB 051221A: Chandra Afterglow Position

D. Grupe (PSU), D. N. Burrows (PSU), and S. Patel (NASA/MSFC) report on 
behalf of a larger collaboration:

We executed a Chandra ToO observation of GRB 051221A beginning at 2005-12-22
13:55:20 UT  (130 ks after the burst) and lasting for 30.2 ks.  A fading 
X-ray source was found within the XRT error circle (Burrows et al., GCN 
4366) at

   RA(J2000)  =  21:54:48.626
   Dec(J2000) = +16:53:27.16

Chandra positions have typical uncertainties of 0.5 arcseconds 
(radius).  This
position is 0.55 arcseconds from the optical counterpart identified by 
Bloom et al. (GCN 4368)
and 0.34 arcseconds from the position reported by Berger (GCN 4369)