[vsnet-grb-info 8834] GRB 100115A: SARA Astrometry

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  10332
SUBJECT: GRB 100115A: SARA Astrometry
DATE:    10/01/17 04:56:47 GMT
FROM:    Alexander Kann at TLS Tautenburg  <kann at tls-tautenburg.de>

D. Alexander Kann (TLS Tautenburg), Adria C. Updike and Dieter H. Hartmann 
(Clemson University) report:

We performed astrometry (against the USNO-B1.0 catalog) on the image of 
the field of GRB 100115A (Cummings et al., GCN 10325) taken by the 0.9m 
SARA observatory at KPNO, which revealed a possible afterglow candidate 
(Updike et al., GCN 10328).

For this object, we derive a position of (conservative error 1"):

RA (J2000):    00:13:28.05
Dec. (J2000): -00:49:32.4

in full agreement with the position given for Object "A" by Jelinek et al. 
(GCN 10331), and possibly closer to (or identical with) the brighter 
southwest component of Object "A".

Given the lack of photometric information in Jelinek et al. (GCN 10331) we 
cannot confirm if the SARA candidate has faded significantly, but note 
that, in the SARA image, the afterglow candidate is about as bright as the 
star to the southwest at RA (J2000): 00:13:27.20, Dec. (J2000): -00:49:42.4, and it 
seems to be much fainter than this source (note the different filters, 
though) in the Jelinek finding chart.

This message may be cited.