TITLE:   GCN CIRCULAR
NUMBER:  14319
SUBJECT: GRB130313A: GTC early optical limits
DATE:    13/03/16 08:10:39 GMT
FROM:    Alberto Castro-Tirado at Inst.de Astro. de Andalucia  <ajct@iaa.es>

J. Gorosabel (UPV/EHU-IAA/CSIC), J.C. Tello, R. Sánchez-Ramírez, M.
Jelinek, A. J. Castro-Tirado (IAA-CSIC Granada), report on behalf of a
larger
collaboration:

"We have observed the field of the short duration GRB 130313A (Gompertz et
al., GCN 14293) using the 10.4m GTC in Sloan r,i and z filters with a
seeing of ~1.3", however at an airmass of ~1.4 and with cirruses across
the field. The combined exposure of 12x70 s images with a Sloan i filter
taken starting 02:54:47UT and ending 03:14:58UT (10.7 - 11.1 hours after
the burst) shows no afterglow candidate within the refined XRT uncertainty
circle (Osborne et al., GCN 14300) down to a magnitude of i > 23.5 when
compared to the SDSS Photometric Catalog, Release 6."