TITLE:   GCN CIRCULAR
NUMBER:  14301
SUBJECT: GRB 130313A: NOT optical upper limit
DATE:    13/03/14 05:00:30 GMT
FROM:    Dong Xu at DARK/NBI  <dong.dark@gmail.com>

D. Xu (DARK/NBI), S. Schulze  (PUC and MCSS), N. R. Tanvir (U.
Leicester), H. Dahle, N. Groeneboom (U. Oslo), and J. P. U. Fynbo (DARK/NBI), report
on behalf of a larger collaboration:

We imaged the field of GRB 130313A (Gompertz et al., GCN 14293) using
the 2.5m Nordic Optical Telescope (NOT) equipped with the ALFOSC
instrument, located on La Palma, Canary Islands. Observations started
at 02:16:32 UT on 2013-03-14 (i.e., 10.139 hr after the BAT trigger)
and 12x300s SDSS_i-band images were obtained in good seeing of ~0.7".

No object was found within the refined XRT error circle (Osborne et
al., GCN 14300) in the stacked image, down to a limit of i>23.4 mag,
calibrated with nearby SDSS stars.

[GCN OPS NOTE(14mar13): Per author's request, NG was added to the author list.]