[vsnet-grb-info 15265] GRB 140709B: OSN optical limit

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  16557
SUBJECT: GRB 140709B: OSN optical limit
DATE:    14/07/09 22:47:34 GMT
FROM:    Alberto Castro-Tirado at Inst.de Astro. de Andalucia  <ajct at iaa.es>

A. Sota (IAA-CSIC), J. Gorosabel (IAA-CSIC, UPV-EHU) and A. J.
Castro-Tirado (IAA-CSIC, ISA-UMA), on behalf of a larger collaboration,
report:

Following the detection of GRB 140709B by Swift (Swenson et al. GCNC
16551), we have taken I-band frames with the 1.5m OSN telescope at
Observatorio de Sierra Nevada (Granada, Spain) starting at 20:45 UT (5.5 h
post burst) at high airmass. Within the enhanced XRT position (Goad et al.
GCNC 16556) we find no credible counterpart down to the DSS-2 limiting
magnitude when all the images are co-added (10 x 150s). Near-infrared
imaging is encouraged.