TITLE:   GCN CIRCULAR
NUMBER:  6037
SUBJECT: Possible GRB 070126: Swift/UVOT Upper Limit
DATE:    07/01/26 17:22:58 GMT
FROM:    Stefan Immler at NASA/GSFC  <immler@milkyway.gsfc.nasa.gov>

S. Immler (NASA/USRA) and L. Vetere (PSU) report on the behalf of the
Swift UVOT team:

The Swift/UVOT began observing the field of the possible burst GRB 070126
123 seconds after the BAT trigger (Vetere et al., GCN 6027).  No optical
afterglow candidate is detected in the BAT error circle within the first 
100 s
White exposure or in a coadded 590 s image, down to a limiting magnitude
of 21.0 (3-sigma).  The other UVOT filters only cover a small fraction
(around 25%) of the BAT error circle.

No correction has been made for the expected extinction corresponding to
E(B-V) = 0.05 mag (Schlegel et al. 1998).