[vsnet-grb-info 13992] GRB 131004A: Liverpool Telescope optical afterglow observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  15306
SUBJECT: GRB 131004A: Liverpool Telescope optical afterglow observations
DATE:    13/10/05 00:06:15 GMT
FROM:    Drejc Kopac at Math Phys U,Slovenia  <drejc.kopac at fmf.uni-lj.si>

D. Kopac (U. Ljubljana), R. J. Smith (LJMU), C. G. Mundell (LJMU), N. R.
Tanvir (U. Leicester) and A. Gomboc (U. Ljubljana), on behalf of a large
collaboration report:

The 2-m Liverpool Telescope automatically began observing the field of GRB
131004A (Hagen et al., GCN 15303). We detect the optical afterglow in the
position consistent with the NOT (Xu et al., GCN 15304) and TNG (Malesani
et al., GCN 15305). Our preliminary photometry yields:

Mid time from   Exp    Filter   Magnitude
trigger (min)   (sec)
-------------------------------------------
85.1            300    i'       20.2 +- 0.1
111.3           300    i'       20.6 +- 0.1
-------------------------------------------

The magnitudes are calibrated agains I magnitudes of nearby USNO-B1.0
stars and are not corrected for the Galactic extinction.