[vsnet-grb-info 13227] GRB 130504A: IAC80 optical candidate

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  14564
SUBJECT: GRB 130504A: IAC80 optical candidate
DATE:    13/05/05 08:38:59 GMT
FROM:    Javier Gorosabel at IAA-CSIC  <jgu at iaa.es>

J. Gorosabel (IAA-CSIC/UPV-EHU), A. de Ugarte Postigo (IAA-CSIC/DARK-NBI),
J.C. Tello (IAA-CSIC),  A.J. Castro-Tirado (IAA-CSIC), J. Cepa (IAC), D.
Jimenez-Mejias (IAC),  J.L. Doreste Caballero (HGT), D. Hernandez Ojados
(SECAT), R. Sanchez-Ramirez (IAA-CSIC),  report on behalf of a larger
collaboration:

We observed the GRB 130504A field (BAT trigger 555096; Cummings et al. GCN
14551) with the 0.82m IAC80 telescope. The data were acquired in the
I-band. The observations started at 02:22:30.6 UT (~17 min post burst) and
lasted ~1.5 hours.

An object, coincident with the enhanced XRT position (D'Avanzo et al.
14558), shows a clear fading in our images. The optical candidate is
placed at RA(J2000)=18:09:49.44, DEC(J2000)=-16:18:48.0 with a Vega
magnitude of I=18.1 (against USNO B1.0) in our first images.