[vsnet-grb-info 13576] GRB 130615A: TAROT La Silla observatory optical observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  14905
SUBJECT: GRB 130615A: TAROT La Silla observatory optical observations
DATE:    13/06/15 22:01:29 GMT
FROM:    Alain Klotz at IRAP-CNRS-OMP  <Alain.Klotz at free.fr>

Klotz A. (IRAP-CNRS-OMP), Gendre B. (IRAP-CNRS-OMP),
Boer M., Siellez K., Dereli H., Bardho O. (UNS-CNRS-OCA),
Atteia J.L. (IRAP-CNRS-OMP) report:

We imaged the field of GRB 130615A detected by SWIFT
(trigger 558271) with the TAROT robotic telescope (D=25cm)
located at the European Southern Observatory,
La Silla observatory, Chile.

The observations started 91.8s after the GRB trigger
(14.2s after the notice). The elevation of the field decreased from
36 degrees above horizon and weather conditions
were good.

The first image is trailed with a duration of 60.0s
(see the description in Klotz et al., 2006, A&A 451, L39).
We do not detect the afterglow candidate mentioned by
Elliott et al. (GCNC 14898) with a limiting magnitude of:
t0+91.8s to t0+151.8s : Rlim = 16.4

The second image is 30.0s exposure in tracking mode,
the afterglow is not seen:
t0+165.4s to t0+195.4s : Rlim = 18.0

We co-added a series of exposures,
the afterglow is not seen:
t0+479s to t0+992s : Rlim = 19.3

Magnitudes were estimated with the nearby USNO-B1 stars
and are not corrected for galactic dust extinction.