GCN Circular 14840
Subject
GRB 130606A - Liverpool Telescope and Faulkes Telescope North optical observations
Date
2013-06-09T21:43:42Z (11 years ago)
From
Francisco Virgili at Liverpool John Moores U <fjv@astro.livjm.ac.uk>
F.J. Virgili, C.G. Mundell (LJMU), A. Melandri (INAF-OAB), and A. Gomboc
(U. Ljubljana) report:
Observations of GRB 130606A (Ukwatta et al., GCN 14781) with the 2-m
robotic Liverpool Telescope automatically performed between 48 and 80
minutes after the GRB trigger confirms a detection of the afterglow in
the r'-band with magnitude
r' = 21.9 � 0.29 at 49.95 minutes
consistent with reported values at similar epochs (Xu et al. 14783) and
dimmer than times around 100 minutes post trigger (Leonini et al., GCN
14791; Masi et al., GCN 14789; Sonbas et al., GCN 14797), possibly
indicating mild re-brightening. This detection clarifies that the
afterglow has not yet dropped out of the r'-band at the times coincident
with our i' and z' band detections (Virgili et al., GCN 14785) and
continues to be detected until at least 6.4 hrs after the initial
trigger (Afonso et al., GCN 14807).
In addition, the 2-m Faulkes Telescope North and Liverpool Telescope
performed late-time follow up observations, resulting in a 3-sigma
upper-limit of
r' > 23.4 at 849.73 min (14.16 hr post-trigger; FTN)
r' > 24 at 1683.67 minutes (= 28.06 hr; LT)
and an additional i'-band detection of
i' = 23.76 � 0.22 @ 28.60 hr (= 1716.51 minutes; LT),
in a co-added series of 6x300s exposures, which are consistent with
values reported by Trotter et al. (GCN 14815) and Butler et al. (GCN
14824). FTN images have been acquired with the R-Bessell filter and
calibrated against nearby SDSS catalogue stars.