GCN Circular 16300
Subject
GRB 140518A: P60 i-/z-band detections
Date
2014-05-18T12:22:01Z (10 years ago)
From
Daniel Perley at Caltech <dperley@astro.caltech.edu>
D. A. Perley (Caltech) reports on behalf of a larger collaboration
The Palomar 60-inch telescope responded automatically to the Swift
trigger for GRB 140518A (Melandri et al., GCN 16298) and began a
repeating cycle of 60-second exposures in r, i, and z-band observations
at 09:22:28 UT, 4.70 minutes after the burst.
We weakly detect the afterglow reported by Zheng et al. (GCN 16299) in
the i and z filters, but not in r-band. Only marginal detections are
evident in any individual exposure in any filter, but a stack of the
first six exposures in each band gives magnitudes (calibrated relative
to SDSS) of:
r > 20.31 (2 sigma)
i = 19.03 +/- 0.16
z = 18.20 +/- 0.17
at a mid-time of approximately 16 minutes after the burst.