GCN Circular 14697
Subject
GRB 130521A: Skynet/PROMPT observations
Date
2013-05-23T02:23:02Z (12 years ago)
From
Adam S. Trotter at UNC-Chapel Hill/PROMPT/Skynet <atrotter@physics.unc.edu>
D. James, C. Foster, P. Taylor, M. Carroll, A. Trotter, D. Reichart, A.
LaCluyze, J. Haislip, T. Berger, H. T. Cromartie, R. Egger, A. Foster,
N. Frank, K. Ivarsen, M. Maples, J. Moore, M. Nysewander, E. Speckhard,
and J. A. Crain report
Skynet observed the Swift/BAT localization of GRB 130521A (Pagani et
al., GCN 14691, Swift trigger #556344) with four 16" telescopes of the
PROMPT array at CTIO, Chile. Starting at 2013-05-21, 22:49:16 UT and
continuing until 23:01:04 UT (t=49.2s-11.8m post-trigger), it took 66
exposures in the BVRI bands. We did not detect a fading afterglow within
the 3 arcmin radius of the Swift/BAT error circle, which was centered on
RA 05h50m14.2s, Dec +14d27m08.6s (J2000.0).
A plot of the 3-sigma limiting magnitudes in each exposure, calibrated
to six USNO-B1/NOMAD stars in the field, is here:
http://skynet.unc.edu/grb/grb130521a.png
We stacked all the images in each band and obtained 3-sigma limiting
magnitudes on any afterglow of:
Filter B V R I
Mag >18.29 >18.53 >18.13 >17.07
Magnitudes are Vega magnitudes, and have not been corrected for the
expected line-of-sight Milky Way dust extinction E(B-V)=0.38 (Schlegel
et al. 1998).
No further Skynet observations are scheduled.