GCN Circular 17210
Subject
GRB 141221A: Skynet PROMPT-CTIO observations of the optical afterglow
Date
2014-12-21T15:16:10Z (9 years ago)
From
Adam S. Trotter at UNC-Chapel Hill/PROMPT/Skynet <atrotter@physics.unc.edu>
A. Trotter, J. Haislip, D. Reichart, A. Aji, R. Beauchemin, T. Berger,
A. Dow, A. Foster, N. Frank, M. Hinckle, K. Ivarsen, A. LaCluyze, M.
Maples, J. Moore, M. Nysewander, C. Salemi, L. Zbinden, and J. A. Crain
report:
Skynet observed the Swift BAT/XRT localization of GRB 141221A (Sonbas et
al., GCN 17206, Swift trigger=622006) with two 14" telescopes of the
PROMPT array at Cerro Tololo, Chile. Starting at 2014-12-21 08:07:56 UT
and continuing until 08:35 UT (t=45s-28m post-trigger), Skynet took a
total of 44 exposures ranging from 5s to 160s in the V and I bands. We
clearly detect the optical afterglow (Covino, GCN 17208, Guidorzi et
al., GCN 17209) with a rising light curve prior to t=2min, where it
peaks at I=14.8.
A preliminary light curve is at:
http://www.skynet.unc.edu/grb/grb141221a.png
Magnitudes are in the Vega System, calibrated to 3 APASS stars in the
field. Magnitudes have not been corrected for line-of-sight Milky Way
dust extinction, with expected E(B-V)=0.024 (Schlafly & Finkbeiner 2011).
Skynet observations will continue.
