GCN Circular 17004
Subject
GRB 141031A: Skynet PROMPT-CTIO Observations
Date
2014-10-31T19:20:02Z (10 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 141031A (Gompertz
et al., GCN 16995, Swift trigger=617110) with one 24" telescope (PROMPT
8; I band) and three 16" telescopes (PROMPT 3,4,5; B,R,I bands) of the
PROMPT array at CTIO, Chile.
Starting at 2014-10-31 07:19:46 UT and continuing until 08:53 UT
(t=79s-94m post-trigger), Skynet took a total of 196 exposures ranging
from 10s-160s each. We stacked subsets of these images to maximize the
S/N ratio, and detected no optical source in any band at the OT position
reported by GROND (Tanga et al., GCN 16996). Our 3-sigma limiting
magnitudes are:
==================================
tmid scope expos fil limit
==================================
52m PROMPT3 26x160s B >20.9
54m PROMPT4 24x160s R >21.6
53m PROMPT5 27x160s I >20.9
48m PROMPT8 45x80s I >20.9
==================================
Limiting magnitudes are in the Vega System, calibrated to 6 APASS stars
in the field. Magnitudes have not been corrected for line-of-sight
Milky Way dust extinction, with expected E(B-V)=0.15 (Schlafly &
Finkbeiner 2011).
No further Skynet observations are scheduled.