GCN Circular 15858
Subject
GRB 140215A: Continued Skynet PROMPT Observations of the Optical Afterglow
Date
2014-02-18T15:48:45Z (10 years ago)
From
Adam S. Trotter at UNC-Chapel Hill/PROMPT/Skynet <atrotter@physics.unc.edu>
A. LaCluyze, J. Haislip, D. Reichart, A. Trotter, S. Poshyachinda, W.
Rujopakarn, A. Foster, N. Frank, K. Ivarsen, J. Moore, M. Nysewander, R.
Beauchemin, T. Berger, M. Carroll, H. T. Cromartie, R. Egger, M.
Hinckle, A. Ireland, M. Maples, L. Scott, and J. A. Crain report:
Skynet continued observing the Swift-BAT localization of GRB 140215A
(Markwardt et al., GCN 15837, Swift trigger 586680) with six of the
PROMPT telescopes located at CTIO in Chile. LaCluyze et al. (GCN 15840)
described rapid-response observations of a fading optical afterglow
taken between ~1m and 6.5m after the burst in BVRI and luminance, and
presented a preliminary light curve calibrated to USNOB and NOMAD
catalog stars. A revised and recalibrated light curve, including
observations taken at t~20-24h, is at:
http://www.skynet.unc.edu/grb/grb140215a_2.png
In stacks of ~45x160s images from the second night, we do not detect the
afterglow with any degree of confidence (the I-band "detections" in the
light curve plot are most likely spurious.) The 3-sigma limiting
magnitudes are:
Band tmid Limit
I 21.9h >20.2
R 21.0h >20.5
V 21.8h >20.5
B 21.7h >20.3
Magnitudes are in the Vega system, and were calibrated to 4 APASS DR7
catalog stars in the field. They have not been corrected for
line-of-sight MW dust extinction corresponding to E(B-V)=0.09 (Schlegel
et al. 1998).
No further Skynet observations are scheduled.
