GCN Circular 15646
Subject
GRB 131231A: MDM afterglow observation
Date
2014-01-01T08:13:16Z (10 years ago)
From
Jules Halpern at Columbia U. <jules@astro.columbia.edu>
J. P. Halpern (Columbia U.) reports:
I observed the afterglow of GRB 131231A (Sonbas et al., GCN 15640;
Xu et al., GCN 15641) using the 1.3m McGraw-Hill telescope of the
MDM Observatory on 2014 January 1, from 01:40 to 03:18 UT.
Nineteen 5-minute exposures were obtained in the R-band.
Conditions were photometric, and the Landolt standard-star field
around PG0231+051 was used for calibration. The afterglow magnitudes
measured for the first and last exposures of the sequence are:
--------------------------------
Jan 1 UT t-t0(hr) R +/-
--------------------------------
01:40 20.92 18.48 0.02
03:18 22.55 18.61 0.02
--------------------------------
The following stars in field were calibrated, and can be used for
comparison:
-----------------------------------------
Star R.A.(2000) Decl.(2000) R
-----------------------------------------
A 00 42 30.4 -01 36 13 16.07
B 00 42 11.7 -01 37 29 17.95
C 00 42 15.9 -01 39 08 17.92
D 00 42 20.0 -01 41 53 17.22
E 00 42 28.8 -01 40 16 17.96
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