GCN Circular 12809
Subject
GRB111228A :LOAO R-band Observations
Date
2012-01-06T02:50:13Z (12 years ago)
From
Yiseul Jeon at SNU/CEOU <ysjeon@astro.snu.ac.kr>
Minsung Jang, Myungshin Im, Yiseul Jeon (CEOU/Seoul National Univ.), and
Yuji Urata (NCU) on behalf of a larger collaboration
We continued our observation (Jeon et al. GCN 12791) of GRB 111228A
(Ukwatta et al., GCN 12737) in R-band with a 1 m telescope at Mt. Lemmon,
Arizona, US. Data were taken at 2011-12-31 UT and 2012-01-01 UT. For both
of them, we detected the afterglow in stacked R-band images.
We used a USNO B1 star near the afterglow, USNO-B1 1083-0199833 with
R=17.28 following Klotz et al. (GCN 12746) for our photometry calibration,
and current, rough estimates are given below.
Mid-time [UT] | Mid-time[Since BAT] | Exptime [sec] | R-magnitude
|
-------------------------------------------------------------------------------------------------------------
2011-12-31 08:40:25 | 64.92 hours | 300sec X 7 | 21.5 +/-
0.28 |
2012-01-01 11:19:52 | 91.58 hours | 300sec X 9 | 22.3 +/-
0.36 |
We thank the LOAO operator, J. Yoon for his help with these observations.