GCN Circular 7062

Subject

GRB 071112C: Optical and NIR afterglows observed with KANATA

Event

Date

2007-11-12T20:07:47Z (18 years ago)

From

Makoto Uemura at Hiroshima U <uemuram@hiroshima-u.ac.jp>

M. Uemura, M. Sasada, A. Arai, and T. Uehara (Hiroshima Univ.), 
report on behalf of the KANATA GRB team:

  We performed optical-NIR observations of the field of 
GRB 071112C (GCN Circ. 7059Loading...
 
 ) with TRISPEC attached to 
the "KANATA" 1.5-m telescope.  

  We found a fading object at the position of the optical 
afterglow detected with UVOT.  
Our preliminary results are below:

time(UT)       mag.              exposure_time
Nov. 2007                        (sec)
12.77880       17.76 +/- 0.14 V  30sec * 10
12.77911       16.39 +/- 0.22 J  25sec * 9
12.78674       18.66 +/- 0.20 V  123sec * 5
12.78672       17.16 +/- 0.17 J  120sec * 5

Comparison star: 
V-band: GSC2.3 02:36:55.72 +28:21:03.7 V=14.15
J-band: 2MASS  02:36:55.72 +28:21:03.7 J=12.674
 
The large errors of magnitudes are due to the rapidly 
fading trend of the afterglow. 
Further observation and analysis are ongoing.