[vsnet-grb-info 17678] GRB 160227A: AROMA-N Optical Observation

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  19115
SUBJECT: GRB 160227A: AROMA-N Optical Observation
DATE:    16/02/29 13:07:42 GMT
FROM:    Takanori Sakamoto at AGU  <tsakamoto at phys.aoyama.ac.jp>

Y. Kitaoka, T. Sakamoto, A. Yoshida (AGU)

We observed the field of GRB 160227A detected by Swift (trigger #676423; 
Siegel et al., GCN Circ. 19098) with the 12-inch AGU Robotic Optical 
Monitor for Astrophysical object - Narrow (AROMA-N) located at 
the Sagamihara campus of Aoyama Gakuin University.  

10 images of 60 sec exposures and 5 images of 180 sec exposures 
were taken in the R filter starting from February 27 19:36:28 (UT) 
about 260 seconds after the trigger and stopped on February 27 20:02:05 (UT).  
Because the target was a low elevation (44.4 deg at the start time) and 
the telescope was slightly out of focus, the quality of the obtained images 
was not ideal.  We do not detect the optical afterglow both in the individual 
images and the stacked image.  The estimated five sigma upper limit of 
the combined image (total exposure of 1500 sec) is ~16.4 mag using 
the USNO-B1 catalog.