[vsnet-grb-info 15021] GRB 140521A: AROMA-N Optical Observation

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  16315
SUBJECT: GRB 140521A: AROMA-N Optical Observation
DATE:    14/05/22 10:31:49 GMT
FROM:    Takanori Sakamoto at AGU  <tsakamoto at phys.aoyama.ac.jp>

D. Kawamura, T. Sakamoto, I. Takahashi, A. Yoshida (AGU)

We observed the field of GRB 140521A detected by Swift (trigger #599546; 
Troja et al., GCN Circ. 16311) with the 12-inch AGU Robotic Optical 
Monitor for Astrophysical object - Narrow (AROMA-N) located at the Sagamihara 
campus of Aoyama Gakuin University.  

15 images of 60 sec exposures were taken in the R filter starting from 
May 21 17:36:17 (UT) about 119 sec after the trigger 
(104 sec after the BAT position notice) and stopped on May 21 18:03:04 (UT).  
We do not detect the optical afterglow both in the individual images and 
the stacked image inside the BAT flight position (Troja, et al., GCN #16311).  
The estimated five sigma upper limit of the combined image (total exposure of  900 sec) 
is ~17.2 mag using the USNO-B1 catalog.