[vsnet-grb-info 16143] GRB 150203A iTelescope observation

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  17425
SUBJECT: GRB 150203A iTelescope observation
DATE:    15/02/07 11:36:49 GMT
FROM:    Takanori Sakamoto at AGU  <tsakamoto at phys.aoyama.ac.jp>

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

We observed the field of GRB 150203A detected by Swift (trigger #629578; 
Ukwatta et al., GCN Circ. 17377) with the iTelescope.Net (http://www.itelescope.net) 
T11 (0.50 m Plane Wave) telescope located at the New Mexico Skies Observatory (NM, USA). 
20 images of 60 sec exposures were taken in the R filter starting from February 3 
4:22:11 (UT) about 13.3 minutes after the trigger and stopped on February 3 4:47:29 (UT).  
We do not detect the optical afterglow both in the individual images and the stacked 
image at the enhanced X-ray afterglow position (Evans et al., GCN Circ. 17378).  
The estimated five sigma upper limit of the combined image (total exposure of 1200 sec) 
is ~18.9 using the USNO-B1 catalog.