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GCN Circular 20006

GRB 160925A: Kottamia R-band observation
2016-10-06T23:05:13Z (8 years ago)
Gamal B. Ali at NRIAG <>
G. B. Ali, Y. Hendy, A. Takey, N. Essam, and A. Essam (NRIAG, Egypt) 
report on behalf of the Kottamia collaboration:

We observed the field of the Fermi GRB 160925A (trigger #496473540) with
the 1.88m telescope of the KAO (Kottamia Astronomical Observatory),
Egypt. The observation was performed in the Rc-band at the Newtonian
camera (F4.8) and started at 2016-09-29 T19:58:17 UT (~4.08 day after
the burst). 

We obtained several exposures in the Rc-band each one with 300s exposure
time.  We clearly detected the optical transient (Lipunov et al., GCN
19938; Guidorzi et al., GCN  19939). 

The following accurate photometry is obtained for the transient: 

UT (Start)                            Rc           error*   

2016-09-29T19:58:17       17.260   0.011 

2016-09-29T20:03:31       17.232   0.011 

2016-09-29T20:08:42       17.252   0.012 

2016-09-29T20:13:53       17.326   0.013 

2016-09-29T20:19:04       17.267   0.012 

2016-09-29T20:24:15       17.223   0.011 

2016-09-29T20:29:26       17.305   0.011 

2016-09-29T20:34:37       17.281   0.012 

2016-09-29T20:39:48       17.239   0.011 


(*) Poisson noise error only. 

The Photometric calibration is based on nearby USNO-B1.0 stars

USNO-B1.0        R2 

0750-0813981 13.69 

0750-0813991 14.20 

0750-0813958 14.93 

0750-0813917 15.62

[GCN OPS NOTE(08oct16): Per author's request, the signature block and the appended
copy of the 19947 circular have been removed.]
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