[vsnet-grb-info 14532] GRB 140215A: ISON-NM optical observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  15846
SUBJECT: GRB 140215A: ISON-NM optical observations
DATE:    14/02/15 20:32:45 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen at iki.rssi.ru>

L. Elenin (KIAM),  A. Volnova (IKI), I. Molotov (KIAM), A. Pozanenko (IKI) 
report on behalf of larger GRB  follow-up collaboration:

We observed of  the field of  the Swift GRB 140215A (Markwardt et al.,  GCN 
15837)  with 0.4-m telescope of ISON-NM observatory starting on Feb., 15 
(UT)  04:08:22, i.e 72 seconds after  Swift burst trigger.  We took 35 
unfiltered images of 30 s exposures. We clearly detect the bright optical 
afterglow of GRB 140215A (Markwardt et al.,  GCN 15837; Cenko et al., GCN 
15838) in each separate image.  Coordinates of the optical afterglow 
(J2000) 06 56 35.83 +41 47 11.4 (uncertainties of 0.5 arcsec) coincide with 
OT coordinates (Markwardt et al.,  GCN 15837). Preliminary photometry  is 
following:

UT mid,      T0+        Filter    Exposure,  OT,    err OT
                  mid                   s
04:08:22      0.00101 none    30            13.60   0.03
04:37:01      0.02090 none    30            16.46   0.20

The photometry  is based  on USNO-B1.0 nearby stars:

N USNO-B1.0id RA                Dec           R2
1 1318-0183851 06:56:13.01 +41:49:29.2 12.37
2 1317-0181981 06:56:37.13 +41:44:34.4 14.39
3 1317-0181986 06:56:38.48 +41:44:12.8 14.50

The power law index of  ~-1.2 of  our light curve starting from 0.0025 days 
and up to the end of our observations coincides with the index reported by 
Perley and Cenko  (GCN 15844).