[vsnet-grb-info 9712] GRB 100901A: 1.5m OSN BVRI-band observations.

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  11180
SUBJECT: GRB 100901A: 1.5m OSN BVRI-band observations.
DATE:    10/09/02 19:34:45 GMT
FROM:    Juan Carlos Tello at IAA-CSIC  <jtello at iaa.es>

R. Sánchez-Ramírez, J.C. Tello, A. Sota, J. Gorosabel, A.J. Castro-Tirado
(IAA-CSIC, Granada), report on behalf of a larger collaboration:

"We have taken several series of BVRI-band images of the  Swift GRB 100901A
(Immler et  al. GCNC  11159) optical afterglow  (Guidorzi et  al. GCNC
11160) with the  1.5m  telescope at  Observatorio  de Sierra  Nevada, Spain.
  The  afterglow is  well  detected  in  the four  bands,  with preliminary
 average magnitudes (calibrated against  USNO  B1.0  and GSC  3.2 stars) of
 B~18.0 (Sep  2.021 UT), V~17.4  (Sep 2.035 UT),  R~17.3 (Sep 2.003 UT) and
I~17.3 (Sep 2.049 UT)."