[vsnet-grb-info 12050] GRB 120711A: REM NIR early time detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  13439
SUBJECT: GRB 120711A: REM NIR early time detection
DATE:    12/07/11 11:31:46 GMT
FROM:    Stefano Covino at Brera Astronomical Observatory  <stefano.covino at gmail.com>

D. Fugazza, S. Covino, A. Rossi on behalf of the REM team report:


We imaged the field of GRB120711A (Gotz et al., GCN 13434 and Bozzo et al., GCN 13435) with the NIR camera (the optical camera is at present under maintenance) of the REM 60cm telescope located at La Silla. 

The bright optical counterpart reported in GCN 13430 (Lacluyze et al.), GCN 13432 (Zheng et al.) and GCN 13438 (Elliot et al.) is well detected in the NIR at a peak magnitude of H = 11.90 + 0.05 between 2-4 minutes after the burst. The source was then fading rapidly remaining approximately at the same magnitude, H~13, for several more minutes.

Data have been calibrated by isolated not-saturated 2MASS stars in the field.