GCN Circular 2600

GRB040511: REM telescope robotic NIR observations.

V. Testa, L.A. Antonelli (INAF-OAR), L.Calzoletti (Univ. Roma Sapienza),
S. Covino (INAF-OAB), G. Chincarini (Univ. Milano Bicocca), F. M. Zerbi
(INAF-OAB), E. Palazzi (IASF-CNR,Bologna), G. Tosti (Univ. Perugia),
L. Nicastro (IASF-CNR,Palermo), on behalf of the REM collaboration report:

On May 12 the 60cm robotic telescope REM at ESO-La Silla observed the field of
GRB040511, that was detected by HETE2 ~12 hours before, during day time at
La Silla. The observations were performed with the REMIR near-IR camera during
commissioning phase in the wide band filters J,H and Ks in fully
automatic mode, following a predefined sequence suited for late grb alerts.
Frames obtained in the three filters were co-added together to obtain
three images per filter, having total exposure times of 60, 360 and 720s.
The comparison with the 2MASS catalog did not reveal evident new sources,
with 3 sigma upper limits, on the 720s images, of 18.6 in the J filter,
18.2 in the H filter and 16.6 in the Ks filter. Images were calibrated by 
using a number of 2MASS stars in the field with high S/N ratio. 
It was not possible to observe simultaneously in the optical bands because the 
optical spectrograph ROSS was in maintenance.

[GCN OPS NOTE:  This Circular was delayed 13 hours until daytime
when I could register V.Testa as a new member of the list.]