[vsnet-grb-info 5942] GRB 080411: GROND detection of optical afterglow candidate

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  7586
SUBJECT: GRB 080411: GROND detection of optical afterglow candidate
DATE:    08/04/11 23:51:51 GMT
FROM:    Thomas Kruehler at MPE/MPI  <kruehler at mpe.mpg.de>

T. Kruehler, A. Kupcu Yoldas, J.Greiner, C. Clemens, A. Yoldas (all MPE
Garching) and G. Szokoly (Eoetvoes Univ., Budapest and MPE Garching)
report on behalf of the GROND team:

We observed the field of GRB 080411 detected by BAT (Marshall et al., GCN
#7584) simultaneously in g'r'i'z'JHK with GROND mounted at the 2.2m
ESO/MPI telescope at La Silla Observatory (Chile).

Observations started in twilight at 23:15 UT on April 11th, 2008, 2h after
the burst.

We detect a new bright point source just at the edge of the XRT error
circle (Marshall et al. GCN #7584) at

RA (J2000.0) = 02:31:55.20
DEC (J2000.0) = -71:18:07.6

with an uncertainty of 0.8".

The object is detected in all of the seven bands, implying a redshift
smaller than 3.5.

Preliminary photometry yields an r' band magnitudes of 16.5 calibrated
against USNO field stars.

The given magnitudes are not corrected for the Galactic foreground
reddening of E(B-V)=0.03 mag (Schlegel et al., 1998).