T. Kruehler, J. Greiner, S. McBreen, S. Loew, A. Kuepcue-Yoldas, A. Yoldas
(all MPE Garching) report for the GROND team:
We started observing GRB 080120 observed by INTEGRAL (Mereghetti et al. 2008,
GCN #7194) simultaneously in grizJHK with GROND, mounted at the 2.2m MPI/ESO
telescope at La Silla (Chile), at 7:02 UT, about 13.5 hrs after the GRB.
At this time, the GRB location was becoming visible at 20 degrees
We find an optical/NIR source inside the 3.8 arcsec Swift/XRT error circle
of the X-ray afterglow (Sbarufatti et al. 2008, GCN #7195). The object is
seen in all bands except K, implying a redshift smaller than 3.5.
The coordinates are (+-1 arcsec):
RA (2000.0) = 15h 01m 03.2s
Decl (2000.0) = -10d 52' 30"
We estimate rough magnitudes of g'=21.1, r'=20.5, i'=20.0, z'=19.8,
J=19.6, H=19.4, K>18.9, calibrated against USNO and 2MASS stars.
Given the high airmass and humidity, these estimates may have large errors.
No statement about variability can be made at this point. Observations are