TITLE:   GCN CIRCULAR
NUMBER:  5718
SUBJECT: GRB 061006: optical afterglow
DATE:    06/10/08 12:09:35 GMT
FROM:    Daniele Malesani at SISSA-ISAS,Trieste,Italy  <malesani@sissa.it>

Daniele Malesani (SISSA/ISAS), Luigi Stella (INAF/OAR), Paolo D'Avanzo, 
Stefano Covino (INAF/OABr), Emmanuele Jehin, Chris Lidman, and Dominique 
Naef (ESO) report on behalf of the MISTICI collaboration

We observed again the field of the short GRB 061006 (Schady et al., GCN 
5699; Krimm et al., GCN 5704), with the ESO-VLT UT2 equipped with FORS1. 
Observations were carried out in the I band (30 minutes on source), and 
started on 2006 Oct 8.2936 UT (1.60 days after the GRB). The seeing 
(0.85") was comparable to that of our previous observation.

We still detect the two sources reported by Malesani et al. (GCN 5705). 
The object inside the XRT error circle (alpha = 07:24:07.66, delta = 
-79:11:55.1) has faded by 0.53 +- 0.09 mag with respect to our previous 
observation. We thus suggest that this source is the optical afterglow 
of GRB 061006, possibly contaminated by the host galaxy. In fact, the 
inferred power-law decay slope is quite shallow (alpha = 0.50+-0.08). 
However, the object in the last epoch is not clearly extended.

The lack of a bright galaxy suggests that this short burst is not very 
nearby.

Further observations are planned.