[vsnet-grb-info 3245] GRB060425: new MASTER survey method

[GCN Circulars]

TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  5080
SUBJECT: GRB060425: new MASTER survey method
DATE:    06/05/06 14:15:34 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <gcncirc at observ.inetcomm.ru>

V. Lipunov, V.Kornilov, N.Tyurina, A.Belinski, D.Kuvshinov, E.Gorbovskoy,
A.Krylov, N.Shatskiy, G.Borisov, A.Sankovich,  V.Vladimirov, P.Gritsyk, 
S.Korobkin

Sternberg Astronomical Institute, Moscow Union 'Optic'

In this circular we proposed and tested new method of optical observations 
of GRBs by wide field robotic telescopes: survey search of the optical 
transient like supurnovae in large error box GRBs or dark not X-ray GRB.
Especially this method is very important for bright short GRB, that 
frequently detected by all sky gamma-ray detectors (Konus-Wind, 
Ulysses, Odyssey, etc) and for which connection with supernovae is not 
clear.

The difference between "OT" and "SN" is the following: OT - is the new 
optical object without known galaxy. The SN pipe line reduction is based 
on the searching of the uncatalogized candidate near known galaxies (for 
example from HyperLeda, http://www-obs.univ-lyon1.fr/hypercat/).

MASTER  robotic system (http://observ.pereplet.ru, 6 square degrees field) 
observed GRB060425 error box (GRB_TIME is 2006-04-25 16:57:40 UT, IPN 
triangulation  GCN5005) in survey mode at considerable zenit distances. 
The weather was good.
We have 4 nights (1-2 hours per night) observations:

    Date    Days after GRB         Note                     Limit
 		mean 
2006-04-26     1.1           (Lipunov et al.GCN5008)        17.5
2006-04-27     2.1           (Lipunov et al.GCN5026)        17.5
2006-04-30     5.2                                          17.8
2006-05-03     8.1                                          17.6

The location of  our samples you can find at
http://observ.pereplet.ru/images/GRB060425/GRB060425_ErrorBox_master.jpg

The unfiltered image is calibrated relative to USNO A2.0 (0.8 R + 0.2 B).

The robot not find OT brighter then 17.0 in
large IPN error box (J. Cummings, S. Barthelmy et al. GCN5005).

The robot not find SN brighter then 17.5.
Father observations of the GRB050425 not planed.

MASTER team  thanks to Konus-Wind team for collaboration. This work is 
supported by RFFI  04-02-16411 grant.
This message can be cited.
Mailto: lipunov at sai.msu.ru