TITLE:   GCN CIRCULAR
NUMBER:  8761
SUBJECT: GRB 090102: TAROT Calern observatory optical observations
DATE:    09/01/02 03:08:29 GMT
FROM:    Alain Klotz at CESR-CNRS  <Alain.Klotz@free.fr>

Klotz, A. (CESR-OMP), Gendre, B. (LAM_OAMP),
  Boer M. (OHP), Atteia J.L. (LATT-OMP) report:

We imaged the field of GRB 090102 detected by SWIFT
(trigger 338895) with the TAROT robotic telescope (D=25cm)
located at the Calern observatory, France.

The observations started 40.8s after the GRB trigger
(6.8s after the notice). The elevation of the field decreased from
from 68 degrees above horizon and weather conditions
were good.

We detect a new fading source in the error box given by SWIFT
at the following position (+/- 1 arcsec):

RA(J2000.0) = 08h 32m 38.1s
DEC(J2000.0) +33d 11' 45.3"

OT was R~15.3 at about 100s after GRB.

Magnitudes were estimated with the nearby USNO-B1 stars
and are not corrected for galactic dust extinction.

N.B. Galactic coordinates are lon=189.8804 lat=+34.6651
and the galactic extinction in R band is 0.1 magnitudes
estimated from D. Schlegel et al. 1998ApJ...500..525S.

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