[AAVSO-HEN] GRB 090323: Faulkes Telescope South Observations

[grb at aavso.org]

The following is a GCN Circular circulated via the AAVSO network.
For an archive and more information on circulars visit:
http://lheawww.gsfc.nasa.gov/docs/gamcosray/legr/bacodine/gcn3_archive.html

TITLE:   GCN CIRCULAR
NUMBER:  9039
SUBJECT: GRB 090323: Faulkes Telescope South Observations
DATE:    09/03/26 10:11:36 GMT
FROM:    Cristiano Guidorzi at Ferrara U,Italy  <guidorzi at fe.infn.it>

C. Guidorzi (U. Ferrara), I. A. Steele, A. Melandri, D. Bersier 
(Liverpool JMU),
A. Gomboc (U. Ljubljana), S. Kobayashi, C.J. Mottram, C.G.  Mundell,
R.J. Smith (Liverpool JMU), P. O'Brien, N. Bannister, N. Tanvir (U. 
Leicester)
on behalf of a large collaboration report:

The 2-m Faulkes Telescope South (Siding Spring, Australia) began observing
the afterglow (Updike et al., GCN Circ. 9026; Cenko et al., GCN Circ. 9027)
of the Fermi GBM/LAT GRB 090323 (Ohno et al., GCN Circ. 9021; van der Horst
et al., GCN Circ. 9035) on March 25, 11:50:55 UT, i.e. at 2.49 days post 
burst.

Observations were carried out in filters R and i. The afterglow is
clearly detected in both filters with the following magnitudes:

Filter  Tmid(days)    Exposure(s)    Mag
-------------------------------------------------
   i       2.50         6x300        21.3 +/- 0.2
   R       2.53         6x300        21.7 +/- 0.1
-------------------------------------------------

Magnitudes are calibrated with respect to nearby SDSS stars.
Comparing with previous reports (Kann et al., GCN Circ. 9033; Wang et al.,
GCN Circ. 9034; Perley et al., GCN Circ. 9036; Burenin et al., GCN Circ. 
9037)
we confirm the steepening of the decay.