GCN Circular 1909
Subject
GRB 030226: R band polarimetric observations
Date
2003-02-28T15:42:42Z (21 years ago)
From
Stefano Covino at Brera Astronomical Observatory <covino@merate.mi.astro.it>
S. Covino, G. Ghisellini, D. Malesani, G. Tagliaferri, F. Zerbi (INAF Brera,
Italy); A. Cimatti, M. Della Valle, S. Di Serego (INAF Arcetri, Italy); F.
Fiore, G.L. Israel, L. Stella (INAF Roma, Italy); E. Costa, P. Soffitta (IASF
Roma, Italy), S. Mereghetti (IASF Milano, Italy), N. Kawai (Tokyo Tech,
Japan); D. Lazzati (IoA, Cambridge, UK); S. Ortolani (Univ. of Padova,
Italy); L. Pasquini (ESO, Germany); G. Ricker (MIT, USA); E. Le Floch, P.
Goldoni, F. Mirabel (CEA, France), E. Mason, P.M. Vreeswijk (ESO Paranal), P.
Price (RSAA, Australia), report:
We observed the optical counterpart to GRB 030226 (Suzuki et al. GCN1888; Fox
et al. GCN 1879) on February 27.261 (26.5 hours after the GRB trigger). The
observations were performed with the ESO VLT-UT1 (Antu) telescope equipped
with FORS1 and a Bessel R filter in the imaging polarimetry mode.
The transient source is clearly detected in the acquisition frames with
magnitudes:
R = 20.64 +/- 0.02 at 27.212 UT and
R = 20.79 +/- 0.02 at 27.261 UT.
Magnitude are calibrated following Garnavich et al. (GCN 1885).
Preliminary results for the analysis of the polarimetric frames in the R band
yielded a very strict upper limit:
P < 1.1% (95% confidence level) at 27.261 UT
The observation was performed about 14 hours after the break identified in the
afterglow lightcurve (Greiner et al. GCN 1894, Zeh et al. GCN 1898).
See also http://www.sissa.it/~malesani/GRB/030226 .
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