{
  "bibcode": "2002GCN..1431....1C",
  "body": "S. Covino, G. Ghisellini, D. Malesani, P. Saracco, G. Tagliaferri, F.  Zerbi\n(Observ. of Brera, Milan, Italy); S. Di Serego, A. Cimatti, M. Della Valle\n(Observ. of Arcetri, Florence, Italy); F. Fiore, G.L. Israel, L. Stella\n(Observ. of Monte Porzio, Rome, Italy); M. Vietri (Univ. Rome 3, I); N.  Kawai\n(Tokyo Tech, Japan); D. Lazzati (IoA, Cambridge, UK); S. Ortolani (Univ.  of\nPadua, Italy); L. Pasquini (ESO, Germany); G. Ricker (MIT, USA); E. Le Floch,\nP. Goldoni, F. Mirabel (CEA, F)  report:\n\n\nOn 2002 April 7.21 and April 8.26 we observed the optical counterpart to\nGRB020405. The observations were performed with the ESO VLT-3 (Melipal)\ntelescope equipped with FORS1 with a Bessel V band filter in the imaging\npolarimetry mode. The transient source is clearly detected superposed to a\nbright galaxy. The acquisition images allowed us to derive the magnitude of\nthe transient as reported in GCN 1337 and GCN 1345 (Covino et al.).\n\nOn April 7.21 (2.1 days after the GRB) we found linear polarization at the\nlevel of 1.93 +/- 0.33 per cent with position angle 154 +/- 5 degrees while\non April 8.26 (3.2 days after the GRB) we found linear polarization at the\nlevel of 1.23 +/- 0.43 per cent with position angle 168 +/- 9 degrees.\nPolarization measurements were corrected for any instrumental effect or\nmeasurement bias and the reported polarization degrees and position angles\nare derived from Stokes parameters normalized to the average of the field\nstars.\n\n\nThis message is citeable.",
  "circularId": 1431,
  "createdOn": 1024481748000,
  "email": "covino@merate.mi.astro.it",
  "subject": "GRB020405: polarimetric observations",
  "submitter": "Stefano Covino at Brera Astronomical Observatory  <covino@merate.mi.astro.it>",
  "eventId": "GRB 020405"
}