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Polarization Evolution of the GRB 020405 Afterglow

S. Covino·D. Malesani·G. Ghisellini·D. Lazzati·S. di Serego Alighieri·M. Stefanon·A. Cimatti·M. Della Valle·F. Fiore·P. Goldoni·N. Kawai·G. L. Israel·E. Le Floc'h·I. F. Mirabel·G. Ricker·P. Saracco·L. Stella·G. Tagliaferri·F. M. Zerbi
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Abstract

Polarization measurements for the optical counterpart to GRB 020405 are presented and discussed. Our observations were performed with the VLT-UT3 (Melipal) during the second and third night after the gamma-ray burst discovery. The polarization degree (and the position angle) appears to be constant between our two observations at a level around (1.5 - 2)%. The polarization can be intrinsic but it is not possible to unambiguously exclude that a substantial fraction of it is induced by dust in the host galaxy.

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S. Covino, D. Malesani, G. Ghisellini, D. Lazzati, S. di Serego Alighieri, M. Stefanon, A. Cimatti, M. Della Valle, F. Fiore, P. Goldoni, N. Kawai, G. L. Israel, E. Le Floc'h, I. F. Mirabel, G. Ricker, P. Saracco, L. Stella, G. Tagliaferri, F. M. Zerbi. 2002-11-12. Polarization Evolution of the GRB 020405 Afterglow. https://doi.org/10.1051/0004-6361%3A20030133

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