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arXiv · astro-ph/0312264

SN 2002lt and GRB 021211: a SN/GRB Connection at z = 1

M. Della Valle·D. Malesani·S. Benetti·V. Testa·M. Hamuy·L. A. Antonelli·G. Chincarini·G. Cocozza·S. Covino·P. D'Avanzo·D. Fugazza·G. Ghisellini·R. Gilmozzi·D. Lazzati·E. Mason·P. Mazzali·L. Stella
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Abstract

We present spectroscopic and photometric observations of the afterglow of GRB 021211 and the discovery of its associated supernova, SN 2002lt. The spectrum shows a broad feature (FWHM = 150 A), around 3770 A (in the rest-frame of the GRB), which we interpret as Ca H+K blueshifted by 14400 km/s. Potential sources of contamination due to the host galaxy and/or residuals of telluric absorption have been analyzed and ruled out. Overall, the spectrum shows a suggestive resemblance with the one of the prototypical type-Ic SN 1994I. This might indicate that GRBs are produced also by standard type-Ic supernovae.

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M. Della Valle, D. Malesani, S. Benetti, V. Testa, M. Hamuy, L. A. Antonelli, G. Chincarini, G. Cocozza, S. Covino, P. D'Avanzo, D. Fugazza, G. Ghisellini, R. Gilmozzi, D. Lazzati, E. Mason, P. Mazzali, L. Stella. 2003-12-10. SN 2002lt and GRB 021211: a SN/GRB Connection at z = 1. https://doi.org/10.1063/1.1810874

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