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Spectroscopical Study of the Host Galaxy of GRB031203

R. Margutti·G. Chincarini·D. Fugazza
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Abstract

We revisit the host galaxy of GRB031203 using a set of spectra obtained with VLT. Assuming a Galactic color excess E(B-V)=0.72 (mag)in the direction of the burst,we derive an internal extinction of about 0.4 (mag). After correcting for reddening, we find an electronic density of 156 cm^{-3} and a temperature of 12443(K). With an ISM dominated by photo-ionization, we estimate a metallicity of 12+Log[O/H]=8.12 and a star formation rate of 12.3 (M_{o}yr^{-1}). This galaxy does not host a clearly detectable population of WR stars.

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R. Margutti, G. Chincarini, D. Fugazza. 2007-02-08. Spectroscopical Study of the Host Galaxy of GRB031203. https://arxiv.org/abs/astro-ph/0702225

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