The GRB 030329 host: a blue low metallicity subluminous galaxy with intense star formation

/ Authors

J. Gorosabel, D. P'erez-Ram'irez, J. Sollerman, A. U. Postigo, J. Fynbo, A. Castro-Tirado, P. Jakobsson, P. Jakobsson, L. Christensen, J. Hjorth

and 8 more authors

G. J'ohannesson, S. Guziy, J. M. C. Cer'on, G. Björnsson, V. Sokolov, T. Fatkhullin, K. Nilsson, K. Nilsson

/ Abstract

We present broad band photometry and spectroscopic observations of the host galaxy of GRB 030329. Analysis of the spectral emission lines shows that the host is likely a low metallicity galaxy (Z ∼ 0.004). The spectral energy distribution (SED) constructed with the photometric points has been fitted using synthetic and observational templates. The best SED fit is obtained with a starburst template with an age of ∼150 Myr and an extinction Av ∼ 0.6. We find that the GRB 030329 host galaxy is a subluminous galaxy (L ∼ 0.016 L � ) with a stellar mass of 10 8 M� . Three independent diagnostics, based on the restframe UV continuum, the [O ii], and the Balmer emission lines, provide a consistent )

Journal: Astronomy and Astrophysics

DOI: 10.1051/0004-6361:20052768