IAFE   05512
INSTITUTO DE ASTRONOMIA Y FISICA DEL ESPACIO
Unidad Ejecutora - UE
artículos
Título:
Probing the complex environments of GRB host galaxies and intervening systems: high resolution spectroscopy of GRB050922C
Autor/es:
PIRANOMONTE, S.; WARD, P. A.; FIORE, F.; VERGANI, S. D.; D'ELIA, V.; KRONGOLD, Y.; NICASTRO, F.; MEURS, E. J. A.; CHINCARINI, G.; COVINO, S.; DELLA VALLE, M.; FUGAZZA, D.; NORCI, L.; SBORDONE, L.; STELLA, L.; TAGLIAFERRI, G.; BURROWS, D. N.; GEHRELS, N.; GOLDONI, P.; MALESANI, D.; MIRABEL, I. F.; PELLIZZA, L. J.; PERNA, R.
Revista:
ASTRONOMY AND ASTROPHYSICS
Editorial:
EDP Sciences
Referencias:
Lugar: Les Ulis, Francia; Año: 2008 vol. 492 p. 775 - 785
ISSN:
0004-6361
Resumen:
Aims. The aim of this paper is to investigate the environment of gamma
ray bursts (GRBs) and the interstellar matter of their host galaxies.
Methods: To this purpose we use high resolution spectroscopic
observations of the afterglow of GRB050922C, obtained with UVES/VLT ~
3.5 h after the GRB event. Results: We found that, as for most high
resolution spectra of GRBs, the spectrum of the afterglow of GRB050922C
is complex. At least seven components contribute to the main absorption
system at z=2.1992. The detection of lines of neutral elements like MgI
and the detection of fine-structure levels of the ions FeII, SiII and
CII allows us to separate components in the GRB ISM along the line of
sight. Moreover, in addition to the main system, we analyzed the five
intervening systems between z = 2.077 and z = 1.5664 identified along
the GRB line of sight. Conclusions: GRB afterglow spectra are very
complex, but full of information. This can be used to disentangle the
contribution of the different parts of the GRB host galaxy and to study
their properties. Our metallicity estimates agree with the scenario of
GRBs exploding in low metallicity galaxies.