Fulltext

Probing the Interstellar Medium and Stellar Environments of Long-Duration GRBs

Dessauges-Zavadsky, Miroslava ; Prochaska, Jason X. ; Chen, Hsiao-Wen

In: Proceedings of the International Astronomical Union, 2007, vol. 3, no. S250, p. 457-462

Add to personal list
    Title
    • Probing the Interstellar Medium and Stellar Environments of Long-Duration GRBs
    Author
    • Dessauges-Zavadsky, Miroslava. Geneva Observatory, University of Geneva, 51, Ch. des Maillettes, CH-1290 Sauverny, Switzerland email: miroslava.dessauges@obs.unige.ch
    • Prochaska, Jason X.. UCO/Lick Observatory, University of California, Santa Cruz, CA 95064, USA email: xavier@ucolick.edu
    • Chen, Hsiao-Wen. Department of Astronomy, University of Chicago, 5640 S. Ellis Ave., Chicago, IL 60637, USA email: hchen@oddjob.uchicago.edu
    Document Type
    • Postprint
    Language
    • English
    Published in
    • Proceedings of the International Astronomical Union, 2007, vol. 3, no. S250, p. 457-462. Cambridge University Press
    Other Version
    OAI-PMH Identifier
    • oai:doc.rero.ch:292429
    Summary
    We review the properties of the gas surrounding high-redshift gamma-ray bursts (GRBs) assessed through the analysis of damped Lyman-alpha systems (DLAs) identified in their afterglow spectra. These GRB-DLAs are characterized by large H I column densities with a median of N(H I) = 1021.7 cm−2, no molecular gas signatures, metallicities ranging from 1/100 to nearly solar with a median exceeding 1/10 solar, and no anomalous abundance patterns. The detection of the atomic Mg lines and the time-variability of the fine-structure lines demonstrates that the majority of the neutral gas along the GRB sightlines is located between 50 pc and a few kpc from the GRB. This implies that this gas is presumably associated with the ambient interstellar medium of the host galaxy and that the derived properties from low-ionization lines do not directly constrain the local environment of the GRB progenitor. The highly ionized gas, traced by N V lines, which could result from a pre-existing H II region produced by the GRB progenitor and neighboring OB stars, appears on the other hand to be very local to the GRB at about 10 pc, yielding a snapshot of the medium's physical conditions at this radius