Abstract
Gamma‐ray bursts have been proved to be detectable up to distances much larger than any other astrophysical object, providing the most effective way, complementary to ordinary surveys, to study the high redshift universe. To this end, we present here the results of an observational campaign devoted to the study of the high‐z GRB 090205 that led to the detection of the optical afterglow and host galaxy and to the first measure of its redshift, z = 4.65. Photometric observations of the GRB 090205 host galaxy argue in favor of a starburst galaxy with a stellar population younger than ∼150 Myr. Moreover, the metallicity of Z>0.27 Z⊙ derived from the GRB afterglow spectrum is among the highest derived from GRB afterglow measurement at high‐z, suggesting that the burst occured in a rather enriched envirorment. Finally, a detailed analysis of the afterglow spectrum shows the existence of a line corresponding to Lyman‐α emission at the redshift of the burst. GRB 090205 is thus hosted in a typical Lyman‐α emitter (LAE) at z = 4.65. This makes the GRB 090205 host the farthest GRB host galaxy, spectroscopically confirmed, detected to date.
Submitted Version (
Free)
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call