2005/08/31 by R. L. C. Starling, P. M. Vreeswijk, S. L. Ellison +13 · 2 citations
Physics and Astronomy · #Absorption (acoustics) #Absorption spectroscopy #Afterglow #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Galaxy #Gamma-ray burst #Gamma-ray bursts and supernovae #Metallicity #Optics #Physics #Redshift #Spectral line #Spectroscopy #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1051/0004-6361:200500181
5 pages, 2 figures. Accepted for A&A Letters
arxiv created 2005/09/12 · openalex publication_date 2005/10/07 · arxiv updated 2009/12/01 · openalex created_date 2021/02/01 · openalex updated_date 2026/08/05
We present early WHT ISIS optical spectroscopy of the afterglow of gamma-ray burst GRB 050730. The spectrum shows a DLA system with the highest measured hydrogen column to date: N(H ) = at the third-highest GRB redshift z = 3.968. Our analysis of the Swift XRT X-ray observations of the early afterglow show X-ray flares accompanied by decreasing X-ray absorption. From both the optical and the X-ray spectra we constrain the dust and gas properties of the host galaxy. We find the host to be a low metallicity galaxy, with low dust content. Much of the X-ray absorbing gas is situated close to the GRB, whilst the H I absorption causing the DLA is most likely located further out.