Very Different X-Ray-to-Optical Column Density Ratios in γ-Ray Burst Afterglows: Ionization in GRB Environments
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چکیده
منابع مشابه
Very Different X-ray to Optical Column Density Ratios in Γ-ray Burst Afterglows: Ionisation in Grb Environments
We compare the H I column densities from Lyα absorption to the metal column densities from X-ray absorption in γ-ray burst (GRB) afterglows. Eight bursts of seventeen entering the sample, have significant extragalactic X-ray absorptions. Of these we find a range in metallicities from sub-solar to a few hundred times the solar value. There is a complete lack of correlation between the X-ray and ...
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ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 2007
ISSN: 0004-637X,1538-4357
DOI: 10.1086/518310