Dust Extinction Bias in the Column Density Distribution of Gamma-Ray Bursts: High Column Density, Low-redshift GRBs are More Heavily Obscured

@article{Watson2012DustEB,
  title={Dust Extinction Bias in the Column Density Distribution of Gamma-Ray Bursts: High Column Density, Low-redshift GRBs are More Heavily Obscured},
  author={Darach Watson and Palle Moller Dark Cosmology Centre and University of Iceland},
  journal={The Astrophysical Journal},
  year={2012},
  volume={754},
  pages={89}
}
The afterglows of gamma-ray bursts (GRBs) have more soft-X-ray absorption than expected from the foreground gas column in the Galaxy. While the redshift of the absorption can in general not be constrained from current X-ray observations, it has been assumed that the absorption is due to metals in the host galaxy of the GRB. The large sample of X-ray afterglows and redshifts now available allows the construction of statistically meaningful distributions of the metal column densities. We… Expand

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