On the Significance of the Excess Number of Strong Mg II Absorbers Observed toward Gamma-Ray Bursts

@article{Rapoport2013OnTS,
  title={On the Significance of the Excess Number of Strong Mg II Absorbers Observed toward Gamma-Ray Bursts},
  author={Sharon Rapoport and Christopher A. Onken and J. S. B. Wyithe and B P Schmidt and Anders O. Thygesen},
  journal={The Astrophysical Journal},
  year={2013},
  volume={766},
  pages={23}
}
The number of strong (equivalent width >1 A) Mg II absorbers observed toward gamma-ray bursts (GRBs) has been found to be statistically larger than the number of strong absorbers toward quasi-stellar objects (QSOs). We formalize this "Mg II problem" and present a detailed explanation of the statistical tools required to assess the significance of the discrepancy. We find that the problem exists at the 4σ level for GRBs with high-resolution spectra. It has been suggested that the discrepancy can… 

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