TESTING THE POSSIBLE INTRINSIC ORIGIN OF THE EXCESS VERY STRONG Mg ii ABSORBERS ALONG GAMMA-RAY BURST LINES-OF-SIGHT

@article{Cucchiara2008TESTINGTP,
  title={TESTING THE POSSIBLE INTRINSIC ORIGIN OF THE EXCESS VERY STRONG Mg ii ABSORBERS ALONG GAMMA-RAY BURST LINES-OF-SIGHT},
  author={A. Cucchiara and Therese M. Jones and Jane C. Charlton and Derek B. Fox and Derek Einsig and A. Narayanan},
  journal={The Astrophysical Journal},
  year={2008},
  volume={697},
  pages={345 - 360}
}
The startling discovery by Prochter et al. that the frequency of very strong (Wr(2796)>1 Å) Mg ii absorbers along gamma-ray burst (GRB) lines of sight ([dN/dz]GRB = 0.90) is more than three times the frequency along quasar lines of sight ([dN/dz]QSO = 0.24), over similar redshift ranges, has yet to be understood. In particular, explanations appealing to dust antibias in quasar samples, partial covering of the quasar sources, and gravitational-lensing amplification of the GRBs have all been… 
AN INDEPENDENT MEASUREMENT OF THE INCIDENCE OF Mg ii ABSORBERS ALONG GAMMA-RAY BURST SIGHT LINES: THE END OF THE MYSTERY?
In 2006, Prochter et al. reported a statistically significant enhancement of very strong Mg ii absorption systems intervening the sight lines to gamma-ray bursts (GRBs) relative to the incidence of
On the Significance of the Excess Number of Strong Mg II Absorbers Observed toward Gamma-Ray Bursts
The number of strong (equivalent width >1 Å) 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
Statistics and characteristics of MgII absorbers along GRB lines of sight observed with VLT-UVES
We analyze the properties of Mg ii absorption systems detected along the sightlines toward GRBs using a sample of 10 GRB afterglow spectra obtained with VLT-UVES over the past six years. The
CASTING LIGHT ON THE ANOMALOUS STATISTICS OF Mg II ABSORBERS TOWARD GAMMA-RAY BURST AFTERGLOWS: THE INCIDENCE OF WEAK SYSTEMS
We revisit echelle spectra (spectral resolution R ≈ 40,000) of eight gamma-ray burst (GRB) afterglows to obtain the incidence (dN/dz) of weak intervening Mg ii systems at a mean redshift of 〈z〉 =
TESTING GRAVITATIONAL LENSING AS THE SOURCE OF ENHANCED STRONG Mg ii ABSORPTION TOWARD GAMMA-RAY BURSTS
Sixty percent of gamma-ray bursts (GRBs) reveal strong Mg ii absorbing systems, which is a factor of ∼2 times the rate seen along lines of sight to quasars. Previous studies argue that the
Constraints on the relative sizes of intervening Mg II-absorbing clouds and quasar emitting regions
Context. A significantly higher incidence of strong (rest equivalent width Wr > 1A) intervening Mgiiabsorption is observed along gamma-ray burst (GRB) sight-lines relative to those of quasar
Clustering of galaxies around gamma-ray burst sight-lines
There is evidence of an overdensity of strong intervening MgII absorption line systems distributed along the lines of sight toward gamma-ray burst (GRB) afterglows relative to quasar sight-lines. If
GRBs as Probes of the IGM
Gamma-ray Bursts (GRBs) are the most powerful explosions known, capable of outshining the rest of gamma-ray sky during their short-lived prompt emission. Their cosmological nature makes them the best
On the incidence of Mg II absorbers along the blazar sightlines
It is widely believed that the cool gas clouds traced by MgII absorption, within a velocity offset of 5000 km/s relative to the background quasar are mostly associated with the quasar itself, whereas
DUSTY Mg ii ABSORBERS: IMPLICATIONS FOR THE GAMMA-RAY BURST/QUASAR INCIDENCE DISCREPANCY
There is nearly a factor of 4 difference in the number density of intervening Mg ii absorbers as determined from gamma-ray burst (GRB) and quasar lines of sight. We use a Monte Carlo simulation to
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