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arXiv · 1206.5558

The mystery of the missing GRB redshifts

David Coward·Eric Howell·Marica Branchesi·Dafne Guetta·Chadia Kanaan
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Abstract

It is clear that optical selection effects have distorted the "true" GRB redshift distribution to its presently observed biased distribution. We constrain a statistically optimal model that implies GRB host galaxy dust extinction could account for up to 40% of missing optical afterglows and redshifts in $z = 0-3$, but the bias is negligible at very high-$z$. The limiting sensitivity of the telescopes, and the time to acquire spectroscopic/photometric redshifts, are significant sources of bias for the very high-$z$ sample. We caution on constraining star formation rate and luminosity evolution using the GRB redshift distribution without accounting for these selection effects.

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David Coward, Eric Howell, Marica Branchesi, Dafne Guetta, Chadia Kanaan. 2012-06-25. The mystery of the missing GRB redshifts. https://arxiv.org/abs/1206.5558

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