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arXiv · 0704.0864

Redshifts of the Long Gamma-Ray Bursts

Z. Bagoly·I. Csabai·A. Meszaros·P. Meszaros·I. Horvath·L. G. Balazs·R. Vavrek
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Abstract

The low energy spectra of some gamma-ray bursts' show excess components beside the power-law dependence. The consequences of such a feature allows to estimate the gamma photometric redshift of the long gamma-ray bursts in the BATSE Catalog. There is good correlation between the measured optical and the estimated gamma photometric redshifts. The estimated redshift values for the long bright gamma-ray bursts are up to z=4, while for the the faint long bursts - which should be up to z=20 - the redshifts cannot be determined unambiguously with this method. The redshift distribution of all the gamma-ray bursts with known optical redshift agrees quite well with the BATSE based gamma photometric redshift distribution.

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Z. Bagoly, I. Csabai, A. Meszaros, P. Meszaros, I. Horvath, L. G. Balazs, R. Vavrek. 2007-04-06. Redshifts of the Long Gamma-Ray Bursts. https://arxiv.org/abs/0704.0864

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