1366 LGRB redshifts estimates with BARSE

This result is based on a careful selection and modeling of the population distribution of 1366 BATSE LGRBs in the five-dimensional space of redshift and the four intrinsic prompt gamma-ray emission properties: the isotropic 1024ms peak luminosity (L_iso_), the total isotropic emission (E_iso_), the spectral peak energy (E_pz_), as well as the intrinsic duration (T_90z_), while carefully taking into account the effects of sample incompleteness and the LGRB-detection mechanism of BATSE.

Two fundamental plausible assumptions underlie our purely probabilistic approach: (1) LGRBs trace, either exactly or closely, the cosmic star formation rate, with a possibility of the excess rates of LGRBs in the nearby universe, and (2) the joint four-dimensional distribution of the aforementioned prompt gamma-ray emission properties is well described by a multivariate log-normal distribution. Our modeling approach enables us to constrain the redshifts of individual BATSE LGRBs to within 0.36 and 0.96 average uncertainty ranges at 50% and 90% confidence levels, respectively.