Cosmology-Independent Distance Moduli of 42 Gamma-Ray Bursts between Redshift of 1.44 and 6.60

TL;DR

This paper derives cosmology-independent distance moduli for 42 gamma-ray bursts using supernova data, enabling constraints on cosmological parameters without assuming a specific cosmological model.

Contribution

It introduces a method to obtain GRB distance moduli independent of cosmological assumptions by interpolating supernova data and calibrating GRB relations.

Findings

Distance moduli for 42 GRBs between redshift 1.44 and 6.60 are provided.

Uncertainties in the distance moduli are between 1% and 3%.

The method allows for cosmology-independent analysis of high-redshift GRBs.

Abstract

This report is an update and extension of our paper accepted for publication in ApJ (arXiv:0802.4262). Since objects at the same redshift should have the same luminosity distance and the distance moduli of type Ia supernovae (SNe Ia) obtained directly from observations are completely cosmology independent, we obtain the distance modulus of a gamma-ray burst (GRB) at a given redshift by interpolating or iterating from the Hubble diagram of SNe Ia. Then we calibrate five GRB relations without assuming a particular cosmological model, from different regression methods, and construct the GRB Hubble diagram to constrain cosmological parameters. Based upon these relations we list the cosmology-independent distance moduli of 42 GRBs between redshift of 1.44 and 6.60, with the 1-$\sigma$ uncertainties of 1-3%.