Testing the consistency of new Amati-correlated gamma-ray burst dataset cosmological constraints with those from better-established cosmological data

TL;DR

This study assesses whether a new gamma-ray burst dataset can reliably constrain cosmological parameters and finds significant tension with established data, questioning its utility for cosmology.

Contribution

It introduces a combined analysis of 151 GRBs with the Amati correlation across multiple cosmological models, highlighting limitations and inconsistencies with standard probes.

Findings

A123 and A28 datasets are standardizable via Amati correlation.

Constraints from these datasets show >2σ tension with $H(z)$+BAO data.

Limited sample size and high scatter reduce the statistical power of the A28 dataset.

Abstract

Gamma-ray bursts (GRBs) are promising cosmological probes for exploring the Universe at intermediate redshifts ($z$). We analyze 151 Fermi-observed long GRBs (datasets A123 and A28) to simultaneously constrain the Amati correlation and cosmological parameters within six spatially flat and nonflat dark energy models. We find that these datasets are standardizable via a single Amati correlation, suggesting their potential for cosmological analyses. However, constraints on the current value of the nonrelativistic matter density parameter from A123 and the combined A123 + A28 data exhibit $>2\sigma$ tension with those derived from a joint analysis of better-established Hubble parameter [$H(z)$] and baryon acoustic oscillation (BAO) data for most considered cosmological models. This tension indicates that these GRB data are unsuitable for jointly constraining cosmological parameters with better-established $H(z)$ + BAO and similar data. Although the A28 data constraints are consistent with the $H(z)$ + BAO data constraints, its limited sample size (28 GRBs) and high intrinsic scatter ($\sim0.7$) diminishes its statistical power compared to existing datasets.