Measuring Cosmological Parameters with Gamma-Ray Bursts

Abstract

Gamma-Ray Bursts (GRB) emit in a few dozen of seconds up to ~10<SUP>54</SUP> erg, in terms of isotropic equivalent radiated energy E<SUB>iso</SUB>, therefore they can be observed up to z ~ 10 and appear very promising tools to describe the expansion rate history of the Universe. In this paper we review the use of the E<SUB>p,i</SUB>-E<SUB>iso</SUB> correlation of Gamma-Ray Bursts to measure Ω<SUB>M</SUB>. We show that the present data set of GRBs, coupled with the assumption that we live in a flat universe, can provide indipendent evidence, from other probes, that Ω<SUB>M</SUB>~0.3. We show that current (e.g., Swift, Fermi/GBM, Konus-WIND) and next GRB experiments (e.g., CALET/GBM, SVOM, Lomonosov/UFFO, LOFT/WFM) will allow us, within a few years, to constrain Ω<SUB>M</SUB> and the evolution of dark energy with time, with an accuracy comparable to that currently exhibited by SNe-Ia.