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Probing cosmological parameters with GRBs

T. Di Girolamo·M. Vietri·G. Di Sciascio
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Abstract

In light of the recent finding of the narrow clustering of the geometrically-corrected gamma-ray energies emitted by Gamma Ray Bursts (GRBs), we investigate the possibility to use these sources as standard candles to probe cosmological parameters such as the matter density Omega_m and the cosmological constant energy density Omega_Lambda. By simulating different samples of gamma-ray bursts, based on recent observational results, we find that Omega_m (with the prior Omega_m + Omega_Lambda = 1) can be determined with accuracy ~7% with data from 300 GRBs, provided a local calibration of the standard candles be achieved.

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T. Di Girolamo, M. Vietri, G. Di Sciascio. 2004-01-13. Probing cosmological parameters with GRBs. https://doi.org/10.1063/1.1810900

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