Probing cosmological parameters with GRBs
  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. 
T. Di Girolamo (1), M. Vietri (2) and G. Di Sciascio (1) ((1) INFN,   Sezione di Napoli, Italy (2) Scuola Normale Superiore,...