13-18 December 2015
International Conference Centre Geneva
Europe/Zurich timezone

Measuring cosmological parameters with GRBs: status and perspectives

14 Dec 2015, 14:53
26m
Level 2, Room 14 (International Conference Centre Geneva)

Level 2, Room 14

International Conference Centre Geneva

17 Rue de Varembé, 1211 Geneva

Speaker

Lorenzo Amati (INAF - IASF Bologna)

Description

Given their huge isotropic-equivalent radiated energies, up to more than 10$^{54}$ erg released in a few tens of seconds, and their redshift distribution extending up to more than z = 9, Gamma-Ray Bursts (GRB) are in principle a powerful tool for measuring the geometry and expansion rate of the Universe. In the recent years, several attempts have been made to exploit the correlation between the photon energy at which the $\nu$F$\nu$ spectrum peaks ("peak energy") and the radiated energy (or luminosity) for "standardizing" GRBs and use them as tools (complementary to other probes like SN Ia, BAO and the CMB) for the estimate of cosmological parameters. These studies show that already with the present data set GRBs can provide a significant and independent confirmation of $\Omega_M$ $\sim$ 0.3 for a flat $\Lambda$CDM universe and that the measurements expected from present and next GRB experiments (e.g. Swift, Fermi/GBM, SVOM, CALET/GBM, UFFO) will allow us to substantially improve the constraints on $\Omega_M$ and $\Omega_\Lambda$, and, in particular, to get unique clues on dark energy properties and evolution.

Primary author

Lorenzo Amati (INAF - IASF Bologna)

Presentation Materials