Talk detail

Participant	Amati, Lorenzo
Institution	INAF - IASF Bologna - via P. Gobetti, 101 - Bologna - BO - Italy

Session	GRB4	Accepted	Yes	Order	2	Time	14:35 - 14:55
Talk	Oral abstract	Title	On the reliability of the Ep,i - intensity correlation in GRBs
Co-authors
Abstract	The reliability of the Ep,i - Eiso and other spectrum - intensity correlations is a hotly debated topic, given its relevance for both GRB physics and cosmology. I provide a critical review of the results of different studies based both on the analysis of large datasets of GRBs without measured redhsift and Monte Carlo simulations aimed at evaluating the impact of selection and instrumental effects on the distribution of GRBs in the Ep,i - Eiso plane. I will show that, by considering both theoretical and real detection and spectroscopic thresholds, together with different possible distributions of the redshift, spectral parameters and radiated energy,the observed Ep,i - Eiso relation cannot be reproduced by assuming the null hypothesis that the two quantites are completely uncorrelated. The physical nature of the Ep,i - intensity correlation is also confirmed by its existence within single GRBs.

Session	OC3	Accepted	Yes	Order	1	Time	14:00 - 14:20
Talk	Oral abstract	Title	Measuring cosmological parameters with GRBs: status & perspectives
Co-authors
Abstract	Given their huge isotropic-equivalent luminosities, up to more than 10^54 erg/s, and their redshift distribution extending up to more than z = 8, Gamma-Ray Bursts (GRB) are in principle a powerful tool for measuring the geometry and expansion rate of the Univeverse. However, they are not standard candles, given that their luminosities span several orders of magnitude, even when considering possible collimation angles. In the recent years, several attempts 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 using them as tools, complementary to other probes like SN Ia, BAO and the CMB, for the estimate of cosmological parameters have been made. These studies show that already with the present data GRBs can provide a significant and independent confirmation of Omega _M ~ 0.3 for a flat LambdaCDM universe and that the measurements expected from present and next GRB experiments (e.g. Swift , Fermi/GBM, SVOM) will allow us to constrain Omega _M, Omega Lambda and, in particular, to get clues on dark energy properties and evolution.

Session	SO5	Accepted	Yes	Order	4	Time	15:45 - 16:05
Talk	Oral abstract	Title	GAME: GRB and All-sky monitor Experiment
Co-authors	F. Frontera, C. Labanti, J. Braga, Y. Evangelista, F. Fuschino, R. Hudec, S. Kobayashi, T. Rodic, F. Ryde, A. Santangelo, R: Ruffini, G. Tagliaferri, A. Vacchi, P. Attinà, P. Rosati and the GAME collaboration
Abstract	We describe the “GRB and All-sky monitor Experiment (GAME)” mission submitted in response to the ESA Call for a Small mission opportunity for a launch in 2017. The general scientific objective is to perform measurements of key importance for GRB science and to provide the wide astrophysical community of an advanced X-ray all-sky monitoring system. The proposed payload is based on Silicon Drift Detectors (~1 – 50 keV), CdZnTe (hereafter CZT) detectors (15-200 keV) and crystal scintillators in phoswich (NaI/CsI) configuration (20 keV – 20 MeV), three well established technologies. In addition to ESA, the mission forsees main support by AEB (Brazil) and ASI (Italy), together with minor contributions from DLR (Germany), Czech Republic (MoT, CSA) and the Slovenian SPACE-Sl.