• DOI:10.1142/S0218271813300280
• Corpus ID: 118678787

MEASURING COSMOLOGICAL PARAMETERS WITH GAMMA RAY BURSTS

@article{Amati2013MEASURINGCP,
  title={MEASURING COSMOLOGICAL PARAMETERS WITH GAMMA RAY BURSTS},
  author={Lorenzo Amati and Massimo Della Valle},
  journal={Eas Publications Series},
  year={2013},
  volume={36},
  pages={25-29}
}

• L. Amati, M. Valle
• Published 11 October 2013
• Physics
• Eas Publications Series

Gamma–Ray Bursts (GRBs) are potentially a very powerful tool for the measure of cosmological parameters. Indeed, they are the brightest sources in the universe (up to more than 1054 erg/s released in a few tens of s), their redshift distribution extends from about 0.1 to at least 6.7, and they radiate mostly in the hard X–ray band, thus avoiding, e.g. , the dust extinction problems affecting type Ia SNe. However, the luminosities of GRBs span several orders of magnitude, thus a way to “standardize” them in a way similar, e.g. , to what is done with type Ia SNe has to be found. Under this respect, the most promising and discussed tool is the correlation between the photon energy, E p,i , at which the ν Fν  spectrum peaks and the GRB radiated energy (E iso ) or luminosity (L iso , L p,iso ). By studying the scatter of these spectrum–energy correlations as a function of the adopted cosmology it is possible, with the present sample of ~80 GRBs with known redshift and spectral parameters, to derive, for a flat universe, significant constraints on Ω M consistent with the “concordance” cosmology value. Moreover, simulations show that, with the enlargement of the sample expected by present and future missions (Swift , GLAST/GBM, Konus–WIND, SVOM) it will be possible to simultaneously constrain both Ω M and Ω Λ , and, possibly, obtain information on the equation of state of dark energy and its evolution.