Gamma-Ray Bursts: Characteristics and Prospects

Frontiers in Theoretical and Applied Physics/UAE 2017

Azzam, W.J.^1 ; Zitouni, H.^2 ; Guessoum, N.^3

Department of Physics, College of Science, University of Bahrain, Sakhir, Bahrain^1

PTEAM Laboratory, Faculty of Science, University Dr. Yahia Fares, Algeria^2

Department of Physics, American University of Sharjah, United Arab Emirates^3

关键词: Afterglow characteristics;    Cosmological probes;    External shocks;    Gamma ray bursts;    Gamma-ray bursts (GRBs);    Isotropic energy;    Spectral peak energies;    Star formation rates;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/869/1/012065/pdf
DOI  :  10.1088/1742-6596/869/1/012065

来源: IOP

【 摘 要 】

Gamma-ray bursts (GRBs) are the most powerful explosions in the universe. They have remained the object of intense research ever since their discovery was declassified in the early 1970s. Several space-borne missions have been dedicated to their study, including the Compton Gamma-Ray Burst Observatory (CGRO) in the 1990s and the current Swift and Fermi satellites. However, despite several decades of focused research, the precise mechanisms behind these enigmatic explosions have not been fully established. In the first part of this paper, we review what is currently known about GRBs. This includes: GRB light-curves and spectra; the different progenitor models, i.e., the "collapsar" and "merger" models; and the afterglow characteristics, including external shocks and the surrounding medium. In the second part of the paper, we present our work, which focuses on utilizing GRBs as cosmological probes. GRBs are ideal cosmological tools, because they have been observed to great distances (redshifts up to z = 9.4) and their radiation is unencumbered by any intervening dust. Although GRBs are not standard candles, the discovery of several energy and luminosity correlations, like the Amati relation which correlates the intrinsic spectral peak energy, Ep,ito the equivalent isotropic energy, Eiso, has ushered in a new era in which GRBs are used to investigate cosmological issues like the star formation rate and the value of the matter-density parameter, ΩM.