Gamma-ray bursts from stellar remnants: probing the Universe at high redshift

Abstract

A gamma‐ray burst (GRB) releases an amount of energy similar to that of a supernova explosion, which combined with its rapid variability suggests an origin related to neutron stars or black holes. Since these compact stellar remnants form from the most massive stars not long after their birth, GRBs should trace the star formation rate in the Universe; we show that the GRB flux distribution is consistent with this. Because of the strong evolution of the star formation rate with redshift, it follows that the dimmest known bursts have z ∼ 6, much above the value usually quoted and beyond the most distant quasars. This explains the absence of bright galaxies in well‐studied GRB error boxes. The increased distances imply a peak luminosity of 8.3 × 1051 erg s−1 and a rate density of 0.025 per million years per galaxy. These values are 20 times higher and 150 times lower, respectively, than are implied by fits with non‐evolving GRB rates. This means either that GRBs are caused by a much rarer phenomenon than mergers of binary neutron stars, or that their gamma‐ray emission is often invisible to us due to beaming. Precise burst locations from optical transients will discriminate between the various models for GRBs from stellar deaths, because the distance between progenitor birth place and burst varies greatly among them. The dimmest GRBs are then the most distant known objects, and may probe the Universe at an age when the first stars were forming.

GRB 010222: A Burst within a Starburst

“…Multiwavelength studies of GRBs and their host galaxies have the potential both to determine the fraction of star formation that is optically obscured (Wijers et al 1998 ;Totani 1999 ;Blain & Natarajan 2000) and to elucidate the relation between the optical/UV and submillimeter-selected galaxies. To the degree that GRBs trace massive star formation in the early universe (Bloom et al 1999 ;Galama et al 2000 ;Piro et al 2000 ;Bloom, Kulkarni, & Djorgovski 2000 ;Reichart 2001), then the extreme luminosity and the dust-penetrating ability of c-rays can be used to select highredshift galaxies in an unbiased way without regard to their emission properties.…”

Measuring dark energy with theEiso–Epcorrelation of gamma-ray bursts using model-independent methods

“…Therefore, they are promising probes for the highredshift Universe (for a recent review, see Wang et al 2015). Many studies have been carried out to use GRBs for cosmological purposes, such as the star formation rate (Totani 1997;Wijers et al 1998;Porciani & Madau 2001;Wang & Dai 2009, 2011a, the intergalactic medium metal enrichment (Barkana & Loeb 2004;Wang et al 2012), dark energy (Dai et al 2004;Friedman & Bloom 2005;Schaefer 2007;Basilakos & Perivolaropoulos 2008;Wang et al 2011b), reionization (Totani et al 2006;Gallerani et al 2008;Wang 2013), possible anisotropic acceleration (Wang & Wang 2014a), and the two-point correlation (Li & Lin 2015).…”

GRBs and Fundamental Physics

“…The association of long GRBs with core-collapse supernovae has been confirmed from observations in recent years (Stanek et al 2003;Hjorth et al 2003), which provides a complementary technique for measuring the high-redshift SFR (Totani 1997;Wijers et al 1998;Lamb & Reichart 2000;Porciani & Madau 2001;Bromm et al 2002). The selection effects should be considered (for a review, see Coward 2007).…”

“…Long GRBs formed by the collapse of massive stars, provide a complementary tools for measuring the SFR (Totani 1997;Wijers et al 1998;Bromm et al 2002). Because the lifetimes of massive stars are short, the formation rate can be treated as their death rate.…”