The Connection between Gamma-Ray Bursts and Extremely Metal-Poor Stars as Nucleosynthetic Probes of the Early Universe

TL;DR

This paper explores how different types of gamma-ray bursts and associated supernovae relate to the chemical abundance patterns in extremely metal-poor stars, suggesting a unified model involving jet-induced hypernova explosions of early stars.

Contribution

It proposes a unified nucleosynthesis model linking GRB diversity to abundance patterns in EMP stars through hyper-aspherical supernova explosions of Pop III stars.

Findings

High energy explosions explain normal EMP star abundances.

Low energy explosions account for CEMP and HMP star formation.

GRB-HNe and dark HNe form a continuum of BH-forming stellar deaths.

Abstract

The connection between the long GRBs and Type Ic Supernovae (SNe) has revealed the interesting diversity: (i) GRB-SNe, (ii) Non-GRB Hypernovae (HNe), (iii) X-Ray Flash (XRF)-SNe, and (iv) Non-SN GRBs (or dark HNe). We show that nucleosynthetic properties found in the above diversity are connected to the variation of the abundance patterns of extremely-metal-poor (EMP) stars, such as the excess of C, Co, Zn relative to Fe. We explain such a connection in a unified manner as nucleosynthesis of hyper-aspherical (jet-induced) explosions Pop III core-collapse SNe. We show that (1) the explosions with large energy deposition rate, $\dot{E}_{\rm dep}$, are observed as GRB-HNe and their yields can explain the abundances of normal EMP stars, and (2) the explosions with small $\dot{E}_{\rm dep}$ are observed as GRBs without bright SNe and can be responsible for the formation of the C-rich EMP (CEMP) and the hyper metal-poor (HMP) stars. We thus propose that GRB-HNe and the Non-SN GRBs (dark HNe) belong to a continuous series of BH-forming stellar deaths with the relativistic jets of different $\dot{E}_{\rm dep}$.