The Supernova–Gamma-Ray Burst Connection

TLDR

"GRB‑SNe exhibit higher kinetic energy and luminosity than ordinary supernovae, show considerable diversity, and carry most of their energy in nonrelativistic ejecta rather than relativistic jets, indicating that not all supernovae—nor all Type Ibc supernovae—produce GRBs." That is one sentence. Check sentence count: 3? Wait we have 3 sentences: Background, Purpose/Mechanism, Findings. But we have only 3 labels present?

Abstract

Observations show that at least some gamma-ray bursts (GRBs) happen simultaneously with core-collapse supernovae (SNe), thus linking by a common thread nature's two grandest explosions. We review here the growing evidence for and theoretical implications of this association, and conclude that most long-duration soft-spectrum GRBs are accompanied by massive stellar explosions (GRB-SNe). The kinetic energy and luminosity of well-studied GRB-SNe appear to be greater than those of ordinary SNe, but evidence exists, even in a limited sample, for considerable diversity. The existing sample also suggests that most of the energy in the explosion is contained in nonrelativistic ejecta (producing the supernova) rather than in the relativistic jets responsible for making the burst and its afterglow. Neither all SNe, nor even all SNe of Type Ibc produce GRBs. The degree of differential rotation in the collapsing iron core of massive stars when they die may be what makes the difference.