The supernova–gamma-ray burst–jet connection

Abstract

The observed association between supernovae and gamma-ray bursts represents a cornerstone in our understanding of the nature of gamma-ray bursts. The collapsar model provides a theoretical framework for this connection. A key element is the launch of a bipolar jet (seen as a gamma-ray burst). The resulting hot cocoon disrupts the star, whereas the 56 Ni produced gives rise to radioactive heating of the ejecta, seen as a supernova. In this discussion paper, I summarize the observational status of the supernova–gamma-ray burst connection in the context of the ‘engine’ picture of jet-driven supernovae and highlight SN 2012bz/GRB 120422A—with its luminous supernova but intermediate high-energy luminosity—as a possible transition object between low-luminosity and jet gamma-ray bursts. The jet channel for supernova explosions may provide new insights into supernova explosions in general.

Properties of long gamma-ray bursts from massive compact binaries

“…There is strong observational evidence for a correlation between long-duration gamma-ray bursts and type Ibc supernovae [1,2]. This fits with a model closely related to that of Woosley [3], in which the burst forms through the accretion of roughly a Solar mass of material onto a newly formed black hole, though an accretion disc that forms during the core collapse of a massive star.…”

Spatially-resolved dust properties of the GRB 980425 host galaxy

“…Hjorth et al 2003;Stanek et al 2003; for a review see Hjorth & Bloom 2012), and therefore signal very recent star formation in their host galaxies. This is also supported by the detection of the signatures of Wolf-Rayet (WR) stars in GRB hosts (Hammer et al 2006;Han et al 2010; but see Chen et al 2007;Schulze et al 2011), by very low ages of the GRB sites (Christensen et al 2008;Thöne et al 2008;Östlin et al 2008), and by the concentration of GRBs in the UV-brightest pixels of their hosts (Bloom et al 2002;Fruchter et al 2006;Kelly et al 2008), similar to that of WR stars and supernovae Ic (Leloudas et al 2010).…”

Failed Collapsar Jets to Explain Low Luminosity GRB Properties

“…Angular and energetic properties suggest that brief engines (with T inj < T breakout , either due to short T inj or large θ 0 ) represent excellent models to explain the debated llGRBs. In particular, brief engines' jets display two of llGRBs peculiar, and hard to explain, features: 1) an estimated llGRBs rate ~100 times higher than that of GRBs [3,4,5] and, 2) a potentially energetic SN emission ~ 10 51-52 erg [6] (as most of these failed jets' are not well collimated and expands with sub-relativistic velocities). These two features only arise from brief engines.…”

“…2) Strong and clear SN connection, in contrast with the typically SN-less GRBs. Furthermore, while llGRBs are sub energetic, the SNe associated with them are extremely energetic and rare (Broad Line SN type; ~10 52 erg): GRB 980425/1998bw, GRB 031203/2003lw, GRB 100316D/2010bh & GRB 120422A/2012bz [6]. In order to explain llGRBs together with GRBs in a one global picture, we present numerical simulations of diverse collapsars.…”

“…Our results show that the expanding jet's hydrodynamical properties significantly differ, in particular outflow collimation and relativistic acceleration. The implication of this is that brief engines (with T inj < T breakout , either due to a short T inj or to a large θ 0 ) represent excellent systems to explain the debated low-luminosity GRBs (llGRBs), displaying two of llGRBs peculiar features: i) the estimated llGRBs rate at least about 100 times higher than that of GRBs [3,4,5], and ii) potentially energetic SN emission [6]. We find that these two features only arise from brief engines.…”