Related Progenitor Models for Long-duration Gamma-Ray Bursts and Type Ic Superluminous Supernovae

Abstract

We model the late evolution and mass loss history of rapidly rotating Wolf-Rayet stars in the mass range 5 M . . . 100 M . We find that quasi-chemically homogeneously evolving single stars computed with enhanced mixing retain very little or no helium and are compatible with Type Ic supernovae. The more efficient removal of core angular momentum and the expected smaller compact object mass in our lower mass models lead to core spins in the range suggested for magnetar driven superluminous supernovae. Our more massive models retain larger specific core angular momenta, expected for long-duration gamma-ray bursts in the collapsar scenario. Due to the absence of a significant He envelope, the rapidly increasing neutrino emission after core helium exhaustion leads to an accelerated contraction of the whole star, inducing a strong spin-up, and centrifugally driven mass loss at rates of up to 10 −2 M yr −1 in the last years to decades before core collapse. Since the angular momentum transport in our lower mass models enhances the envelope spin-up, they show the largest relative amounts of centrifugally enforced mass loss, i.e., up to 25% of the expected ejecta mass. Our most massive models evolve into the pulsational pair-instability regime. We would thus expect signatures of interaction with a C/O-rich circumstellar medium for Type Ic superluminous supernovae with ejecta masses below ∼ 10 M and for the most massive engine-driven explosions with ejecta masses above ∼ 30 M . Signs of such interaction should be observable at early epochs of the supernova explosion, and may be related to bumps observed in the light curves of superluminous supernovae, or to the massive circumstellar CO-shell proposed for Type Ic superluminous supernova Gaia16apd.

SN 2016iet: The Pulsational or Pair Instability Explosion of a Low-metallicity Massive CO Core Embedded in a Dense Hydrogen-poor Circumstellar Medium

“…In particular, PPISN models in the range of masses inferred here can indeed eject about half of their CO core mass, but are predicted to do so thousands of years before explosion (Woosley 2017), not in less than a decade, as required for SN 2016iet. Additional mass loss may occur in the final years before the final core collapse, but at a level of only a few M (Woosley 2017;Aguilera-Dena et al 2018), an order of magnitude too low for SN 2016iet. Finally, Woosley (2017) also argue that the remaining cores of ∼ 35 − 45 M have a large binding energy that may make them difficult to explode, and lead instead of massive black holes; this is again in tension with the inferred ejecta mass of ∼ 20 − 85 M for SN 2016iet.…”

“…These pulses can lead to shell collisions that power a SN-like transient -a PPISN -while the inner layers contract and temporarily resume stable burning (Woosley et al 2007). The ejecta produced in the ultimate core collapse explosion (if successful) can also interact with shells ejected ∼ 10 4 years prior, powering a luminous and long lasting SN (Woosley et al 2007;Aguilera-Dena et al 2018). There are several observed SNe with unusual photometric or spectroscopic features that have been interpreted as signs of PPISNe.…”

Highly luminous supernovae associated with gamma-ray bursts

“…We also note this model uses a BH central engine. Aguilera-Dena et al (2018) have presented evolutionary models of potential Type Ic progenitor stars that reach large C/O-core masses via enhanced mixing. Depending on the core mass, they found a continuum spanning from Type Ic SLSNe over magnetar-powered GRB-SNe, BH powered GRB-SNe up to PPI-SNe.…”

The Type II superluminous SN 2008es at late times: near-infrared excess and circumstellar interaction

“…For SN 2008es, the estimated mass-loss rate is consistent with that of a giant eruption. Other proposed extreme mass-loss mechanisms include hydrodynamic instabilities (Smith & Arnett 2014), gravity-wave-driven mass loss (Shiode & Quataert 2014), or centrifugal-driven mass loss of spun-up Wolf-Rayet stars (Aguilera-Dena et al 2018), which might be more related to the hydrogen-poor events rather than to the hydrogen-rich ones.…”