Superluminous supernovae: 56Ni power versus magnetar radiation

Luc Dessart*, D. John Hillier, Roni Waldman, Eli Livne, St́ephane Blondin

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

172 Scopus citations

Abstract

Much uncertainty surrounds the origin of superluminous supernovae (SNe). Motivated by the discovery of the Type Ic SN 2007bi, we study its proposed association with a pair-instability SN (PISN). We compute stellar evolution models for primordial ~200M⊙ stars, simulating the implosion/explosion due to the pair-production instability, and use them as inputs for detailed non-local thermodynamic equilibrium time-dependent radiative transfer simulations that include non-local energy deposition and non-thermal processes. We retrieve the basic morphology of PISN light curves from red supergiant, blue supergiant and Wolf-Rayet (WR) star progenitors. Although we confirm that a progenitor 100M⊙ helium core (PISN model He100) fits well the SN 2007bi light curve, the low ratios of its kinetic energy and 56Ni mass to the ejecta mass, similar to standard core-collapse SNe, conspire to produce cool photospheres, red spectra subject to strong line blanketing and narrow-line profiles, all conflicting with SN 2007bi observations. He-core models of increasing 56Ni-to-ejecta mass ratio have bluer spectra, but still too red to match SN2007bi, even for model He125 - the effect of 56Ni heating is offset by the associated increase in blanketing. In contrast, the delayed injection of energy by a magnetar represents a more attractive alternative to reproduce the blue, weakly blanketed and broad-lined spectra of superluminous SNe. The extra heat source is free of blanketing and is not explicitly tied to the ejecta. Experimenting with an ~9M⊙ WR-star progenitor, initially exploded to yield an ~1.6 B SN Ib/c ejecta but later influenced by tunable magnetar-like radiation, we produce a diversity of blue spectral morphologies reminiscent of SN 2007bi, the peculiar Type Ib SN 2005bf and superluminous SN 2005ap-like events.

Original languageEnglish
Pages (from-to)L76-L80
JournalMonthly Notices of the Royal Astronomical Society: Letters
Volume426
Issue number1
DOIs
StatePublished - Oct 2012

Keywords

  • Evolution - stars
  • General - supernovae
  • Individual
  • Magnetars - supernovae
  • Radiative transfer - stars
  • SN2007bi, PTF 09atu

Fingerprint

Dive into the research topics of 'Superluminous supernovae: 56Ni power versus magnetar radiation'. Together they form a unique fingerprint.

Cite this