Quark-novae in neutron star - white dwarf binaries

a model for luminous (spin-down powered) sub-Chandrasekhar-mass Type Ia supernovae?

Rachid Ouyed, Jan Staff

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

We show that, by appealing to a Quark-Nova (QN) in a tight binary system containing a massive neutron star and a CO white dwarf (WD), a Type Ia explosion could occur. The QN ejecta collides with the WD, driving a shock that triggers carbon burning under degenerate conditions (the QN-Ia). The conditions in the compressed low-mass WD (MWD <0.9 M⊙) in our model mimic those of a Chandrasekhar mass WD. The spin-down luminosity from the QN compact remnant (the quark star) provides additional power that makes the QN-Ia light-curve brighter and broader than a standard SN-Ia with similar ⁵⁶Ni yield. In QNe-Ia, photometry and spectroscopy are not necessarily linked since the kinetic energy of the ejecta has a contribution from spin-down power and nuclear decay. Although QNe-Ia may not obey the Phillips relationship, their brightness and their relatively "normal looking" light-curves mean they could be included in the cosmological sample. Light-curve fitters would be confused by the discrepancy between spectroscopy at peak and photometry and would correct for it by effectively brightening or dimming the QNe-Ia apparent magnitudes, thus over- or under-estimating the true magnitude of these spin-down powered SNe-Ia. Contamination of QNe-Ia in samples of SNe-Ia used for cosmological analyses could systematically bias measurements of cosmological parameters if QNe-Ia are numerous enough at high-redshift. The strong mixing induced by spin-down wind combined with the low ⁵⁶Ni yields in QNe-Ia means that these would lack a secondary maximum in the i-band despite their luminous nature. We discuss possible QNe-Ia progenitors.
Original languageEnglish
Pages (from-to)435-464
Number of pages30
JournalResearch in Astronomy and Astrophysics
Volume13
Issue number4
DOIs
Publication statusPublished - 2013
Externally publishedYes

Keywords

  • stars: binary
  • stars: evolution
  • stars: neutron
  • stars: white dwarfs
  • supernovae: general

Fingerprint Dive into the research topics of 'Quark-novae in neutron star - white dwarf binaries: a model for luminous (spin-down powered) sub-Chandrasekhar-mass Type Ia supernovae?'. Together they form a unique fingerprint.

Cite this