Smoothed particle hydrodynamics simulations of the core-degenerate scenario for Type Ia supernovae

The core-degenerate scenario for Type Ia supernovae involves the merger of the hot core of an asymptotic giant branch star and a white dwarf, and might contribute a non-negligible fraction of all thermonuclear supernovae. Despite its potential interest, very few studies, and based on only crude simp...

ver descrição completa

Detalhes bibliográficos
Autores: Aznar Siguan, Gabriela, García-Berro Montilla, Enrique|||0000-0002-1623-5838, Lorén Aguilar, Pablo, Soker, Noam, Kashi, Amit
Formato: artículo
Fecha de publicación:2015
País:España
Recursos:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/81353
Acesso em linha:https://hdl.handle.net/2117/81353
https://dx.doi.org/10.1093/mnras/stv824
Access Level:acceso abierto
Palavra-chave:White dwarf stars
Supernovae
hydrodynamics
stars: AGB and post-AGB
binaries: close
supernovae: general
white dwarfs
ACCRETING WHITE-DWARFS
DYNAMICAL INTERACTIONS
SURFACE DETONATIONS
HELIUM DETONATIONS
CARBON IGNITION
MERGER REMNANTS
TRIPLE-SYSTEMS
RAY-BURSTS
EVOLUTION
PROGENITORS
Estels nans
Supernoves
Àrees temàtiques de la UPC::Física::Astronomia i astrofísica
Descrição
Resumo:The core-degenerate scenario for Type Ia supernovae involves the merger of the hot core of an asymptotic giant branch star and a white dwarf, and might contribute a non-negligible fraction of all thermonuclear supernovae. Despite its potential interest, very few studies, and based on only crude simplifications, have been devoted to investigate this possible scenario, compared with the large efforts invested to study some other scenarios. Here we perform the first three-dimensional simulations of the merger phase, and find that this process can lead to the formation of a massive white dwarf, as required by this scenario. We consider two situations, according to the mass of the circumbinary disc formed around the system during the final stages of the common envelope phase. If the disc is massive enough, the stars merge on a highly eccentric orbit. Otherwise, the merger occurs after the circumbinary disc has been ejected and gravitational wave radiation has brought the stars close enough for the secondary to overflow its Roche lobe radius. Not surprisingly, the overall characteristics of the merger remnants are similar to those found for the double-degenerate scenario, independently of the very different core temperature and of the orbits of the merging stars. They consist of a central massive white dwarf, surrounded by a hot, rapidly rotating corona and a thick debris region.