Nucleosynthesis during the merger of white dwarfs and the origin of R Coronae Borealis stars

Many hydrogen-deficient stars are characterized by surface abundance patterns that are hard to reconcile with conventional stellar evolution. Instead, it has been suggested that they may represent the result of a merger episode between a helium and a carbon-oxygen white dwarf. In this Letter, we pre...

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Detalles Bibliográficos
Autores: Longland, Richard, Loren Aguilar, P., Jose, J., Garcia Berro, E., Althaus, Leandro Gabriel, Isern, J.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2011
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/10281
Acceso en línea:http://hdl.handle.net/11336/10281
Access Level:acceso abierto
Palabra clave:Nuclear Reactions
Nucleosynthesis
Agb Stars
White Dwarfs
https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
Descripción
Sumario:Many hydrogen-deficient stars are characterized by surface abundance patterns that are hard to reconcile with conventional stellar evolution. Instead, it has been suggested that they may represent the result of a merger episode between a helium and a carbon-oxygen white dwarf. In this Letter, we present a nucleosynthesis study of the merger of a 0.4 M ☉ helium white dwarf with a 0.8 M ☉ carbon-oxygen white dwarf, by coupling the thermodynamic history of Smoothed Particle Hydrodynamics particles with a post-processing code. The resulting chemical abundance pattern, particularly for oxygen and fluorine, is in qualitative agreement with the observed abundances in R Coronae Borealis stars.