NUCLEOSYNTHESIS DURING THE MERGER OF WHITE DWARFS AND THE ORIGIN OF R CORONAE BOREALIS STARS

作者：Longland R^*; Loren Aguilar P; Jose J; Garcia Berro E; Althaus L G; Isern J

来源：Astrophysical Journal Letters, 2011, 737(2): L34.

DOI：10.1088/2041-8205/737/2/L34

• nuclear reactions, nucleosynthesis, abundances
• stars: AGB and post-AGB
• white dwarfs

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-circle dot helium white dwarf with a 0.8 M-circle dot 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.

• 出版日期2011-8-20