Population synthesis of triple systems in the context of mergers of carbon–oxygen white dwarfs

摘要: Hierarchical triple systems are common among field stars yet their long-term evolution is poorly understood theoretically. In such Kozai cycles can be induced in the inner binary system during which orbit eccentricity and inclination between both orbits vary periodically. These cycles, combined with tidal friction gravitational wave emission, significantly affect evolution. To investigate these effects quantitatively we perform a population synthesis study of focus on evolutionary paths that lead to mergers carbon-oxygen (CO) white dwarfs (WDs), constitute an important candidate progenitor channel for type Ia supernovae (SNe Ia). We approach this problem by Monte Carlo sampling from observation-based distributions within primary mass range 1.0 - 6.5 M_Sun semi-major axes a_1 eccentricities e_1 satisfying (1-e_1^2) > 12 AU, i.e. non-interacting absence tertiary component. evolve means newly developed algorithm couples secular dynamics existing code. find alters about 24% all sampled systems. particular, several channels leading CO WD mergers. Amongst novel collision occurs wide as result extremely high cycles. With assumptions SN explosion estimate SNe delay time distribution resulting triples compare observations. Although our rate low, have determined lower limit triple-induced further needed includes initially tighter orbits.