3D Hydrodynamical Simulations of Helium-Ignited Double-degenerate White Dwarf Mergers
| Autor: | Niranjan C. Roy, Vishal Tiwari, Alexey Bobrick, Daniel Kosakowski, Robert Fisher, Hagai B. Perets, Rahul Kashyap, Pablo Lorén-Aguilar, Enrique García-Berro |
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| Přispěvatelé: | Universitat Politècnica de Catalunya. Departament de Física, Universitat Politècnica de Catalunya. GAA - Grup d'Astronomia i Astrofísica |
| Jazyk: | angličtina |
| Rok vydání: | 2022 |
| Předmět: |
Type Ia supernovae
High Energy Astrophysical Phenomena (astro-ph.HE) FOS: Physical sciences Astronomy and Astrophysics Estels nans Camps magnètics solars Astrophysics - Solar and Stellar Astrophysics Space and Planetary Science Hydrodynamics Stars--Magnetic fields Stellar mergers Nuclear astrophysics Aeronàutica i espai [Àrees temàtiques de la UPC] Astrophysics - High Energy Astrophysical Phenomena White dwarf stars Solar and Stellar Astrophysics (astro-ph.SR) |
| Zdroj: | UPCommons. Portal del coneixement obert de la UPC Universitat Politècnica de Catalunya (UPC) |
| Popis: | The origins of type Ia supernovae (SNe Ia) are still debated. Some of the leading scenarios involve a double detonation in double white dwarf (WD) systems. In these scenarios, helium shell detonation occurs on top of a carbon-oxygen (CO) WD, which then drives the detonation of the CO-core, producing a SN Ia. Extensive studies have been done on the possibility of a double helium detonation, following a dynamical helium mass-transfer phase onto a CO-WD. However, 3D self-consistent modeling of the double-WD system, the mass transfer, and the helium shell detonation have been little studied. Here we use 3D hydrodynamical simulations to explore this case in which a helium detonation occurs near the point of Roche lobe overflow of the donor WD and may lead to an SN Ia through the dynamically driven double-degenerate double-detonation (D6) mechanism. We find that the helium layer of the accreting primary WD does undergo a detonation, while the underlying carbon-oxygen core does not, leading to an extremely rapid and faint nova-like transient instead of a luminous SN Ia event. This failed core detonation suggests that D6 SNe Ia may be restricted to the most massive carbon-oxygen primary WDs. We highlight the nucleosynthesis of the long-lived radioisotope $^{44}$Ti during explosive helium burning, which may serve as a hallmark both of successful as well as failed D6 events which subsequently detonate as classical double-degenerate mergers. 11 pages, 4 figures, 1 table. Published in the Astrophysical Journal Letters |
| Databáze: | OpenAIRE |
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