Mixing fraction in classical novae

Abstract

Context. Classical novae are powered by thermonuclear runaways occurring on the surface of accreting white dwarfs (WDs). In the observations, the enrichments of heavy elements in nova ejecta have been detected, indicating a mixing process between the accreted matter and the matter from the outer layers of the underlying WDs prior to nova outbursts. However, the mixing fraction in classical novae is still uncertain. Aims. The purpose of this article is to investigate some elemental abundance ratios during nova outbursts that can be used to estimate the WD mixing fraction in classical novae. Methods. By considering different WD mixing fractions with the stellar evolution code Modules for Experiments in Stellar Astrophysics (MESA), we carried out a series of simulations of nova outbursts, in which the initial CO WD masses range from $0.7-1.0M_{\odot }$. Results. We identified four elemental abundance ratios (i.e. $(\mathrm{H}+\mathrm{He})/\sum \mathrm{CNO}$, $(\mathrm{H}+\mathrm{He})/Ne$, $\sum CNO/Mg,$ and $\sum CNO/Si$) that satisfy the conditions for determining the WD mixing fraction, in which $(\mathrm{H}+\mathrm{He})/\sum \mathrm{CNO}$ is the most suitable mixing meter. We also estimated the WD mixing fraction in some representative classical novae. Additionally, we found that a higher metallicity (i.e. higher WD mixing fraction) is preferentially accompanied by a longer $t_2$ (the time of decline by two magnitudes from peak luminosity) during nova outbursts. Our results can be used to constrain the mixing process in classical novae.

arXiv comment14 pages, 6 figures, 2 tables, accepted for publication in A&A

References in corpus (29)

• Modules for Experiments in Stellar Astrophysics (MESA)
• Modules for Experiments in Stellar Astrophysics (MESA): Giant Planets, Oscillations, Rotation, and Massive Stars
• Modules for Experiments in Stellar Astrophysics (MESA): Binaries, Pulsations, and Explosions
• Modules for Experiments in Stellar Astrophysics (MESA): Convective Boundaries, Element Diffusion, and Massive Star Explosions
• An Extended Grid of Nova Models: II. The Parameter Space of Nova Outbursts
• Nucleosynthesis in Classical Novae: ONe vs. CO White Dwarfs
• Hydrogen Burning on Accreting White Dwarfs: Stability, Recurrent Novae, and the Post-Novae Supersoft Source
• Evolution of 3-9 Mo Stars for Z=0.001 - 0.03 and Metallicity Effects on Type Ia Supernovae
• Mass-accreting white dwarfs and type Ia supernovae
• How the merger of two white dwarfs depends on their mass ratio: orbital stability and detonations at contact
• MESA Models of Classical Nova Outbursts: The Multicycle Evolution and Effects of Convective Boundary Mixing
• On the C/O Enrichment of Novae Ejecta
• On Heavy Element Enrichment in Classical Novae
• Nuclear Thermometers for Classical Novae
• MESA and NuGrid simulations of classical novae: CO and ONe nova nucleosynthesis
• The formation of neutron star systems through accretion-induced collapse in white-dwarf binaries
• Light Curve Analysis of Neon Novae
• On mixing at the core-envelope interface during classical nova outbursts
• Nuclear Mixing Meters for Classical Novae
• Comprehensive models of novae at metallicity $Z=0.02$ and $Z=10^{-4}$
• Mass retention efficiencies of He accretion onto carbon-oxygen white dwarfs and type Ia supernovae
• The Sensitivity of Multidimensional Nova Calculations to the Outer Boundary Conditions
• Super-Eddington wind scenario for the progenitors of type Ia supernovae: Accreting He-rich matter onto white dwarfs
• Two-dimensional simulations of mixing in classical novae: the effect of the white dwarf composition and mass
• Synthesis of C-rich dust in CO nova ourbursts
• A Theory for the Maximum Magnitude versus Rate of Decline (MMRD) Relation of Classical Novae
• Merging of a CO WD and a He-rich white dwarf to produce a type Ia supernovae
• He-shell flashes on the surface of oxygen-neon white dwarfs
• Helium enrichment during classical nova outbursts

Cited by in corpus (5)

• Binary Stars in the New Millennium
• Binary Interaction Dominates Mass Ejection in Classical Novae
• The multi-wavelength view of shocks in the fastest nova V1674 Her
• Physics of nova outbursts: A theoretical model of classical nova outbursts with self-consistent wind mass loss
• Exploring the archives: A search for novae in UVIT snapshots of M31