Nuclear and dark matter heating in massive white dwarf stars

Abstract

Recently, Cheng et al. identified a number of massive white dwarfs (WD) that appear to have an additional heat source providing a luminosity near $\approx 10^{-3}{L}_{\odot }$ for multiple Gyr. In this paper we explore heating from electron capture and pycnonuclear reactions. We also explore heating from dark matter annihilation. WD stars appear to be too small to capture enough dark matter for this to be important. Finally, if dark matter condenses to very high densities inside a WD this could ignite nuclear reactions. We calculate the enhanced central density of a WD in the gravitational potential of a very dense dark matter core. While this might start a supernova, it seems unlikely to provide modest heating for a long time. We conclude that electron capture, pycnonuclear, and dark matter reactions are unlikely to provide significant heating in the massive WD that Cheng considers.

5 pages, 3 figures

References in corpus (9)

• Compact Stars as Dark Matter Probes
• Fusion reactions in multicomponent dense matter
• The Physics of Crystallization from Globular Cluster White Dwarf Stars in NGC 6397
• Dark Matter Capture in the First Stars: a Power Source and Limit on Stellar Mass
• Fusion of neutron rich oxygen isotopes in the crust of accreting neutron stars
• Diffusion of Neon in White Dwarf Stars
• Evolution and dynamical properties of Bose-Einstein condensate dark matter stars
• Toward Precision Cosmochronology: A New C/O Phase Diagram for White Dwarfs
• Indirect Probes of Dark Matter and Globular Cluster Properties From Dark Matter Annihilation within the Coolest White Dwarfs

Cited by in corpus (19)

• Observing the thermalization of dark matter in neutron stars
• ${}^{22}$Ne Phase Separation As A Solution To The Ultramassive White Dwarf Cooling Anomaly
• Accelerating Composite Dark Matter Discovery with Nuclear Recoils and the Migdal Effect
• Forever young white dwarfs: when stellar ageing stops
• The evolution of ultra-massive carbon oxygen white dwarfs
• Constraining Dark Matter properties with the first generation of stars
• White dwarf stars in modified gravity
• Multicomponent multiscatter capture of Dark Matter
• Giant planet formation in Palatini gravity
• Analytic Approximations for the Velocity Suppression of Dark Matter Capture
• The origin of ultramassive white dwarfs: hints from Gaia EDR3
• Triggering Electron Capture Supernovae: Dark Matter Effects in Degenerate White-Dwarf-like Cores of Super-Asymptotic Giant Branch Stars
• White Dwarf Stars in the Big Data Era
• Deep Inelastic Scattering in the Capture of Dark Matter by Neutron Stars
• Charged anisotropic white dwarfs in $f\left(R,T\right)$ gravity
• Supermassive Dark Stars and their remnants as a possible solution to three recent cosmic dawn puzzles
• Effects of light-mass fermionic dark matter on the equilibrium and stability of white dwarfs
• Constraining Asymmetric DM Properties by Black Hole Formation in Neutron Stars and Population III Stars
• Revisiting constraints on asymmetric dark matter from collapse in white dwarf stars