The pulsational properties of ultra-massive DB white dwarfs with carbon-oxygen cores coming from single-star evolution

Abstract

Ultra-massive white dwarfs are relevant for their role as type Ia Supernova progenitors, the occurrence of physical processes in the asymptotic giant-branch phase, the existence of high-field magnetic white dwarfs, and the occurrence of double white dwarf mergers. Some hydrogen-rich ultra-massive white dwarfs are pulsating stars, and as such, they offer the possibility of studying their interiors through asteroseismology. On the other hand, pulsating helium-rich ultra-massive white dwarfs could be even more attractive objects for asteroseismology if they were found, as they should be hotter and less crystallized than pulsating hydrogen-rich white dwarfs, something that would pave the way for probing their deep interiors. We explore the pulsational properties of ultra-massive helium-rich white dwarfs with carbon-oxygen and oxygen-neon cores resulting from single stellar evolution. Our goal is to provide a theoretical basis that could eventually help to discern the core composition of ultra-massive white dwarfs and the scenario of their formation through asteroseismology, anticipating the possible future detection of pulsations in this type of stars. We find that, given that the white dwarf models coming from the three scenarios considered are characterized by distinct core chemical profiles, their pulsation properties are also different, thus leading to distinctive signatures in the period-spacing and mode-trapping properties. Our results indicate that, in case of an eventual detection of pulsating ultra-massive helium-rich white dwarfs, it would be possible to derive valuable information encrypted in the core of these stars in connection with the origin of such exotic objects. The detection of pulsations in these stars has many chances to be achieved soon through observations collected with ongoing space missions.

arXiv comment8 pages, 10 figures. To be published in A&A. arXiv admin note: text overlap with arXiv:2011.10439

References in corpus (58)

• The Sloan Digital Sky Survey: Technical Summary
• The Transiting Exoplanet Survey Satellite
• SDSS DR7 White Dwarf Catalog
• Evolutionary and pulsational properties of white dwarf stars
• Post-Asymptotic Giant Branch Evolution of Low- and Intermediate-Mass Stars. Preliminary Results
• New models for the evolution of Post-Asymptotic Giant Branch stars and Central Stars of Planetary Nebulae
• Pulsating White Dwarf Stars and Precision Asteroseismology
• On the Spectral Evolution of Hot White Dwarf Stars. I. A Detailed Model-Atmosphere Analysis of Hot White Dwarfs from SDSS DR12
• New white dwarf and subdwarf stars in the Sloan Digital Sky Survey Data Release 12
• The formation and evolution of hydrogen-deficient post-AGB white dwarfs: the emerging chemical profile and the expectations for the PG1159-DB-DQ evolutionary connection
• The Long-Term Evolution of Double White Dwarf Mergers
• Pulsating white dwarfs: new insights
• The binarity of the local white dwarf population
• Super-AGB Stars and their role as Electron Capture Supernova progenitors
• Core crystallization and pile-up in the cooling sequence of evolving white dwarfs
• The 100 pc White Dwarf Sample in the SDSS Footprint
• A White Dwarf catalogue from Gaia-DR2 and the Virtual Observatory
• On the evolution of ultra-massive white dwarfs
• The Effect of Crystallization on the Pulsations of White Dwarf Stars
• White dwarf and subdwarf stars in the Sloan Digital Sky Survey Data Release 14
• Asteroseismic inferences on GW Vir variable stars in the frame of new PG 1159 evolutionary models
• Comparison of theoretical white dwarf cooling timescales
• New evolutionary models for massive ZZ Ceti stars: I. First results for their pulsational properties
• White dwarf evolutionary sequences for low-metallicity progenitors: The impact of third dredge-up
• Crystallization of Carbon Oxygen Mixtures in White Dwarf Stars
• Fundamental parameter accuracy of DA and DB white dwarfs in Gaia Data Release 2
• The separation distribution and merger rate of double white dwarfs: improved constraints
• Looks can be deceiving: underestimating the age of single white dwarfs due to binary mergers
• Evolutionary Models for the Remnant of the Merger of Two Carbon-Oxygen Core White Dwarfs
• On The Evolution of Magnetic White Dwarfs
• Whole Earth Telescope observations of BPM 37093: a seismological test of crystallization theory in white dwarfs
• Crystallization of classical multi-component plasmas
• New white dwarf envelope models and diffusion. Application to DQ white dwarfs
• Double white dwarf merger products among high-mass white dwarfs
• Multi-Gigayear White Dwarf Cooling Delays from Clustering-Enhanced Gravitational Sedimentation
• The Aarhus Red Giants Challenge I: Stellar structures in the red giant branch phase
• Discovery of an ultramassive pulsating white dwarf
• Diffusive Nuclear Burning of Helium on Neutron Stars
• The formation of ultra-massive carbon-oxygen core white dwarfs and their evolutionary and pulsational properties
• Four New Massive Pulsating White Dwarfs Including an Ultramassive DAV
• New evolutionary models for massive ZZ Ceti stars. II. The effects of crystallization on their pulsational properties
• Discovery of a hot ultramassive rapidly rotating DBA White Dwarf
• Pulsations of massive ZZ Ceti stars with carbon/oxygen and oxygen/neon cores
• New developments of the ZZ Ceti instability strip: The discovery of eleven new variables
• Diffusion and Coulomb separation of ions in dense matter
• A Young Ultramassive White Dwarf in the AB Doradus Moving Group
• The Aarhus red giants challenge II. Stellar oscillations in the red giant branch phase
• Pulsation properties of ultra-massive DA white dwarf stars with ONe cores
• Detections and Constraints on White Dwarf Variability from Time-Series GALEX Observations
• Analysis of cool DO-type white dwarfs from the Sloan Digital Sky Survey Data Release 10
• The double-layered chemical structure in DB white dwarfs
• Asteroseismological analysis of the ultra-massive ZZ Ceti stars BPM~37093, GD~518, and SDSS~J0840+5222
• New DA white dwarf evolutionary models and their pulsational properties
• On the existence of warm H-rich pulsating white dwarfs
• An in-depth reanalysis of the alleged type Ia supernova progenitor Henize 2-428
• The asteroseismic potential of CHEOPS
• A Massive Magnetic Helium Atmosphere White Dwarf Binary in a Young Star Cluster
• The impact of Coulomb diffusion of ions on the pulsational properties of DA white dwarfs

Cited by in corpus (4)

• Formation of ultra-massive carbon-oxygen white dwarfs from the merger of carbon-oxygen and helium white dwarf pairs
• The evolution of ultra-massive carbon oxygen white dwarfs
• WD J004917.14$-$252556.81, the Most Massive Pulsating White Dwarf
• Can we reveal the core-chemical composition of ultra-massive white dwarfs through their magnetic fields?