22Ne Phase Separation as a Solution to the Ultramassive White Dwarf Cooling Anomaly
نویسندگان
چکیده
منابع مشابه
Gravitational Settling of 22ne in Liquid White Dwarf Interiors
The nuclear reactions that occur in the stellar progenitors of white dwarfs (WDs) lead to an internal composition of 12C, 16O, and a “contaminant” nucleus, 22Ne . The 22Ne is produced by helium captures on 14N left from hydrogen burning via the CNO cycle. By virtue of its two excess neutrons (relative to the predominant A = 2Z nuclei), a downward force of ≈ 2mpg is exerted on 22Ne in the WD int...
متن کاملThe Puzzling White Dwarf Cooling Sequence in NGC 6791: A Simple Solution
In this paper we demonstrate that the puzzling bright peak in the luminosity function of the white dwarf (WD) cooling sequence of NGC 6791 can be naturally accounted for if ∼ 34% of the observed WDs are WD+WD binary systems. Subject headings: open clusters and associations: individual (NGC 6791) — white dwarfs
متن کاملWhite dwarf cooling and large extra dimensions
Theories of fundamental interactions with large extra dimensions have recently become very popular. Astrophysical bounds from the Sun, red-giants and SN1987a have already been derived by other authors for the theory proposed by Arkani-Hamed, Dimopoulos and Dvali. In this paper we consider G117-B15A pulsating white dwarf (ZZ Ceti star) for which the secular rate at which the period of its fundam...
متن کاملWhite Dwarf cooling Sequences, II: luminosity functions
Context. Given the importance of white dwarfs (WDs) in many fields of modern astrophysics, the precise knowledge of the actual degree of accuracy of the associated theoretical predictions is a primary task. In the first paper of a series dedicated to the modeling of WD structure and evolution we discussed the limits of the available theoretical studies of cooling sequences. Aims. In the present...
متن کاملWhite Dwarf Heating and Subsequent Cooling in Dwarf Nova Outbursts
We follow the time dependent thermal evolution of a white dwarf (WD) undergoing sudden accretion in a dwarf nova outburst, using both simulations and analytic estimates. The post-outburst lightcurve clearly separates into early times when the WD flux is high, and late times when the flux is near the quiescent level. The break between these two regimes, occurring at a time of order the outburst ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: The Astrophysical Journal Letters
سال: 2021
ISSN: 2041-8205,2041-8213
DOI: 10.3847/2041-8213/abf14b