Questions tagged [white-dwarf]
Questions about electron degenerate stellar remnants.
15 questions
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Why does the Chandrasekhar limit affect white dwarfs differently?
The Chandrasekhar limit is the maximum mass of a stable white dwarf star. Beyond this, a carbon-oxygen white dwarf will typically explode in a type 1a supernova, due to the nuclear reactions at those ...
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How much mass will the Sun have when it becomes a white dwarf?
In 4 billion years, when our Sun sheds all of its outer gas layers and turns into a white dwarf, how much mass will the white dwarf have compared to what the sun has today?
Will the planets still ...
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Is there a possibility that a white dwarf can turn into a neutron star or a black hole?
I know that a white dwarf is supported mainly by electron degeneracy pressure and that if it gains more than about 1.4 solar masses from any source (such as a companion star or a collision), it ...
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The two channels of Type Ia SNe and their use as standard candles
As we know, Type Ia supernovae are used as standard candles since their absolute luminosities are expected to be roughly constant. The consensus model, as seen from the Wikipedia page, suggests this ...
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Will Sirius B start accreting from A and become a supernova type Ia?
Sirius B is a massive white dwarf of 1 Solar mass, orbiting at about 25 AU distance from the 2 Solar mass Sirius A. As it evolves and expands, will the A star start shedding matter to the white dwarf, ...
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How is the first detonation in Supernove type Ia triggered?
Ok, I read about the Supernova of type Ia and I found out that there are two detonations happening. First one is in helium shell around the white dwarf and second one seems to be triggered by the ...
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The colour of blue dwarf stars
The paper "M dwarfs: planet formation and long term evolution" describes blue dwarf stars, a hypothetical next-stage in the lifespan of red dwarf stars within a certain mass range, after which they ...
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Are white dwarf stars supported by proton degeneracy as well?
In general, fermions form a degenerate gas under high density or extremely low temperature. It's clear that white dwarf stars are supported by electron degeneracy pressure. However, there are still a ...
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Do all C-O white dwarfs have more-or-less the same proportions of carbon and oxygen?
Type 1a supernovae are known for having very consistent energy yields, and they are caused when a carbon-oxygen white dwarf reaches the Chandrasekhar limit of about 1.4 solar masses. Since type 1a ...
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What is considered "contact" for contact binary white dwarfs, and roughly how long can they stay that way before merging?
The question Why do they think that WDJ0551+4135 is “snowman shaped” i.e. a contact binary? has also raised the question of what a contact binary is or isn't, and how hard it might be to see one if it ...
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If a white dwarf collides with a giant star, could it create a TZO?
Thorne–Żytkow objects (TZOs) form from collisions between neutron stars and main sequence or giant stars. Ultimately, the neutron star becomes the "core" of the giant star.
However, could this also ...
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How small stars help with planet formation
As I understood, low mass stars in their core go through fusion, but only the fusion of hydrogen happens. When it depletes hydrogen, fusion stops as temperature is still not high enough to support ...
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What crystal structures are predicted for the crystalline phase of matter inside crystalizing white dwarfs? Does it depend on the carbon/oxygen ratio?
The abstract of Venner et al. (2023) A Crystallizing White Dwarf in a Sirius-Like Quadruple System includes the following:
The location of HD 190412 C on the 𝑇eff − mass diagram implies it is ...
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What determines the temperature of a white dwarf?
Can someone please explain what determines the temperature of the white dwarf? Is more massive white dwarf hotter ? Also, is the density of a white dwarf always a constant?
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Do white dwarfs lose mass as they fade to black dwarfs? Is there a correlation between temperature, mass, and radius?
I'm having a difficult time understanding certain behaviors of white dwarfs.
I understand how mass is lost in the red giant to white dwarf transition process. I understand that white dwarfs can ...
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