All Questions
Tagged with white-dwarf neutron-star
19 questions
6
votes
2
answers
1k
views
What are the most up to date, accepted, evolution stages of big stars that end in compact objects or a planetary nebula?
There are numerous charts and diagrams showing the stages of stellar evolution, as:
or
among many more (you can find several after googling a little), for example.
When I studied my B.Sc. on Physics,...
- 201
4
votes
1
answer
96
views
Degenerate object accretion - what happens after it becomes a PMO?
Degenerate objects such as neutron stars and white dwarfs can be accreted from by other objects. As the degenerate object loses mass, it could pass through different mass ranges which govern the ...
- 6,733
2
votes
1
answer
185
views
What is the maximum radius of a pure iron-56 planet?
Suppose we are building a pure iron-56 planet atom by atom, how large can it get in terms of radius before it collapses into a black hole?
- 123
6
votes
1
answer
257
views
Do “neutrino supernovae” exist?
Core collapse supernovae release most of their energy in the form of neutrinos. About 1% of the neutrinos are absorbed by the thick outer envelope which powers a spectacular supernova explosion.
Core ...
- 285
5
votes
1
answer
101
views
What is the spectral reflection curve of cold white dwarfs and neutron stars?
Suppose that I got a white dwarf and a neutron star and after some trillions of years their temperature are down to just a few °K so cold that they don't emit any appreciable black body radiation.
Now,...
- 1,064
1
vote
2
answers
179
views
What does an electron-capture supernova leave behind? A white dwarf, a neutron star or nothing?
Somehow, none of the many articles I've read about the recent discovery of electron-capture supernovae has specifically said what they leave behind as remnants.....
- 5,585
1
vote
1
answer
93
views
Is something wrong with my luminosity calculation?
A few million years after a white dwarf forms, its surface temperature reaches $100000\text{K}$, while its radius is $0.01R_\odot$. Would this mean that its luminosity is $\Big(\dfrac{100000}{5778}\...
- 6,733
3
votes
0
answers
55
views
Can mass loss via accretion occur on stellar remnants?
We know that normal stars can lose mass to a binary companion. But can this happen to neutron stars and white dwarfs? Let's say a stellar black hole is being orbited by a white dwarf or neutron star. ...
2
votes
0
answers
115
views
What would happen if a neutron star merged with a white dwarf?
We've heard of neutron star mergers and white dwarf mergers. But what would result in a neutron star merging with a white dwarf? Would there be a similar super/kilonova, are there any examples of it, ...
3
votes
1
answer
774
views
Assuming proton decay is false, what's the ultimate fate of a neutron star or white dwarf?
A still unproven theory that protons can decay, and have a halflife of $10^{30}$ years or so, meaning eventually all matter will dissolve because their constituent protons and therefore neutrons will ...
2
votes
1
answer
111
views
Is the object a pulsar
We have a star having 1.8 solar mass. Justify any four means (measurable/ observed properties) by which you can identify that the object is a Pulsar and not a white dwarf or a Black Hole.
So one ...
13
votes
5
answers
4k
views
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 ...
- 251
0
votes
2
answers
535
views
Is the lower mass limit of a neutron star the same as the upper mass limit of a white dwarf?
If not, when can a white dwarf be more massive than a neutron star?
- 2,249
3
votes
2
answers
865
views
Cosmic events as standard candles
Type 1a supernovae are used as standard candles. Are there other high energy cosmic events which can be used as standard candles. For example, collapse of neutron star into a black hole is also ...
- 528
8
votes
2
answers
2k
views
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 ...
- 8,186
6
votes
3
answers
961
views
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 ...
- 8,186
4
votes
3
answers
527
views
Can life survive on the equator of cooled and fast rotating white dwarf or neutron star?
As I know, some stars produces carbon, nitrogen and oxygen when they are old and become white dwarfs or neutron stars. And even their surface gravity is strong, it may rotate very fast so that the ...
- 2,249
1
vote
4
answers
8k
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What is the difference between a neutron star and a white dwarf?
What is the difference between a neutron star and a white dwarf? I know that both are very dense even if they go through different phases.
- 353
13
votes
2
answers
2k
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How do stellar temperatures vary?
The temperature of the surface of the Sun (photosphere) is between 4500° - 6000° Kelvin. Inside the core, it's around 15.7 million degrees Kelvin.
In other types of stars (neutron stars, white ...
- 2,278