All Questions
Tagged with neutrons astrophysics
14
questions
4
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243
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Why the Fermi's energies of the proton, neutron and electron are related in this way in a neutron star?
I'm referring to this answer made by ProfRob about why neutrons are stable against beta decay in neutron stars.
I've partially understood the answer: when the Fermi's momentum of the electron $p_f = (...
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3
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2
answers
572
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How can there be superconducting protons and neutrons inside an incredibly hot neutron star?
It is hard enough for me to try to wrap my head around the idea of superconducting particles other than electrons (especially neutrons!), ....
Given the insanely hot temperatures inside a neutron star ...
- 4,509
1
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1
answer
18
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Pressure stabilisation of radionuclei
Looking at explanations of neutron stars, the neutrons towards the center of the star are stabilised by the enormous pressure, and so don't undergo nuclear decay. I am wondering if this is possible ...
- 131
6
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7
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As neutrons are more massive than protons, does the Sun increase its mass while fusioning elements?
Where is the mass coming from when neutrons are produced from protons in the Sun?
If a positron is made, will it possibly annihilate with an nearby electron?
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2
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Why do neutron stars have such powerful magnetic fields?
The magnetic strength of these objects is too low based on flux conservation from the original star and yet too high for a composition of mainly neutrons. Is it actually due to some quantum effect?
- 166
4
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1
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Can gravity give neutrons a longer lifespan? [duplicate]
Isolated neutrons have a lifespan of about one minute yet neutrons in a neutron star can have the lifespan of the neutron star itself and not decay into proton and electron. Is the intense gravity ...
10
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2
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818
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Neutron stars - only neutrons?
I was at a museum recently, and there was a display on neutron stars. It said that neutron stars are made only of neutrons, which honestly didn't make much sense to me - neutrons decay very quickly on ...
- 7,057
1
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1
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Why don't neutron stars transform into proton stars as a result of neutron beta decay? [duplicate]
Free neutrons, as we know them, are unstable and hence undergo a three-body decay into proton, electron and antineutrino with a mean lifetime of just under 15 minutes.
But there are astrophysical ...
- 115
5
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2
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Neutron star core understanding
From what is given here free neutrons (neutrons outside of the atomic nuclei) are unstable and decay in about 15 minutes into proton, electron and an anti-neutrino (in most cases).
Also given that ...
- 445
6
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1
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Why do neutron stars have solid crusts?
A long time ago I read that neutron stars have a solid crusts that are several orders of magnitude harder/stronger than alloys here on the Earth. So how is this possible ?
A neutron star has a ...
- 3,916
6
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2
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Free neutrons in the sun's core?
In the standard description of proton-proton fusion, the first step of the interaction proceeds through the unbound diproton $\rm^2He$:
$$
\begin{aligned}
\rm p + p &\to \rm {}^2He^*
\\
\rm ^2He^* ...
rob♦
- 91.5k
36
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4
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What stabilizes neutrons against beta decay in a neutron star?
Free neutrons are known to undergo beta decay with a half-life of slightly above 10 minutes. Binding with other nucleons stabilizes the neutrons in an atomic nucleus, but only if the fraction of ...
- 4,453
7
votes
1
answer
461
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How would nucleosynthesis be different if the neutron were stable?
If the strong nuclear force were just 2% stronger, the neutron would be a stable particle instead of having a half life of about 13 minutes. What difference would that have made to Big Bang ...
- 10.7k
7
votes
2
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What is a magnetised neutron star?
I heard the term the other day, but it seems strange to me. My understanding is that neutron stars are made up of neutrons; and neutrons (having no charge) shouldn't be magnetised.
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