Questions tagged [neutrons]
The neutron is a subatomic particle, with no net electric charge and a mass slightly larger than that of a proton. It is a fermion of spin $\frac 1 2$; a hadron, that is it interacts strongly; and a nucleon, that is a crucial component of atomic nuclei.
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Why is the (free) neutron lifetime so long?
A neutron outside the nucleus lives for about 15 minutes and decays mainly through weak decays (beta decay). Many other weakly decaying particles decay with lifetimes between $10^{-10}$ and $10^{-12}$ ...
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What makes the number of neutrons the number of proton similar?
In basic chemistry, we are taught that an atom has roughly the same number of neutrons and number of protons, this doesn't seems to hold for larger atoms, but it is always roughly proportional (i.e. ...
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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 ...
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How come neutrons in a nucleus don't decay?
I know outside a nucleus, neutrons are unstable and they have half life of about 15 minutes. But when they are together with protons inside the nucleus, they are stable. How does that happen?
I got ...
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Adding many more neutrons to a nucleus decreases stability?
If you take any large nucleus and add protons to it, the electrostatic repulsion between them will make the nucleus more unstable, because the electrostatic force between them is more repulsive at a ...
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Why do neutrons repel each other?
I can understand why 2 protons will repel each other, because they're both positive. But there isn't a neutral charge is there? So why do neutrons repel? (Do they, or have I been misinformed?)
The ...
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What's with the very slightly larger mass of the neutron compared to the proton?
Neutron mass: 1.008664 u
Proton mass: 1.007276 u
Why the discrepancy?
On a related note, how does one go about measuring the mass of a neutron or proton, anyway?
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Why is the density of the Fermi gas in a neutron star not changing the potential depth caused by the strong nuclear interaction?
In some textbooks, the neutron star is explained as a degenerate Fermi gas. To calculate the degenerate pressure of the neutron fermi gas the average Energy of a neutron, U is calculated when the ...
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Why does the neutron have an electric dipole moment?
As I understand it, the neutron is believed to have an electric dipole moment (the so-called "$nEDM$"), the precise value of which hasn't been pinned down, although we've been able to place ...
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Anti-Particle of Neutron
The anti-particle corresponding to a proton or an electron is a particle with an equal mass, but an opposite charge. So what is the anti-particle corresponding to a neutron (which does not possess a ...
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Stable Nuclei - Deviation from equal protons and neutrons
While studying the semi-empirical mass formula for nuclei, I came across an "asymmetry term" whose function, as far as I understand, is to build in the fact that nuclei "prefer" to have equal numbers ...
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How is it possible to accelerate a neutron?
It is possible to accelerate a charged particle in an electric field, how is it possible to accelerate a neutron? How can we control its velocity?
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How would neutron matter appear to the naked eye?
Neutron matter is matter comprised entirely of neutrons, as it exists in neutron stars.
Most optical phenomena encountered in everyday life, such as light reflection and spectral absorption (i.e. ...
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What do we know about the interactions between the protons and neutrons in a nucleus?
In a nucleus, the strong nuclear force causes interactions between protons and protons, between neutrons and neutrons, and between protons and neutrons. What do we know about this interaction?
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Charge structure of the neutron
David Griffiths’ book on elementary particles says that the neutron is positive at the center and edges, negative in between. (Introduction to Elementary Particles, Wiley, 1987, p. 21).
But Wikipedia ...
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