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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What is the cause of the minor mass difference between the proton and the neutron?
As known, the proton is from two up and a single down quark, while the neutron is from a single up and two down quarks. The down quark is a little bit more massive and the up, and so the neutron is ...
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Is it a coincidence that Big Bang nucleosynthesis lasted about one free neutron half-life?
The free neutron half-life is about 10 minutes. Big Bang nucleosynthesis, which mostly involves protons and neutrons interacting, lasted about 20 minutes.
Question: Is it a coincidence that these ...
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Why is the neutron cross section of hydrogen larger than that of deuterium?
The scattering neutron cross section of hydrogen is about $20$ b, five times larger than that of deuterium. The capture cross section of hydrogen is around 3 orders of magnitude higher than that of ...
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Why does the neutron have spin 1/2 and not 3/2?
The neutron is thought to consist of three tightly bound quarks, each with spin 1/2. Simple addition of angular momentum would tell us that the resulting system (neutron) could have either spin 1/2 or ...
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Intensity of inelastic neutron scattering: analitycal expressions
I am currently working with experimental results of magnon spectrum (in antiferromagnet with many atoms per unit cell), which was obtained by inelastic neutron scattering method, but some spectral ...
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On the construction of atomic kernels
Can anybody point me to an English translation of Heisenberg’s three part paper Über den Bau der Atomkerne?
Failing that, can you point me to a non-paywalled German version of part III? I have parts ...
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Where can I find accurate visual representations of atomic nucleus nucleons wave probability functions like I see for electron atomic orbitals?
Note the Wikipedia article for 'Atomic nucleus' was awkward here because first they depict the old concept with protons and neutrons as a bunch of spheres touching each other and in the sub-text ...
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How can I visualize the oxygen nuclear charge density?
Oxygen has 8 protons and 8 neutrons.
Based on the nuclear shell model, protons should pair with anti-parallel protons to create singlet spin states,
and neutrons should similarly pair with anti-...
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Magnetic moments of nucleons
I was comparing my notes of the nuclear physics class (undergraduate level) on magnetic moments of nucleons with the Krane's explanation.
In my notes I wrote that there are two types of magnetic ...
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Is it possible to produce a focused, high-intensity neutron beam?
Since neutrons are uncharged, exceptionally hard to control, my understanding is that particle accelerators can never directly produce a beam of neutrons. Instead, they need to accelerate some charged ...
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How does QED describe the electromagnetic scattering between two neutral fermions?
Fermions with no electric charge may carry magnetic moments e.g., the neutron. Since particles with magnetic magnetic moments interact, they're expected to scatter off each other electromagnetically. ...
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How is the Neutron capture cross section of Xenon-135 so high?
Xenon-135 has a Neutron capture cross section of 2-3 million barns, this is equivalent in area to a disk with a radius of 8-10pm. The cross sectional area of a Uranium nucleus is roughly 1 barn. The ...
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Does an accelerating neutron produce electromagnetic waves?
I believe both protons and electrons do produce e/m radiation if accelerated, but what about a neutron which is made up of, or at least decays to, an electron and a proton?
If accelerating a neutron ...
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How are we sure that the measured proton spin puzzle will be also observed similarly in the neutron thus a neutron spin puzzle?
The EMC experiment in 1988 using muons' deep inelastic scattering, has reported that the contribution of the valence quarks triplet (i.e. up-up-down) in the proton was measured to contribute as little ...
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Why do Xe-135 and Zr-88 have a surprisingly large thermal neutron capture cross-section?
Why do Xe-135 and Zr-88 have surprisingly large thermal neutron capture cross-sections?
The probability that a nucleus will absorb a neutron—the neutron capture cross-section—is important to many ...
