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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Improved estimate of density of free neutrons in solar core
In an answer to this question:
Free neutrons in the sun's core?
I made a very rough attempt to estimate the density of free neutrons in the solar core. There is some non-zero rate for production ...
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Do electrons define the element? [closed]
In a nuclear reaction, protons and neutrons are exchanged and the resulting elements have a number of different protons and neutrons that uniquely define the element that we are studying.
However, can ...
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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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Potential yields of Np-237 using a synchotron
U238 releases a neutron when it is exposed to photons of around 11 MeV, and the resulting U237 promptly decays into the fissile Np237.
In such a situation, what equations can I use to relate the ...
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$\beta^{+}$ and $\beta^{-}$ decay processes
We know that electron cannot exist inside the nucleus for various reasons like its energy, angular momentum violation and etc. But these $\beta^{+}$ and $\beta^{-}$ processes occurs inside the nuclei ...
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Has Anti-beta decay been observed?
I am looking for references or resources regarding the transition of an anti-neutron through weak decay, into an anti-proton, positron, and electron-neutrino.
Have such studies been conducted or ...
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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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Refractive index of EM waves travelling though a gas of neutral particles
From what I have read and seen online. The explanation of why there is a net reduction in the speed of EM waves through a medium is due to the interference with the oscillating EM fields produced by ...
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In a fission reaction mass is converted to energy my students are asking where the mass is taken from - do the nucleons have less mass afterwards? [duplicate]
I am teaching year 11 Physics for the first time. In a fission reaction mass is converted to energy my students are asking where the mass is taken from - do the nucleons have less mass afterwards?
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Spallation neutron sources + wakefield particle accelerator + U-238 for generation of Pu-239 [closed]
I am looking to combine the principles of spallation neutron sources, wakefield particle accelerators, and neutron absorption to enable anybody to create large amounts of plutonium using relatively ...
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Can Neutron Activation Analysis differ isotopes?
I know to carry out an NAA analysis, the specimen is placed into a suitable irradiation facility and bombarded with neutrons. This creates artificial radioisotopes of the elements present. Following ...
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Is it possible to collide two neutrons? [closed]
If it is possible to collide two neutrons, how is it so? What particle accelerator or pre-collision processes are necessary and what results can be expected? If the products of neutron-neutron ...
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Is an electron more stable than a proton/neutron?
Is an electron more stable than a proton/neutron under extreme temperature/pressure conditions, like several 100 millions K?
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Stacking of magnetic moments in a polarised neutron beam
Neutrons are particles that have a half spin and a magnetic moment. if you polarise a beam of neutrons so that they all align with spin +1/2 will the combined neutron beam have an overall magnetic ...
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How electron, proton and neutron have mass numbers
As far as I know, the mass number of an atom means the amount of protons and neutrons it has. For example, the mass number of Sodium (Na) is 23 since it has 11 protons and 12 neutrons. Then how ...
