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Assuming the water can't cool, then after about 30 minutes, all the neutrons have decayed to protons and electrons, the resultant antineutrinos escape, but an average of around 0.5 MeV per decay will get thermalised in the water (the range of the electrons will be of order 1cm). As Floris points out, it takes 15.8kJ to heat a gallon of water by 1K, so this ...


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One really, really energetic one might do it. But it would need to be very close to the speed of light, and I'm not sure you could capture its energy to boil the water. Assuming you want to convert the mass of a non-relativistic neutron to energy, it's about 940 MeV per neutron. Boiling a gallon of water (starting at room temperature, 20°C) requires raising ...


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One thing to note is that you are not using the primitive cell, which is obtained by taking the lattice vectors joining your A atom to the A atom diagonally down and to the right and from the original A atom diagonally up and to the right, such that the A atoms sit at the lattice points, and the B atom sits in the space between.


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Nuclei belong to the quantum mechanical framework, the underlying network of all natural forces. They are composed out of protons and neutrons . Protons and neutrons are composed out of 3 quarks each , between quarks , the strong force described by quantum chromodynamics generates the "bag" where the quarks are tightly bound and exist in a sea of gluons ( ...


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My intuitive thinking is that the four nucleons form could be modeled as a tetrahedron--with each nucleon at a vertex and pressed tightly against each neighbor. If you place each of the four particles at the vertices, then each has one like-particle neighbor, and two unlike-particle neighbors. Such a composite particle is known as an alpha particle--and is ...


1

You can only have an inelastic collision between two bodies if one or both of the bodies have some internal degrees of freedom that can absorb energy. For example if you have a rigid sphere then the only type of energy it can possess is kinetic energy. If we collide two rigid spheres then conservation of energy means the sum of the kinetic energies before ...


0

Beta decay occurs, approximately, in nuclei where the Fermi energy of one species of nucleon is higher than the first unoccupied orbital for the other species. In these nuclei energy can be liberated by turning one type of nucleon into another --- the new nucleon moves into the available, lower-energy orbital. By definition, a nucleus with neutron excess ...


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We think we understand fairly well how the universe makes neutrons: initially by baryogenesis and nucleosynthesis (see https://en.wikipedia.org/wiki/Big_Bang_nucleosynthesis#Neutron.E2.80.93proton_ratio and https://en.wikipedia.org/wiki/Nucleosynthesis) and later, as soon as the stars start to shine mostly by fusion (see ...


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The approximation you are referring to is the scattering length. Neutron scattering lengths are tabulated in a few places, such as at NIST; more elaborate cross-section data is tabulated at the National Nuclear Data Center. Note that the cross section depends on the neutron energy. Most tabulated cross sections are for "thermal" neutrons with kinetic ...



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