Nuclear physics is the study of the composition, behavior and interaction of atomic nuclei and their constituent parts.

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Electrical neutrality of atoms

How is it that atoms with equal numbers of protons and electrons are described as "electrically neutral" when the proton is 1,800 times more massive than the electron?
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gamma ray lasers?

Is it really possible in the foreseeable future to create a gamma ray laser? I've read these two articles on Wikipedia: the Hafnium controversy Induced gamma emission It sounds pretty amazing, ...
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What determines the distribution of the energy between the beta-particle and the neutrino in beta decay?

When beta-decay occurs an electron or a positron is emitted along a neutrino or an antineutrino. The energy spectrum of the beta particles is continuous because, as I read, the energy is shared ...
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The synthesis of $^{254}\text{No}$

How is $^{254}\text{No}$ synthesised? Could you explain the reaction where it is preceded by $^{208}\text{Pb}(^{48}\text{Ca}, 2\text{n})$? References to articles are well enough—I was somehow unable ...
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What's the slowest nuclear decay rate that's been measurably linked with a narrow energy linewidth?

As was explained in the question What is the relation between the half-time and the line-width of a radioactive nucleus?, the half-life $\tau$ of an unstable nucleus is related to the linewidth $\...
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Why do nucleons feel a repulsive force when less than 1 fm?

My Modern Physics textbook by Taylor states that when nucleons are less than 1 fm apart, there is a strong repulsive force between them. I am fairly certain that it is not the Pauli Exclusion ...
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What is the shielding in nuclear reactors mainly against?

I have a little knowledge about ionizing radiation and I have been confused over why nuclear reactors need these massive shields. So, if I am not mistaken, Alpha and Beta radiation are not that ...
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259 views

Shell model of an odd-odd nucleus: $^6$Li

Lithium-6 isotope has an approximate magnetic momentum of $0.88\ \mu_N$ in its fundamental nuclear state. I'm trying to find its angular momentum and parity. I found in a standard table: $I=1^+$ and ...
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Pressures Necessary for Carbon Detonation

Carbon detonation is a characteristic event of Type 1a Supernova (EDIT: where an accreting white dwarf near the Chandrashankar limit of 1.4 solar masses explodes), an extremely important standard ...
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Does the Breit Wigner formula apply to intermediate virtual particles?

Breit Wigner Formula describes the cross section for interactions that proceed dominantly via a intermediate particle (O*) A+B → O* → C + D: $$σ = \frac{2\Pi}{k^{2}}\frac{Γ_{i}Γ_{f}}{(E-E_{o})^{2} + (...
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Fission producing Cs-137

This is I suppose quite a precise question about Nuclear fission. What produces, aside from U-235, via a fission process, Cs-137? Does any isotope of Actinium, for example, undergo a fission process ...
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Nuclear physics problem, Why do we use high weight atomic elements?

So as far as I know, nuclear fission uses high weight atomic elements to manufacture power. If the risk of runaway reactions are a major reason for not expanding this technology, why don't we use ...
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Is there an equation for the residual strong nuclear force?

First of all, note the qualifier "residual". The present question is not the same as that asked, and answered, in the StackExchange question "Is there an equation for the strong nuclear force?" which ...
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Binding energy in fission

In nuclear fission the total rest mass of the products is less than the mass of the original nucleus. But on the other hand, the binding energy of the products is higher. Doesn't the decrease of the ...
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Would a matter-antimatter explosion cause fallout?

I know matter and antimatter annihilation release a lot of gamma rays which are considered ionizing radiation if I am not mistaken. But what if the explosion happened on the surface of the earth, ...
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Hamiltonian Nuclear collective model

Let $\mathscr{I}_3$ and $\mathscr{I}$ are the moments of inertia for rotations about symmetry axis 3 and about an axis perpendicular to it , and I is the angular momentum operator with components $I_1,...
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Would it be possible to detect nuclear explosion on exoplanet?

How strong would have to be nuclear explosion on exo-planet that orbits some other star for it to be detectable outside of that system. Or it would be impossible due to amount of radiation coming from ...
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659 views

Was the early Earth radioactive?

I've been reading of the (surprising) fact we are uncertain on whether there is nuclear fission in the center of the Earth or not (yet we know so much detail on structures at the other end of the ...
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Which is larger, all known, bound nuclear energy levels, or known, bound atomic energy levels?

Both the atomic nucleus and the electrons are (complex) quantum systems and have large numbers of energy levels and transitions, and a basic shell model is usually part of introductory atomic physics ...
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Why do nuclear multipole moments of charge density vary with isotopes?

Why do some isotopes have different quadrupole/octupole moments, when these moments of charge density should be independent of mass?
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Does the rest mass energy include the potential energy of the particle?

The potential energy (as far as I have studied - that is, mainly classical physics) depends on the reference level, since its absolute value cannot be calculated. It can therefore be negative as well. ...
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Relationship between time, separation and neutron transfer probability?

As an ansatz, suppose we know that when a smaller nucleus is incident upon a larger one with 1 MeV of kinetic energy, there is a nontrivial probability that a neutron will tunnel from the smaller to ...
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What is the minimum density required for nuclear fission?

This is a followup to a prior question I asked about gaseous nuclear fission. What is the lowest nuclear fuel density required to initiate fission? This is critical for a gas core reactor with a ...
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Ratio of Size of Atom to Size of Nucleus

I have the following problem: In nuclei, nucleons exists in nuclear energy levels and in atoms, electrons exist in atomic energy levels. The order of magnitude of nuclear energy is 1MeV whereas ...
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Explanation of energy levels in molecules, atoms, nuclei and their relationship

Why are the energy levels of molecules, the atoms that form them and the nuclei inside the atoms considered separately? Or phrased in a different way- what is it that makes their energy levels so ...
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Why don't neutrons cluster on their own?

"The answer lies in their one part in a thousand extra mass. Adding neutrons costs a little in mass, and in Einstein $E=mc^2$ implies that mass equates to energy. So it costs energy to add neutrons(...
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Form factor for Proton

To find the charge distribution of proton , we study electron proton scattering and compute the form factor to find the cross section. The form factor comes out to be Fourier transform of charge ...
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Binding energies of Be

Just a quick question. How does Beryllium 8 decay into 2 alpha particles? Beryllium 8 has a binding energy of 56.499508 Mev An alpha particle has a binding energy of 28.3 so two of these would have ...
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Why should odd-ordered electric multipole moments vanish?

In the multipole expansion of the radiation field of a nuclear, it is considered that the odd-ordered poles (like electric octupole) must vanish in order to conserve parity. But there exist many ...
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In what environments can a dipolariton form?

In what environments can a dipolariton form? The article in Science in which it is introduced discusses it in the context of an optical cavity in a semiconductor. Can this quasiparticle occur ...
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What combination of stable GE isotopes make up the germanium in a Ge(Li) spectrometer

I work with a Ge(Li) gamma spectrometer. I'm trying to work out the different populations of stable Germanium isotopes in it. I'm trying to model the unrealistic scenario where none of these isotopes ...
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Is it really possible to create some mass only from equivalent energy? [duplicate]

From Special theory of relativity we know that $E=m_0 c^2$, which says about mass energy equivalency. But my question : **Is there any real experiment where some mass is created purely from energy? **...
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Isoscalar and isovector terms in optical model potential

How does one obtain the isoscalar and isovector terms of the nucleus-nucleus interaction potential and what do they signify?
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Is a nuclear bomb in some sense a bullet travelling at the speed of light, but along time rather than along space?

Apologies if this is a silly or perhaps obvious question, but $E=mc^2$ just looks so much like classical kinetic energy (except for the factor of 2). So I'm thinking of the to-be-fissioned-away ...