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

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Where does the “borrowed energy” come from in Alpha decay?

I was also thinking about the uncertainty principle in regards with energy & time. The question of something like: Alpha tunneling out of the nucleus is where this can be invoked, but having an ...
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67 views

References for nuclear masses, mass deficits, decay rates and modes

Where can I find the base data for computing the energy release of nuclear decays and the spectra of the decay products? My immediate need is to find the energy release by the beta decay of Thorium ...
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270 views

Relativistic Mass including exponential decay

So from what I gather, relativistic mass = $m_0\gamma$ where $\gamma$ is the lorentz factor. So if i have a mass that is .5 at rest then it is safe to say that the relativistic mass will be 1 if it ...
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Combining chemical elements

Prof Brian Cox mentioned on Wonders of the Universe when discussing chemical elements that Carbon 12 consists of 6 protons and 6 neutrons, he also mentioned that Helium consists of 2 protons and 2 ...
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283 views

Why does Fukushima pressure rise? [duplicate]

Possible Duplicate: Why didn't the control rods in Fukushima shut down the reactor? They say that pressure rises and that this can be dangerous. But why does this happen if the reactor is ...
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16 views

How to calculate exposure of beta and alpha decay

Is there a way to calculate exposure in roentgen from activity of from q-values? I currently have the activity of a beta decay in mCi over a certain amount of time and the total amount of energy, ...
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32 views

Why are parallel spins energetically favorable for nucleons? [duplicate]

For deuterium, both the proton and neutron preferentially occupy $1s_{1/2}$ orbitals which have orbital angular momentum $l=0$ and spin $s=1/2$. By coupling their orbital and spin angular momenta for ...
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51 views

Why is Helium an anomaly on the binding energy curve?

So I'm failing to understand why helium is anomalous on the binding energy curve. I know it includes concepts such as pairing, shell correction, and the liquid drop model. However, these were simply ...
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1answer
37 views

How is the amount of radiation calculated from a decay?

Lets say you have some unstable isotope which decays via beta decay. For example, lets say you want to calculate the amount of beta radiation that is emitted from the decay of $^{87}\textrm{Kr}\to ^{...
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46 views

Derivation of Critical Mass of U-235

I am having trouble following an explanation of the critical mass of U-235 from my book (for high school physics). First off, every chain reaction of U-235 releases on average $\nu = 2.42$ neutrons. ...
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33 views

Model for obtaining the magnetic moment of a neutron [closed]

The anomalous magnetic moment of a neutron ($g_s=-3.83$) could be considered as a fixed proton ($g_s=5.58$) with an orbiting $\pi⁻$ meson in an $l=1$ state. a) What is the magnetic dipole moment of ...
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37 views

Determining thickness of Aluminium foil with alpha particles

So I'm trying to derive an equation to determine the thickness of a thin aluminium foil using Bragg Kleeman rule. I've so far got that the range of the alpha particles in aluminium is $R(Al)=R(air)\...
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41 views

Why build so big sarcophagus in Chernobyl instead another alternative? [closed]

As title, why build so big sarcophagus in Chernobyl? The new sarcophagus is really tall, large and expensive and it should cover the old one. But there is already a sarcophagus build over another ...
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28 views

Can there be a two-neutron bound state? [duplicate]

Is is possible for two neutrons to be in a bound state, assuming that they only interact gravitationally?
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1answer
43 views

Does nuclear fusion of light nuclei occur in fire or boiling water?

At the temperature range of ordinary fire or maybe even ordinary boiling water, is the Coulomb potential between light atomic nuclei occasionally overcome to give way to fusion? Basically, how are ...
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66 views

Why positron emission is unlikely to occur for nuclei with an excess of neutrons?

Is it because a neutron decays into a proton and electron rather than a positron. Which type of nucleus emits positron and which emits electrons . Is it something to do with beta plus and beta minus ...
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34 views

Timescale of nuclear interaction

Can the timescales of nuclear interaction processes, like inelastic scattering or transfer reactions be found out?
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18 views

Why does the alpha particle not excite the isovector transitions in nuclei?

The $\alpha$ particle is a very commonly used projectile for studying inelastic scattering. It has T=0 ans S=0. But it only excites the isoscalar vibration modes in target nuclei, and not isovector ...
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20 views

Using ion radiation to make electricity? [duplicate]

Is it possible to capture the ion radiation from a nuclear source and make electricity from it? I always thought it was possible, but never looked into it? Is this what a beta voltaic battery does?
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31 views

Cloud chamber and observations [closed]

What are the best ways to use a cloud chamber to study particles. What would you gain from observations done in a cloud chamber.
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Random Phase approximation (RPA) in nuclear physics [closed]

What does RPA mean? What makes it significant to be used to determine nuclear transition strengths and how?
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25 views

To which extent is the treatment of nuclear multipole radiation by the means of a classical electromagnetic field valid?

In the treatment of nuclear multipole radiation, for example in the context of nuclear gamma decay, it is standard, at least at the elementary level, to formalize the electromagnetic radiation as a ...
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13 views

How can I read the rotational bands of nuclei from nuclear data sheets?

Recently I have been reading about collective excitations in nuclei and how in deformed nuclei rotational bands are formed due to an electric quadrupole moment. Given this I was wondering how I can ...
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34 views

Sustained nuclear criticality in liquid vortex

In 1958, chemical operator Cecil Kelley was killed by a nuclear excursion in a mixing tank. A tank intended to reprocess trace amounts of dissolved plutonium-239 accidentally had dramatically more ...
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72 views

Cesium-137 From Fukushima Meltdown

I've been reading up on the Fukushima nuclear meltdown and its effects it had on the environment. The iodine-131 initially released from the incident decayed after 8 days, but other isotopes such as ...
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Is Blatt-Weisskopf's treatment of nuclear forces still relevant today?

As in the title, is the treatment of nuclear forces by Blatt and Weisskopf, as in Chapter III of "Theoretical Nuclear Physics", still relevant today, especially with regard to the role of exchange ...
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1answer
51 views

Are the leptons in $\beta^-$ decay already present in the nucleus in some form?

In beta minus decay, beta-minus particle and anti-neutrino are ejected, leaving behind daughter nucleus. $\beta^-$ and anti-neutrino both are leptons. Were the leptons already present in the ...
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Condition for the perfect triaxial body [closed]

Why do a nucleus (body) having asymmetry parameter gamma=30 degree called as perfect triaxial nucleus?
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What happens to covalent bonds after the nuclear transmutation of an atom in a molecule?

What happens when we have a decaying atom in a molecule, which has covalent bonds with other atoms? I assume some of the bonds will cease to exists, but I did not manage to find any rule about which ...
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37 views

Quark axial-vector current in nucleion

In almost all direct detection articles (see for example Jungman, G., Kamionkowski, M. & Griest, K., 1996. Supersymmetric dark matter) I found the following parametrization for the matrix element ...
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37 views

Which force accelerates product particles in nuclear reactions?

In nuclear reactions, the difference between the binding energy of the reactants and that of the products is converted to the thermal energy of the products. Is the Coulomb force that actually gives ...
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23 views

Diffusion of magnetization (NMR)

In the context of MRI I'm trying to understand the mechanisms of magnetization diffusion. Consider a sample that is magnetized by an external magnetic field. We have displacement of magnetic moment ...
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61 views

Positive/negative octupole moment of nuclei?

Does octupole moment of nuclear charge distribution show any positive/negative character, like the quadrupole moment does? Quadrupole moment has prolate and oblate types, but what about ...
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18 views

Modelling populations of GE isotopes

I asked a question similar to this here: What combination of stable GE isotopes make up the germanium in a Ge(Li) spectrometer And got some very good answers. This question is instead based on the ...
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41 views

Meaning of 'nuclear surface vibrations'?

Would like to know the meaning of nuclear surface vibrations as mentioned by Bohr in his paper titled 'The coupling of nuclear surface vibrations to the motion of individual nucleons'. The paper talks ...
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Coincidence summing in gamma spectrum

Question on coincidence summing here. I've been reading about the coincidence summing effect when a radionuclide has two energy levels that decay to another state in rapid succession. There is also ...
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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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38 views

Why asymmetric fission product is so enhanced?

The thermal fission yield of usual Pu, U mix https://en.wikipedia.org/wiki/Nuclear_fission#/media/File:ThermalFissionYield.svg is tuned in a way that practically ignores symmetric yield. But if we ...
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79 views

Estimation of the age of Earth

By calculating the ratio of U-238 to Pb - 209 the age of the earth can be estimated. Is it not a possibility that non radioactive lead already there formed during the birth of earth it self alter the ...
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23 views

Fermi's yield estimation of the Trinity Test [duplicate]

In Enrico Fermi's eyewitness account of the Trinity nuclear test in 1945, he gives a brief description of a method that he used to estimate the blast energy of the test: About 40 seconds after the ...
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254 views

Pentaquark spin prediction

Is there a straightforward way to see what the spin of the recently-discovered pentaquark states should be, from the representation theory of $SU(3)\times SU(2)\subset SU(6)$? I can see that from the ...
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28 views

Effect of nucleus geometry and states on the Coulomb barrier and the electric potential well surrounding the nucleus

In some models of the nucleus it has a geometric aspect due to the combination and alignments of the charges, magnetic moments and spins of the protons and neutrons it contains. Even in models that ...
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Distribution of fragments in fission reactions

What decides the mass and charge distribution of fission fragments? are these factors decided at or before the saddle point? and how? Why does the valley in the distribution function become shallow on ...
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55 views

Multipole expansion of Woods-Saxon potential?

When can a distribution be expanded in multipoles? What is the basic requirement? Can it be done for a potential like the Woods-Saxon form?
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59 views

Nuclear shapes and deformation

How do the experimentally measured multipole moments (static or transition) give information about the deformed nuclear shape? Since deformation is not directly observable, the only information we get ...
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Klein-Nishina for estimating X-ray cross section

I'm looking at interaction probability for X-rays with water and DNA, and recently have starting reading up on the Klein-Nishina identities for differential cross section. When integrated over all ...
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3answers
228 views

Binding Energy of an atom

I would like to know if there is any difference between the binding energy of a nucleus and the binding energy of an atom and what exactly do we mean when we say Binding energy per nucleon.. Edit to ...
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194 views

What is the difference between mass defect and mass deficit?

Is there any difference between the mass defect and the mass deficit? I have read that the mass defect of a nuclide is never negative and have also been told that the mass defect is the same as the ...
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59 views

What happens to the nucleus energy when it decays?

When an atom decays into another atom, what happens to the potential energy of the nucleus ? I think it will get more negative because, in general, through fission and fusion an atom tries to get a ...
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274 views

Mirror nuclei: accounting for the difference in mass between nuclei

I was wondering if anyone here could guide me in the right direction with respect to the following problem: Two nuclei are considered mirror nuclei if interchanging the neutrons and protons turns ...