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

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Nucleon-meson interaction

Suppose interaction lagrangian between neutron-proton doublet and $\pi$-mesons: $$ \tag 1 L_{\pi pn} = \bar{\Psi}\pi_{a}\tau_{a}(A\gamma_{5} + B)\Psi , \quad \Psi = \begin{pmatrix} p \\ n\end{pmatrix} ...
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What produces this 477 keV spectral line?

Question about a specific line on a gamma spectrum, here. Below is a background gamma spectrum observed by a Ge[li] detector. I've been able to identify all the lines with mostly certainty, apart ...
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General Calculations on Rutherford Scattering [on hold]

I was going through the book Fundamentals of Nanoscale Film Analysis and was trying to understand Rutherford scattering. Here is a problem from the book and it would be great if someone could let me ...
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24 views

What does the g mean after the isotope given?

I'm familiar with notation such as Sc-44m standing for the meta stable state of Sc-44. What does Sc-44g mean? There are a few examples of this notation; here's one: ...
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Gadolinium poisoning vs Holmium Poisoning [on hold]

Question here on the poisoning used around neutron spallation sources (or reactors, or any neutron source). I use poisoning in the sense of absorbing neutrons to prevent their release into the outside ...
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53 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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21 views

Gamma spectrum: Question about cross sections

If I have a gamma spectrum and I suspect that I should have an isotope, Fe-59 for example, present in the environment, I will then look here: ...
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21 views

Atomic/nuclear physics question

I've got what's probably quite a basic question here but I can't get things clear in my head. If I have a cobalt isotope like Co-56, is it possible for this to undergo Neutron capture (becoming ...
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23 views

Units in Plasma Physics

What are the units people use in plasma physics? I am having hard time converting an equation from an old paper to SI units. I saw temperature being defined in eV. I assume this is eV/kB with kB ...
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335 views

Fission of U-235 produces Cs-137 along with…?

Question about Nuclear fission in general, here. If I have the fission of U-235 and I know that one of the products is Cs-137, is there a way of figuring out the other product? Should there be ...
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53 views

How much energy is released from the splitting of a single hydrogen atom?

My question is a fairly simple one that I cant seem to find on Google: How much energy, in both technical and laymans' terms, is released from the splitting of a single hydrogen atom?
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140 views

Matter to energy conversion

Okay so I have a question, during a nuclear explosion or particle/antiparticle annihilation, matter is converted into energy. How do I determine if a from a explosion will come lets say a small ...
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What is meant by mass defect of a single neutron or a single proton?

As per my understanding The mass defect of a nucleus represents the mass of the energy binding the nucleus, and is the difference between the mass of a nucleus and the sum of the masses of the ...
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36 views

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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20 views

Should I observe single/double escape peaks for all energies above 1022 keV

I have already asked a question similar to this, but that question was specifically relating to the case of K-40. I'm going to generalize it to any case My question is to do with the field of gamma ...
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11 views

How to choose which elements to use when synthesizing an ultra-heavy element?

I've been told that synthetic ultra-heavy elements are produced by bombarding a light nucleus into a heavy one, and that several combinations are (at least in theory) possible, as long as the sum of ...
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1answer
18 views

Why do I not observe single/double escape peaks for K-40

A question on gamma spectrometry here. If I'm looking at a background gamma spectrum with a big peak at 1460KeV (approximately 180 counts) and I attribute this peak to the presence of K-40, should I ...
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1answer
26 views

Nuclear decay of V-48

I have a question on the "decay" of Vanadium-48. The reason it's in inverted commas is because I'm not sure whether decay is the right word. Basically what I'm trying to work out is whether it's ...
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Why isn't spent nuclear fuel used as a heat source? [closed]

We all know spent fuel rods taken out from a reactor core keeps generating tremendous amount of heat and needs to be kept cool by running cool water. It is also known that if cooling system fails ...
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128 views

Are there more photons than nuclei within the Sun?

Are there more photons than nuclei within the Sun? Is there a good way to estimate what the ratio would be?
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37 views

Difference between scattering amplitude and scattering lenght

I'm studying neutron scattering theory and I noticed that one usually writes the scattered wave as a spherical wave: $$\psi \sim \frac{-b} {r}e^{ikr}$$ where $b$ is known as scattering lenght. From ...
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About the flow of current

Generally it is said that current is due to the flow of electrons; how can we make this claim? I mean, generally we say the atom contains a nucleus which consists protons (positively charged ...
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1answer
19 views

Gamma Spectroscopy - Why no Intensity level for Neutron Capture?

I'm undertaking a bit of work looking at a Background Gamma Spectrum. On the spectrum, I have a clear, tall line at 834 KeV. I have a PDF file of a table of Gamma Spectra (ordered in energy) from ...
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Are there hypothetical processes which allow the existence of a fission powered star?

I know this is impractical given the rarity of heavy fissile elements in the universe (contrary to the abundance of fusion friendly elements like hydrogen), but is there any process via which a ...
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Can there be eternal stars?

the question is quite straightforward: Can there be stars that shine forever without ever collapsing nor growing? Do we know some really, really old stars? (whatever age that might be) I hope to ...
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landau distribution as a model of charge deposition in silicon detector

I am would like to know if it is any explanation why the charge collected by the detector can is model by the Landau distribution. Is it any deeper explanation instead of "it is working" ? I look ...
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66 views

Why is isospin so useful?

I'm currently reading about isospin in nuclear physics, and I know how to calculate it, and all the math, but I'm actually not sure WHY it is so useful? Can anyone come with some examples where not ...
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43 views

What actually remains after a proton-proton collision?

I have read that according to the kinetic energy of protons new particles can be created (pions, antiprotons etc) along the existing 2 protons or original protons can be tranformed into hundreds of ...
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What is the exact function of neutrons $N(Z)$?

Has the number $N(Z)$ of neutrons in a nuclei as a function of the number $Z$ of protons been fully understood? Beside being ballast which makes the nucleus heavier, what determines the number of ...
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Will ionization energy be affected by screening effect?

It would be logical to think that the more electrons are ejected from an atom, the harder it is to eject more. I just learned about photoelectric effect experiment. The book is kinda telling me the ...
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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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58 views

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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1answer
15 views

Direct vs. Compound reactions

I know there are different types of direct reactions like inelastic scattering and such. But is the main difference between direct and compound reactions that one excites (Or at least can) the whole ...
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1answer
38 views

Ground state of 113Sn from shell model

The shell model predicts that the ground state of 113Sn with 63 neutrons would have J=5/2+. But the ground state is taken to be 1/2+. What is the reason behind that? Has it got something to do with ...
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Is a turbine the same thing as a motor?

Is a turbine the same thing as a motor? We know that water, wind and nuclear power plants rotate a turbine so is this turbine like a motor? I think we can generate electricity by rotating a motor too. ...
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Aplications of algebraic topology/pure mathematics in nuclear fusion

I am planning on working on an independent research class this fall at a community college. My instructor wants to focus it around pure mathematics/topology/homotopy. I think she has done a phd in ...
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Is a Plutonium gun-type atomic bomb really “impossible”?

I caught a pretty well done 2 hour documentary on atomic bomb history yesterday on the local PBS station. In it, they go over the paths taken for design of the first bombs, including the Thin Man ...
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One Pion Exchange Potential properties for a two-nucleon system

I'm going through my Nuclear Physics book, and has come across a section called "Properties of OPEP for the two-nucleon system". It start out by considering the n-p system in a singlet spin state ...
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78 views

Lead - Lithium = Gold?

In reference to this question about transmuting lead into gold, I'm looking for a correct, though magical, way to turn lead into gold. I'm not worried if it's possible to split off a lithium nucleus ...
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Where to get the AME2012 isotope mass table?

what's the official site for getting the latest isotope mass table, i.e., AME2012? All links I have found (NIST, IAEA) point me to a site at the Chinese Academy of Sciences, but the link ...
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In the Iranian nuclear deal, how can IAEA detect nuclear activity after 24 days?

This is a question related to current events, but I want to ask about the physics, which are not explained in any news article that I can find. Ernest Moniz and John Kerry wrote an op-ed in the ...
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When does electron capture occur and when does positron emission occur?

I’ve been told that electron capture occurs when there isn’t enough energy to produce a positron by beta plus decay. Exactly why is this the case? Why does it take more energy for positron emission ...
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Can an electron in an atom have insufficient energy to achieve an energy level, or orbital, and what happens to this electron when this occurs?

If a nucleus undergoes a change in Z or Mass due decay or absorption, could this disrupt the electrons from their orbital/shell energy levels? If so, could the electrons that were previously in the ...
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154 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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23 views

Is there a directional aspect to Beta decay dependant on nucleus orientation

Does beta decay occur in certain directions relative to a nucleus orientation? Would the nucleus geometry or spin direction have an impact? This effect could may be tested if a radioactive nucleus ...
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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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Are Fe56 or Ni56 the fission products of any binary reactions?

I'm curious as to if there is some combination of a fusion and fission event simultaneously occuring that would only produce 56 nucleon number nuclides. Such that the net energy out of the fusion ...
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45 views

Binding energy and mass

I’ve been told that a greater binding energy means the nucleus is more tightly bound, and therefore that decreases the mass of the nucleus with respect to its nucleons when separated. But why does a ...
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24 views

Can a light element with excited nucleus undergo internal conversion

Internal conversion occurs when an excited nucleus ejects a low level electron from the first 2 low energy shells such as a k shell electron instead of emitting gamma when returning to ground state. ...
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Does the mass of a nucleus increase when it is excited to higher energy levels

If we consider an atomic nucleus that is excited to a higher energy level. This maybe due to absorption of gamma for example or as a result of some other decay or interaction. Would the mass of that ...