Questions tagged [nuclear-physics]
Nuclear physics is the study of the composition, behavior and interaction of atomic nuclei and their constituent parts.
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How does the second stage of a fusion bomb create and maintain the needed pressure?
My understanding of the second stage of a thermonuclear bomb is as follows:
X-rays from the first stage compress the "tamper", thereby igniting the fission sparkplug, and that the resulting ...
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How does the increased binding energy per nucleon help in stability?
I have some read answers on this forum, some books like Halliday Resnick and my course books. I have understood that binding energy is the energy we need to supply to break nucleus into individual ...
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Why do we study so much if it can't make us able to cover up our expenses? [closed]
You can use data from anywhere to answer my question. But answers should be realistic and logical.
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Why are nuclear fusion reactors difficult?
The first fission bomb was created in 1944, and the first fission reactor in 1951 (and actually productive one in 1954). This delay seems possible to explain by there being a larger amount of initial ...
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Is crossing symmetry violated in the difference between positron emission and electron capture?
As discussed in the relevant Wikipedia article, beta decay via electron capture is possible in circumstances when positron emission is not.
From a simple (and perhaps naive) point of view, the two ...
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My book says “binding energy is the energy released when a nucleus is created from another nuclei or nucleons”
According to my book “binding energy is the energy released when a nucleus is formed from nuclei or nucleons.This nuclear binding energy is derived from nuclear force “. How is the binding energy ...
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Question on probability of alpha particle scattering at certain angle after hitting a gold atom
According to this video (roughly 20 minutes in), the angle at which an alpha particle is likely to scatter after entering a certain region of a gold atom is given by
$$\sigma(\theta)=\pi\left[\frac{...
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Exchange interaction and nuclear fusion
Most texts about nuclear fusion say that the reason it is so hard to get protons to fuse is the strong Coulombic repulsion between them. However, it seems to me that at close distances, protons should ...
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Probability current: How does one write it only in terms of Imaginary terms? [closed]
How and why do we write the probability current in terms of imaginary part? What are the mathematical steps in between the steps ?
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How to explain different, seemingly inconsistent, values for the mass of the alpha particle in different books?
I’m trying to calculate the energy of an $\alpha$ particle after the decay of Ra-226 following an example in a german school book and came across different values for the mass of an $\alpha$ particle.
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How can I apply this central force projector operator?
I'm working with two neutrons bound in a 3D harmonic trap (so, living in a harmonic oscillator potential) which also interact with each other with a given potential. The states of the individual ...
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Can someone explain the equation used to calculate the nuclear diameter/radius using electron diffraction? [duplicate]
It seems as though the equation here ($d\sinθ=1.22\lambda$) is more or less the same as the equation for diffraction gratings ($d\sinθ=n\lambda$). However, in the equation for the gratings, d is the ...
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Does every element have a critical mass?
We have all heard of critical mass for radioactive materials like Uranium, Plutonium etc. but does every element theoretically have a critical mass? If not, what determines if such a phenomena is ...
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Is there a minimum mass required to create an atomic bomb? [closed]
I have heard that there is a minimum mass of fissile material required to produce an explosion. If so why would this be? Is it true North Korea found a way to overcome this?
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Nuclear level densities and neutron stars
My current PhD. project involves working with nuclear level densities (NLDs). However, I am more interested in the applications of NLDs to astrophysics. I know they are important to in calculations of ...
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Radioactive Decay of Li-8
Currently using a simulation to observe the decay of various elements. I noticed for the Li-8 there is beta decay. There are also arrows pointing from beta decay towards alpha decay and stable. Can ...
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Nuclear binding energy and natural radioactive decay
I have just started to learn about nuclear binding energy. While I believe I understand the concept well, there is one thing I do not still fully grasp.
I understand that the nuclear binding energy ...
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Books on superfluidity in nuclei
can you recommend me some books or other kind of materials to study superfluidity phenomena in atomic nuclei? I'm interested in HFB method as well.\
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Materials to Understand Energy loss of neutral charged particles such as Neutrinos?
I was reading about the energy loss of charged particles in matter and understood that the Bethe-Bloch equation governs the energy loss of charged particles interacting with matter. However I was ...
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How Does QCD Explain Nuclear Fission?
This question is brief and simple. As a layman, it is my understanding that QCD (Quantum Chromodynamics) explains the nuclear force as a "residual" force, mediated by pions (mesons), which ...
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Tensor force operator on singlet state
I am reading chapter 3 of Bertulani's Nuclear Physics in a Nutshell, and during his discussion of the tensor force operator,
$$S_{12} = 3(\vec{\sigma}_1 \cdot \hat{r})(\vec{\sigma}_2 \cdot \hat{r}) - \...
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Anisotropic radiation from excited nuclear states
I come from particle physics background, but I want to understand something related to nuclear physics. I don't have any training in nuclear physics, but please feel free to share any equations.
If ...
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Why are nuclei with large numbers of neutrons only stable with correspondingly large numbers of protons? [duplicate]
Large numbers of protons need to be separated by neutrons, otherwise they repel....
But why do nuclei with large of numbers of neutrons only remain stable with a relatively, correspondingly large ...
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Why did Yukawa theorize a neutral pion? Was it necessary or a guess?
At the time, neutrons had just been discovered, but were only needed to explain the extra mass inside nuclei...
We now know that the strong force isn't strong enough to hold positive protons together ...
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$Q$-Factor for Beta Decay
I am struggling to understand the $Q$-factor for the $\beta^-$- decay process. My understanding of the $Q$-factor is that it's the difference in binding energies before and after the chemical reaction....
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Are all mass eigenstates also spin eigenstates?
Is there a rigorous way to show that a mass eigenstate of a particle must also be an eigenstate of the total spin operator? If this wasn't true, you could imagine that a composite particle in a mass ...
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How did Enrico Fermi compute when the Chicago Pile-1 nuclear reactor would become critical?
I'm trying to understand the first nuclear reactor, the Chicago Pile-1, specifically the math Fermi did to figure out when the reactor would go critical. There's a nice report available from Fermi, ...
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In the early universe (quark-gluon plasma), was there such a thing as a gluon wave like an EM wave and gravitational wave?
I have read this question:
Participating in strong interactions between the quarks, they are "trapped" within a very tiny region of spacetime that we call "hadron". We don't see ...
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Statistics error limit on a fitting
We are trying to analyze gamma-ray spectra that come from a neutron scattering in the soil sample. Our hope is to find the final error in the fitting parameters of the peak, which should look like a ...
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Binding energy per nucleon vs binding energy
What is the physical difference between binding energy and binding energy per nucleon? Which one is the energy required to split nucleus into individual nucleons?
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How is the branching ratio defined for nuclear reactions?
The Wikipedia page for candidate nuclear reactions for terrestrial fusion power notes that the D + D and He-3 + T reactions can proceed through either of two alternative routes; for example:
(2i) D ...
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How does CT imaging deal with the thickness of materials?
In the medical CT imaging field, image of an inspected object is obtained through xray projection. xray is attenuated by the inspected object through the formula $I=I_0e^{-\mu t}$. The projection $p$ ...
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What would the nucleus of a water planet be like?
If we have a planet made out of water, would it be all solid? What about the nucleus? Would it depend on the size of the planet?
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Drawing energy level digram of excited states of any nuclei using proton scattering
I am studying Nuclear Physics and I do not completely understand how to draw the energy level diagram for the excited states of a nuclei. I have been given a graph which provides information about the ...
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Do forces get affected by relativity?
Do forces change their behavior due to the relativity?
For example if a charged particle deflects through an electric field, would the pattern and amount of deflection differ in speeds near speed of ...
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Can the nucleus be ionized?
Traditionally, the word ionization is conceptualized as the removal of electrons from an atom to leave a net charge on that atom. This is generally achieved through the bombardment of high energy ...
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Are there any specifications required for the computer which would be connected to Computer Automated Measurement and Control (CAMAC)?
I wanna buy a computer to use with Computer Automated Measurement and Control (CAMAC).
Are there any specifications required for the computer which would be connected to CAMAC?
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Why do we use nuclide mass in nuclear reactions instead of nucleus mass?
Why do we use nuclide mass in nuclear reactions instead of nucleus mass in the calculation?
When trying to find the energy released in a nuclear reaction, the mass difference is calculated and put ...
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Does producing a heavy nucleus release more energy than producing two lighter nuclei with the same number of protons and neutrons?
Does producing a heavy nucleus release more energy than producing two lighter nuclei with the same number of protons and neutrons? If this holds true what is the reason behind this?
Say we have 20 ...
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If there wasn't a weak nuclear force, what would be the heaviest stable theoretically stable isotope with equal protons and neutrons?
If there was no weak nuclear force, what would be the heaviest stable theoretically stable isotope with equal protons and Neutrons? For our universe the heaviest such isotope is calcium 40, but most ...
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Is the energy of matter (via $E=mc^2$) actually available to do work?
If energy is functionally defined as the capacity to do work, then in what sense does mass offer a lot of energy (via $E=mc^2$). Most people responses I've seen to similar questions state “there’s a ...
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Beta-decay of a Tritium [closed]
Calculate the probability of a Tritium beta decay into ground state of a Helium ion with perturbation theory.
What should I start with? I lack any ideas.
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Doppler broadening and Voigt profile
The shape of an isolated neutron resonance at incident neutron energy, $E_{R}$, can to first-order be represented by the single-level Breit-Wigner (SLBW) formalism, which is equivalent to a Lorentzian ...
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Could somebody explain alpha channeling in tokamaks?
Could somebody explain alpha channeling in Tokamaks and mirror machines? Energetic alpha particles (in the center of the torus or mirror device) born in fusion reactions, interact with a wave and ...
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What determines the path in radioactive decay series?
How an element decays can be plotted in a diagram like this:
source: https://chem.libretexts.org/Courses/City_College_of_San_Francisco/Chemistry_101B/10%3A_Nuclear_Chemistry/10.3%3A_Radioactive_Decay
...
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How to treat the thickness of materials in dual energy computed tomography (CT)? [duplicate]
In computed tomography (CT) imaging, the dual energy CT extracts the mass density of two materials based on linear mass attenuation. With two measurements at two different energy, the dual CT can ...
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It is possible to combine two heavy elements into one?
Is it possible to combine say two uranium atoms into very heavy new element? Periodic table ends around 115 today, but can it go forever technically?
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How can the binding energy per nucleon graph be useful if you can't compare "all" products with "all" reactants?
How can the binding energy per nucleon (BEN) graph be useful if one can't compare "all" products with "all" reactants?
Take the fission process of Uranium to Thorium:
$${}^{238}U \...
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Mass per nucleon graph
I am a high school student and am struggling with understanding the significance of the mass per nucleon graph.
What does this graph show with regard to nuclear reactions? (y-axis: M/A, x-axis:A) I ...
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Construction of the wave function of $D$ mesons
The $D^{\ast+}$ meson can decay as $D^0+\pi^+$ or as $D^++\pi^0$. It is a vector meson, therefore having $J^P=1^-$. Furthermore, $D^+$ is made of $c\overline d$ and $D^0$ of $c\overline u$. The ...
