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

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301 views

Does the population of higher level s-shells affect the decay rate of alpha emitters?

Consider a nuclide like $\mathrm{^{232}Th}$, which has a half-life of 1.4e10 years and which decays by $\alpha$ decay to $\mathrm{^{228}Ra}$. Alpha decay is a quantum mechanical tunneling process in ...
1
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1answer
137 views

What happens to mass during beta decay?

Sorry for being ignorant, but I'm in high school and our chemistry teacher barely went over beta decay. I decided to do some research and learned that in β+ decay, positrons are emitted from protons ...
1
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1answer
146 views

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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4answers
119 views

Why can't a nuclear reactor be used as a rocket motor?

Nuclear fission, and potentially fusion, reactors generate vast amounts of energy, primarily as heat. What stops us from harnessing that energy to propel spacecraft at or above escape velocity from ...
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0answers
17 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 ...
0
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2answers
68 views

Does chemical energy contribute to mass? [duplicate]

Does chemical energy contribute to the mass of an object? I don't mean the bond energy, but the possible energy that could be released (i.e. Does an atom of oxygen and a molecule of hydrogen (H2) have ...
1
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1answer
33 views

How the number of binary collisions increases with centrality faster than the number of participant in heavy ion collisions?

How the number of binary collisions increases with centrality faster than the number of participant in heavy ion collisions at different particle colliders?
0
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1answer
147 views

Nuclear to Electricity Energy Conversion

Currently nuclear power generates heat, which heats water into steam that turns conventional turbines. The energy conversion is as follows: photonic->heat->kinetic->electric This would result in low ...
3
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2answers
185 views

Why is the Spin of the photon neglected?

We know photons have spin s=1. However, in Nuclear physics, the conservation of angular momentum in case of Gamma transitions is employed as follows: $$\vec J_i=\vec J_f+\vec L$$ where $J_i$ is the ...
21
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2answers
2k views

Why is boron so good at neutron absorption?

Why is boron so good at absorbing neutrons? Why does it have such a large target area compared to the size of its nucleus?
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2answers
153 views

In a nuclear reaction, where does the energy go?

Lets say two hydrogen fuse together, where does the energy released go? Is it carried away as momentum imparted on the helium atom? Is it carried away in neutrinos? Is it carried away as gamma rays? ...
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1answer
151 views

Mass loss for Fusion energy? [closed]

I am thinking how you can estimate the mass loss of the fusion energy for 1 kWh. I think you cannot use Einstein's $E=mc^2$ to calculate the mass loss in the fusion reaction of the Sun. How can ...
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1answer
51 views

Characteristic Ka X-rays [closed]

In an experiment one observes the characteristic Ka X-rays of two elements at energies of 6.930 and 7.478 eV. The higher energy line is due to Ni. What element is responsible for the lower energy ...
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0answers
50 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 ...
4
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2answers
147 views

Why do heavy nuclei have half lives

Why do heavy nuclei have half-lives if they are unstable why do they take millions of years to break down in some cases why don't they simple do it instantly? What makes them stay together?
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2answers
144 views

Could I turn into a nuclear bomb?

Just out of curiousity, could the nuclei of our atoms split via quantum tunnelling, thereby leading to nuclear reactions and ultimately turning us into atomic bombs? I know that this is ...
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0answers
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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2answers
19 views

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 ...
2
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1answer
566 views

Why can't electrons be found inside the nucleus if there are infinite number of orbitals?

If there are an infinite number of orbitals, we can assume, that they can be present in any point in space. If that is correct, why do we not find electrons in the nucleus? I study in high school. ...
3
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1answer
22 views

Models for populations of decay products

I'm looking to create a population model for the specific nuclides in a neutron spallation source. The source is a target (Tantalum clad Tungsten) which is being bombarded with protons, and in turn is ...
2
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0answers
33 views

Nomenclature of nuclear excited states

I read in an online portal about $^{112}$Sn nucleus making a transition from $0_{g.s}^{+} \rightarrow 2_{1}^{+}$ state. Also, some higher excited states were named as $0_{2}^{+}$, $3_{1}^{-}$, etc. ...
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1answer
32 views

Notation on chart of the isotopes

I recently purchased a complete chart of the isotopes, (this one: https://shop.marktdienste.de/shoppages/produktuebersicht.aspx ) and have it on the wall next to me in work. The different coloured ...
3
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1answer
98 views

How does neutron reflection work?

What I mean here isn't what is it used for, but what's actually going on with the reflector. There are a lot of sub questions to this. how much energy is lost in the act of reflection. not ...
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0answers
39 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 ...
0
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1answer
50 views

Oscillation of nucleons mediated by polarizing electron charge on opposite ends of the nucleus?

Assuming I have a nucleus and its known that there are nucleons inside its shell. Lets say I have an electron that alternates its position from the top of the nucleus to the opposite bottom, back and ...
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1answer
109 views

What would happen if you split an antimatter nucleus? [duplicate]

If we had the huge money required to make it, could it be used as a weapon more destructive than a regular nuclear bomb? Here it would undergo fission AND annihilate regular particles, so...?
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1answer
49 views

minimum hyperbolic distance for Rutherford Scattering

I saw in a textbook that gave the minimum distance for a hyperbolic trajectory in Rutherford scattering is given by $$r_{min}= ...
15
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2answers
2k views

How to detect a secret nuclear detonation here on the earth?

How can we know that North Korea and Iran (to name a few) are exploding nuclear weapons if no inspectors have ever been granted access to suspected nuclear sites in these countries? How can we ...
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2answers
117 views

How massive can an atom get?

After reading this thread, it appears to me that creating a new element is a game of chance some sort of an art. It also appeared to me that the higher you go, the harder it is to make an element. ...
2
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1answer
44 views

Doubly magic isotopes

I understand the definition of a magic number in nuclear physics to mean a number of either protons or neutrons to completely fill a nuclear shell. I see here the term "doubly magic" used for 78Ni: ...
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2answers
103 views

Gamma spectroscopy - Do annihilation photons produce a backscatter peak?

Below is a diagram of part of a structure which I find in a gamma spectrum taken from a hall in which a neutron source is undergoing spallation. The structure which I'm interested in can be seen ...
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1answer
42 views

Reading ensdf files

I understand that this is more of a computing question, but I still think the appropriate place to ask it is here. The Evaluated Nuclear Structure Data Files are on the internet, available for ...
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2answers
97 views

Color Force & Nuclear Force [closed]

I was wondering if the color force and nuclear force are both sub-forces of the Strong Interaction? If so is the Strong Interaction responsible for any other forces?
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0answers
44 views

Does core of a proton exist? [duplicate]

I understand a proton is made up of quarks/gluons. I want to know if a proton has an actual core? Also whether protons have a core/surface temperature.
2
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1answer
411 views

Gamma spectroscopy - Table of radioactive isotopes with gamma energy search

For anyone doing gamma spectroscopy by hand, the task is considerably eased by tables like this: http://nucleardata.nuclear.lu.se/toi/ Where not only can you search for particular nuclides, but you ...
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1answer
105 views

Why do you need debroglie wavelength less than nucleus diameter to probe a nucleus via deflection? [duplicate]

e.g. you need to give enough energy to electrons to probe a nuclear structure via deflection.
2
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0answers
50 views

Gamma spectroscopy – What is this structure?

What is this strange structure in the gamma spectrum between 450 and 550 keV (below) around the peak at 477 keV? The spectrum seems to rise to a plateau (almost like a small Compton plateau) around ...
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1answer
73 views

Length of time interval for an atom in excited state to drop to lower energy level [duplicate]

This is either a basic question or one that doesn't make any sense, but here goes. If I have an atom in an excited state (1st energy level or 2nd or more), how long does it take to drop to a lower ...
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2answers
101 views

How do protons and neutrons interchange?

I recently read in a book that a nucleon with +1/2 isospin is a proton and if the isospin is changed to -1/2, it is a neutron, so it is the same particle in different states. If a proton has a ...
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0answers
47 views

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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0answers
90 views

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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1answer
155 views

When i tear a paper, can i accidentally create nuclear fission?

I know it's a stupid question... but when I tear a paper i may coincidentally split it and create nuclear fission. When i tried experimenting, by tearing the paper for HELLKNOWS how many times, I ...
7
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2answers
209 views

What is this jump in U235 fission yields?

Is it an artifact? (I have drawn the black line). Or can anybody explain it theoretically? The plot is the "235U Chain 14MeV" provided in the website https://www-nds.iaea.org/ Some sources call it ...
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0answers
7 views

Have the BaF2 scintillator have a strong correlation with the alimentation current that cause the shifting of the centroids?

In gamma gamma correlation I suspect the presence of sistematic error maybe caused by a non optimal alimentation voltage according to someone there is a quadratic correlation between centroids ...
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1answer
71 views

How can a black hole be a cause of a Big Bang? [closed]

Is it possible that Big Bang occurred as a result of the black hole formation - that is the matter compressed so densely that it "exploded" within the boundaries of its horizon and became a what we ...
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0answers
36 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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0answers
18 views

Can an excited nucleus capture a second neutron? [duplicate]

I am wondering if is it possible to have the following scenario: Nucleus captures neutron. Nucleus is excited but does not relax through decay but captures another neutron. Maybe it is possible if ...
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2answers
59 views

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} ...
4
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1answer
94 views

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 ...
3
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1answer
45 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: ...