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

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About Nuclear magnetic resonance

I'm trying to understand the basic principles of Nuclear Magnetic Resonance reading this link but I have some doubts: 1) I have ever known that when protons aren't in a magnetic field, their spins ...
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Leakage of X-ray radiation

Suppose a sample of strontium-90 is stored in a lead container with lead walls. It is know that X-ray radiation may be detected outside the lead container. After some discussion with my peers, it ...
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26 views

Working of fusion reactor

The present type fusion reactors use the magnetic confinement technique for the production of energy. Moreover only 48% for the energy is only absorbed and converted into useful energy . Why we are ...
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631 views

Miniature Neutron Stars?

Is the nucleus of a carbon atom, for example, as dense as a neutron star? I read that neuton stars also contain protons. Thinking more broadly, are we surrounded by quadrillion of quadrillions of ...
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44 views

What is relationship between Quantum tunnelling and Gravitational potential energy of stars?

Are there a direct mathematical relationship between Quantum tunnelling and Gravitational potential energy of stars? The true source of the Sun's energy was shown by Hans Bethe to be nuclear fusion ...
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393 views

Anti-neutrons, anti-quarks, isospin: What is observed and what is derived?

I would be a little more restrained with the existence of antineutrons. First at all - if I understood right - the existence of antiquarks is hypothetical. If one not agree with this please refer to ...
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59 views

Cobalt 60 beta decay

In the beta decay of an atom of Co60, the radiation you would expect is one or two gamma rays, plus an electron plus an electron neutrino (and in the nucleus Ni60+, if I understand it well). However, ...
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23 views

Dual and Multiple scattering of protons in light elements

I was wondering whether dual large angle scattering and multiple small angle scattering is of great significance in proton colision with light nuclei in comparison to heavy nuclei. For instance given ...
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31 views

Does the relative angular momentum of the nucleons contribute to the spin of the nuclei?

Imagine we have a nucleus. We do talk about spins of nuclei. Is this spin the total angular momentum of the nucleus, that is, spins and relative angular momentum of all of the nucleons? If so, why? ...
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173 views

Why can't electrons fall into the nucleus?

I read a book on pop sci book on quantum mechanics and the author said that electrons do not fall into the nucleus due to quantum mechanics- which principles suggest this (I think it was Heisenberg's ...
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70 views

Hydrogen Bomb Mass to Energy?

How much mass is converted to energy when a hydrogen bomb explodes? I remember an eighth grade chemistry class where, by going through the nuclear processes, my teacher estimated that roughly 2g of ...
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52 views

Nuclear fission difference in energy calculation?

If you have a uranium atom of radius $10^{-14}m$ that undergoes fission into two fragments each with 46 protons and radius $8\times10^{-15}m$. There are two ways you can calculate the electrostatic ...
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94 views

Radioactive decay - What mechanism decides when an unstable nucleus decays?

My first question on Stackexchange (if it is formatted wrong or something please tell me so I know in future) - here it is: Given an unstable nucleus (exactly which nucleus is not particularly ...
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What is the difference between Linear and Non-Linear Magneto-optical effects?

Principle difference between Linear and Non-Linear Magneto-optical effects and how they affect the property of light passing through a Vapor medium.
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115 views

Theoretical Stability of “AB-matter”

Alexander Bolonkin has proposed the possibility of manipulating nucleons to produce stable, macroscopic structures of nuclear matter at zero pressure (which he calls "AB-matter"), by analogy with the ...
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1answer
43 views

Calculate minimum energy of incident neutrino using Mandelstam variables

I am studying the following nuclear reaction: $v + \tilde{v}\rightarrow Z^0$ where the antineutrino is motionless and has a given mass. The $Z^0$ boson has also a known mass. I'm trying to calculate ...
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70 views

Question on spin-orbit interaction

When you study the spin-orbit interaction in quantum mechanics, even for a simple hydrogen atom, you find only the electric field in the nucleus reference system, while in the electron reference ...
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1answer
38 views

Does a lack of windows protect against shockwave of a nuclear attack?

I know that one of the dangers of a nuclear attack is the shockwave which compresses the air and can cause a pulmonary embolism in creatures in the area of effect. Is the shockwave directional in ...
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1answer
38 views

Can we use water as fuel for nuclear thermal space propulsion?

As I know, the working fuel of choice is Hydrogen because of its low molecular mass. When it comes to escape velocity, the estimate vary too much, from $8$km/s to $50$km/s (gas core reactor). ...
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59 views

Ionization by heating

I would like to ask what happens if an atom exposed to a very high temperature - say millions of degrees (Kelvin). Can we use heating to separate electrons from their nucleus? And what happens to the ...
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69 views

Norsk Hydro and heavy water - what was the perceived threat?

Through various raids and acts of sabotage during WWII, the Allies succeeded in preventing Germany from coming into possession of large quantities of heavy water produced by the Norsk Hydro plant in ...
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68 views

Advanced Molten Salt Reactor - Is the concept of designing a reactor that uses spent nuclear fuel to generate power technically feasible?

I was going through the concept of designing a Nuclear Reactor that uses Spent Nuclear Fuel(SNF) to generate power as proposed by Transatomic Power . ...
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36 views

Lifetime of undiscovered element and its calculation

Reading about nuclear models, nuclear physics and the mythical ``stability island'' I just wondered about the next question: How can the lifetime of any undiscovered superheavy element be calculated ...
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Why does the Sun's (or other stars') nuclear reaction not use up all its “fuel” immediately?

The temperature and pressure everywhere inside the Sun reach the critical point to start nuclear reactions - there is no reason for it to take such a long time to complete the reaction process. Just ...
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How the Bloch sphere of a Hahn echo in NMR looks like? 90-t-90-t-echo

I have tried to find in the literature a proper nice and beautiful Bloch sphere to describe the trajectory of a nuclear spin, starting in z-axis, using a pulse sequence of an initial 90º pulse with ...
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72 views

For which temperatures are the ENDF cross-sections given?

In ENDF there are cross-sections given for different types of nuclear interactions. For example, this file gives the cross-sections for different neutron energies. However, it is not clear, which ...
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81 views

Why are atomic quadrupole moments calculated using nuclear spin?

It's my understanding that electric quadrupoles interact with the gradient of an electric field, and I understand roughly how this works. I am trying to calculate the interaction between an atomic ...
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84 views

Why is binding energy $\Delta mc^2$?

As we know the mass-energy equivalence relation $E=mc^2$ originally came from special relativity. And the binding energy is $\Delta mc^2$. How do we know that the extra mass coming from theoretical ...
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35 views

What is the distribution of energy between the alpha, beta and gamma particles emitted in nuclear fallout per one RAD?

I have been trying to find a relation to be able to convert from RAD to REM. What I found is that I need to know the "quality factor" as some sources call it, which is the effect of different ionizing ...
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1answer
28 views

Critical size and Radioactive Nuclei

Nuclear fission requires the mass of the fissile material above the critical mass. So that the explosion takes place at least in the case of a nuclear bomb. But once a single nucleus got involved in ...
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183 views

What causes radioactivity? Is it a quantum mechanical effect?

I'm just curious what causes radioactivity. I've been told that in the case of alpha decay, since the nucleus is quantum mechanical, there is a probability that the configuration of protons and ...
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64 views

Why is Silver-108 unstable

Why is Silver-108 unstable if silver-107 and silver-109 are stable? I found it on crash course but no answer was given.
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67 views

Strength of strong nuclear force vs distance?

Is there at least an approximation of the decrease in strong nuclear attraction vs distance from the center of the nucleus?
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799 views

Why did nuclear testing not result in nuclear winter?

According to Wikipedia over 2000 nuclear tests have been performed since the Manhattan Project. If nuclear war would bring about a nuclear winter, why didn't testing do? Were they too much spread out ...
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39 views

Blazars and nuclear physics!

How are studies on blazars related to the field of nuclear physics? Should these not purely belong to Astrophysics? Just inquisitive.
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Why does the Walecka model not include pions?

The Walecka or $\sigma$/$\omega$-model is an effective theory describing nucleon-nucleon interaction by an exchange of $\sigma$/$\omega$-mesons. Why does it not include interactions by pions?
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Is fission reaction considered natural or artificial? [closed]

As I learned, nuclear fission doesn't occur without the control of a human made nuclear reactor, by hitting a neutron to a fissile isotope. Thus, the fission reaction is considedred as a part of ...
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Does Uranium-235 always split into Krypton and Barium in nuclear fission?

In most nuclear fission examples and exercises, the products of a nuclear fission of Uranium-235 are two light nuclei of Krypton and Barium: $$\mathrm{ _0^1n + U \longmapsto Kr + Ba + energy }$$ Is ...
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89 views

Is there still mystery about spin crisis?

The gluon is a vector boson; like the photon, it has a spin of 1. If this is true and if we know the spin of protons and neutrons then why the news SPIN COMES FROM GLUONS? is telling that, we ...
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Why do almost all nuclear reactions release energy?

I'm just wondering why almost all nuclear reactions release energy, in a typical way, the mass defect is transformed into energy ? Is there a nuclear reaction that gains mass (resp. energy)? or most ...
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Why is the spectrum of the $\beta$-decay continuous?

the spectrum of the Gamma and Alpha decays are both discrete, i.e. the $\alpha$-particles and the $\gamma$-rays take on only discrete values when emitted from a decaying nucleus. Why is it then, that ...
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Thorium based nuclear reactor [closed]

My question is how thorium works as a radioactive nuclear fuel and what are the special properties of thorium based nuclear reactor.
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22 views

Nuclear Compton Scattering Data

Is there a repository where one can find unpolarized nuclear Compton scattering data $\gamma (Z,N)\rightarrow \gamma (Z,N)$ for specific nuclei $(Z,N)$? or even some parametrization of structure ...
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32 views

Nuclear explosion wavelength data

I am looking for data source (or chart) of spectral data that is being emitted on detonation of nuclear or thermonuclear explosion. Reason I am looking is to see if this data has specific signature ...
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92 views

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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42 views

Explosive energy in a container [closed]

What happens when the explosive energy of a grenade or a bomb is contained in a container, if you will, and no energy can be released through the container in the form of heat or sound etc...? Just ...
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66 views

Radioactive decay law and the exponential model, is it always valid?

The law of radioactive decay reads $$ N(t)=N_0e^{-\lambda t}$$ Is it valid when there is less than 1 nucleus or particle to decay? Obviously, it is nonsense to consider that we have 1/2 of nucleus ...
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1answer
37 views

Totally antisymetric wavefunction: clarification about terminology

Pauli's Principle says: "The wavefunction of two identical fermions must be totally antisymmetric". I know that, for a antisymmetric wavefunction, $(-1)^L*(-1)^{S+1}*(-1)^{I+1}=-1$ "totally ...
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1answer
52 views

Parity of a system composed of 2 particles

I have read that for a system of 2 particles, the total parity is given by: $P=P_1 P_2 (-1)^L$ where $ P_1, P_2$= insisec parity of particle 1, 2 $L$ = relative angular moment what's the meaning ...
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Is the half-life of Primordial Nuclide determine only by the age of the earth? [closed]

Is the half-life of Primordial Nuclide determined only by the age of the earth? Or are their other age defining considerations? The point of the question is to know that the only reason that we have a ...