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

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Proton mass and Weizsäcker's formula

I'm so confused in the use of nuclear masses and atomic masses. I have two questions. From the book "Outline of Modern Physics" by Ronald, I understand that the semiempirical mass formula ...
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420 views

Electric potential energy after nuclear fission

We have a uranium-236 nucleus that fissions into two equal fragments, and I'm supposed to find the electrical potential energy just as the two fragments split apart. No other information is provided. ...
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114 views

Combining of iron nuclei

Iron is the most stable single element (I don't know about combinations of elements, but oh well, not applicable to question). Stars go through cycles where they change the materials of their cores, ...
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1k views

Explanation of energy levels in molecules, atoms, nuclei and their relationship

Why are the energy levels of molecules, the atoms that form them and the nuclei inside the atoms considered separately? Or phrased in a different way- what is it that makes their energy levels so ...
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110 views

Which pion is mediator in nucleon-nucleon interaction

In nucleon-nucleon interactions of n-n, p-p, n-p how do you determine which pion is the mediator?
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187 views

Estimation nuclear force between proton and neutron in deuteron

Is there an estimation of nuclear force between proton and neutron in deuteron to say What is the strong nuclear force between them? 1N? 10N? 100N? 1000N?
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295 views

$\alpha$ and $\beta$-decay, why don't they neutralize each other?

$\alpha$ radiation consist of positive charged helium nuclei, $\beta$ radiation of negative charged electrons. So why don't the $\alpha$ particles take those electrons to get neutral?
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66 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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30 views

Why should odd-ordered electric multipole moments vanish?

In the multipole expansion of the radiation field of a nuclear, it is considered that the odd-ordered poles (like electric octupole) must vanish in order to conserve parity. But there exist many ...
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49 views

The central density of a nucleus remains roughly constant?

Let A be the atomic number The density of a nucleus is computed using the ratio of the number of protons and neutrons, A, to the volume of the nucleus (which at my current level, is assumed to be a ...
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39 views

Proton-Uranium collision

I am looking for references or numbers regarding what happens when one bombards Uranium with Protons. In particular: How to calculate how often does a collision occurs? Can a collision lead to a ...
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57 views

Are nuclear processes the only processes that release more energy than is input?

Are the nuclear processes of fission and fusion the only known processes or events that release more energy than is input to create those processes? I know I am being a little vague; I do not know the ...
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Why are atoms of the same element exactly the same?

Based on what we know about atomic structure all atoms have an electron density function which describes the uncertainty in the position of an electron. Thus theoretically 2 atoms of the same element ...
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Why is 0 $\nu \beta\beta$ decay often written with electron emission and not positron?

According to http://www.cobra-experiment.org/double_beta_decay/ I can see that double $\beta$+ decay is possible, but I often find neutrinoless double beta sources with the double $\beta$- decay ...
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50 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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51 views

Protons (as opposed to neutrons) to mediate nuclear fission?

I am just wondering why are protons (as opposed to neutrons) not used to mediate nuclear fission? Is it because it is charged, so we will have to input more unnecessary energy to overcome the Coulomb ...
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35 views

Internuclear Binding Force: Experimental geometric detail

I am looking for the most precise currently available deuterium potential energy curve (generated purely by experimental data) on the nucleon-nucleon scale. This is crucial. I need a radial ...
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710 views

binding energy of a nucleus is positive?

I have found from this link http://hyperphysics.phy-astr.gsu.edu/hbase/nucene/nucbin.html that: Nuclei are made up of protons and neutron, but the mass of a nucleus is always less than the sum of the ...
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154 views

Ground State Assignment for nuclear shell model

Why is the ground state assignment $0^{+}$ whenever the number of neutrons and protons are both even?
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543 views

Centrality and collision parameter b

Can someone tell me what does it 20-30% collision centrality mean in terms of impact parameter b?
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371 views

What is “Symmetric Fission”?

Dose anyone has a clue what Symmetric Fission is? I couldn't find any explanation on what is it on internet.
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Nuclear reactions and energy conservation

How are nuclear fission and fusion compatible with the law of conservation of energy? During fission $He$ splits into 2 hydrogen atoms along with enormous amount of heat energy and hydrogen also ...
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151 views

Theoretic Mass Energy Conversion?

say you had a large quantity of a heavy element such as uranium... AND you put a massive amount of energy into it, so that it began to undergo nuclear fission and transformed to a significantly ...
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490 views

what is the magnetic quadrupole operator?

To find magnetic or electrical moments in quantum theory we must calculate the expectation value of an appropriate operator. the dipoles operator are similar and is easy to find but the magnetic ...
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433 views

How to superimpose Wood-Saxon and Coulomb potential?

I have just written a simple simulation that models the tunnel-effect of alpha-particles for $^{212}$Po and $^{238}$Ur. In this simulation, I approximate the potential of the nucleus by a simple ...
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What does the Atomic Form Factor means?

I was reading about Nuclear Physics and the autor mentioned something about the Atomic form factor, something relationated with the Fourier Transform of the espacial distribution of the electric ...
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110 views

Nuclear transition notation

I have a question which asks me to determine what x is for the following nuclear transition $$^{29}Si(\alpha, n)X$$ But I don't have any idea what this notation implies. Another example: ...
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115 views

Stability of nucleii and $A=5$

Why there is no stable nuclei with $$A=5$$ in nuclide the chart and so in nature like we know it?
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512 views

Muon production in particle accelerator

PAMELA is a particle accelerator which have two concentric rings, protons are accelerated in the inside ring. At ISIS muons are produced when a 800 MeV proton beam collides with a graphite ...
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About Efimov States and Halo-Nuclei

I read that Halo nuclei could be seen as special Efimov states, depending on the subtle definitions. (The last sentence in the second to last paragraph of this Wikipedia article.) This does ...
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172 views

How does the curiosity rover get it's power? [duplicate]

Possible Duplicate: Mars Curiosity Power System I found a web page that said it uses Plutonium. I am sure it's not based on fusion or fission. What is the basic idea on which the power ...
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55 views

Total energy of neutrons and protons

In a stable nucleus, are the total energies of neutrons and protons same?
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42 views

Spin, isospin, parity etc. in nuclear physics

I have one question regarding these quantum numbers. When I read through my textbook, it sometimes just says something like: "And this atoms ground state has $J^{\pi} = 0^+$ and isospin $+1$" - as an ...
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63 views

What are “correlations”?

When working with realistic two-body hamiltonians, a direct diagonalization is almost always imposible. Thus one usually takes a procedure which yields an approximate solution. A well known approach ...
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Resultant half life of sample which contain more than one type of radioctive element.

If a sample is mixed with more than one radioactive elements - for example Ra-226, Po - 210 and Cs -137, then how to estimate the resultant half life of the sample? Is there any general formula to ...
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48 views

Protons and Neutrons Overshoot Actual Mass? [duplicate]

When I add up the mass of 6 protons and 6 neutrons in amu, I get a mass that is greater than the mass of carbon. I thought that it should be the other way around, because I have not including binding ...
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56 views

Can we predict the half-lives of radioactive isotopes from theory?

Is there any way to predict the half-lives of radioactive isotopes from theory (that is, using only theoretical considerations, without using data about the decay)? For example, could we predict that ...
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76 views

Sommerfeld Parameter Confusion

In almost every reference site I can find, the Sommerfeld parameter $\eta$ is explicitly stated as $$\eta=\frac{Z_1Z_2e^2}{\hbar \nu}=\frac{Z_1Z_2e^2}{\hbar }\sqrt{\frac{\mu}{2E}}$$ Where $Z_1$ and ...
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86 views

Deuteron wave function

The deuteron wave function is given by $$|\psi _d\rangle = a|^3S_1\rangle+b|^3D_1\rangle$$ where all states are normalized. How do we find $b^2$ s.t. the wave function reproduces the magnetic moment ...
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57 views

Why ingoing and outgoing impact parameters equal in elastic scattering?

Take the Rutherford scattering, as for example in this picture: What is the easiest way to show that the impact parameter "b" (see picture) is the same for the ingoing and outgoing trajectories? ...
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199 views

How hot is Plutonium-238 in Radioisotope Thermoelectric Generators (RTGs)?

As I understand it, Plutonium-238 is used to provide power through heat generation in radioisotope thermoelectric generators. My question is... how hot is a pellet of Plutonium-238? Does the heat ...
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81 views

Chemical potential for nucleons

Do you know if the concept of chemical potential can be properly defined for nucleons in the nuclei? I mean, if I can picture the nuclei like an interacting gas of nucleons, then may I think of a ...
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149 views

Isospin quantum number for light nuclei

Does anyone know where I can find the Isospin values for light nuclei (H, C,N, O, S, Cl, ..) in their ground state?
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171 views

How to calculate scalar neutron flux

I am really confused about the difference between flux and scalar flux. I have a specific question: If we have a parallel neutron beam of strength $\phi_0$ given in neutrons/cm$^2$s, incident on a ...
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48 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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58 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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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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144 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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Which nucleus is the most resilient against gamma-induced fission?

To state the title question perhaps more precisely: What is the largest photon energy $E_{\gamma}$ and the corresponding mass number $A$ and atomic number $Z$ of a suitable nucleus ${}^A_ZX$ ...
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62 views

Nuclear fission mechanism: neutron capture

Consider this nuclear fission reaction: $\mathrm{^{235}U+{}^1n\to{}^{236}U \text{ (excited)}\to{} ^{92}Kr+{}^{141}Ba+3{}^1n}$ I have not understand why a thermal neutron ($^1$n with $E\simeq 0.025$ ...