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

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Gamma decay with lowest energy?

What is the (by current knowledge) least energetic example of a gamma decay into the nuclear ground state? I am only considering degrees of freedom of the nucleons, i.e. without the electrons. (I ...
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181 views

Feynman-Bethe Critical Mass Formula

According to the historical lore of the making of the atomic bomb at Los Alamos, Richard Feynman and Hans Bethe supposedly worked out a formula for the critical mass for the core of the A-bomb. Is it ...
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51 views

How to determine whether a nuclear transition would be electric octupole, or hexadecapole?

The transition from one nuclear state to another is classified as quadrupole/octupole, etc, depending on the units on angular momentum transferred. But depending on the angular momentum of the two ...
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59 views

Origin of internuclear forces

I just recently read about the existence of internuclear forces as the reason for the nucleus to remain 'stable' as in it doesn't separate out into protons and neutrons even though there is electronic ...
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210 views

Does water absorb neutrons?

Water is used as a shielding material in nuclear reactors. What's its function as a shield? Does it absorb neutrons and is there a reaction between water and neutrons?
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158 views

From which height the effect of nuclear bomb will be Greater?

Well I was wondering like during war some of them drop nuclear bomb on ground and then it explode and we see a huge blast which causes so much of destruction but my question is that is it possible ...
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74 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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80 views

conversion from atomic mass to nuclear mass in the calculation of Q-values in a beta decay

Not exactly a homework problem in the real sense of the word but a way to understand how I can make arrive at the Q-values algebraically without relying on formula sheets or memorising. Let's begin ...
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154 views

Stability of nuclides in regard to the forces acting upon its nucleus

I am having trouble piecing together some information regarding the stability of a nucleus. I have read that iron-56 is the most stable isotope, because it has the highest binding energy per nucleon ...
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309 views

Coupling fission and fusion and disappear all mass. Why doesn't this happen?

I'm confused about the fact that in a fission process the masses of the "products" are less than the mass of the "reactants". And in a fusion process the masses of the "products" are less than the ...
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32 views

How does one decide if the process if beta decay positive or beta decay negative?

I've been given a sample and a daughter product and I'll have to write down the other products of this decay process. This is a beta decay due to the mass number A being constant in the sample and the ...
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45 views

Coulomb barrier in nuclear fusion

Suppose there exists an alpha particle in the nucleus. Within a radius of 2 femtometer, the dominating force is the nuclear force but beyond this radius, the Coulomb force becomes the effective ...
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27 views

Nuclear powered flux compression generator?

A flux compression generator is a device for converting the chemical energy of explosives into magnetic field energy, with reported efficiencies of up to 20%. Is there a limit on the conversion ...
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32 views

Trying to locate information on alpha particle scattering/peak resonance energies for elements

On our campus we have an ion beam analysis lab. It is used for compositional analysis through the firing of alpha particles at MeV energies at target samples. From here it is a simple matter of back ...
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45 views

What processes contribute to non-relativistic proton-antiproton collsions (annihilation)

I wonder what the dominant contributions of nuclear interaction to non-relativistic proton-antiproton annihilation are (I mean that the proton and antiproton are non-relativistic. The products might ...
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1answer
104 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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38 views

An example on computing the density of a typical nucleus

An example from my text is as such: Compute the density of a typical nucleus, and find the resultant mass if we could manufacture a nucleus with a radius of 1cm. I will only provide a partial ...
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55 views

Radioactivity, alpha decay [duplicate]

In alpha decay, a $\text{He}$ nucleus is emited along with a daughter nuclide. Now suppose $\text{U}$ with atomic number 92 and atomic mass 238 emits an alpha particle and a daughter nuclide is formed ...
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585 views

Why do only heavy radioactive elements perform fission or fusion?

Why do only heavy radioactive elements perform fission or fusion? I mean what's so special about heavy elements which makes them ideal for nuclear fission? Also why do only neutrons show ...
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67 views

Scattering and form factor

In Introductory Nuclear Physics by Krane (there's a PDF online), it is mentioned electron scattering on the nucleus to get a picture of the latter's shape, e.g., its radius. It is said the probability ...
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118 views

Two isobars they differ in binding energy, will they differ in radius as well?

It is a problem from introduction to nuclear physics- by krane, chapter: nuclear properties, problem 7. It goes like this: From the known masses of $_{~~8} ^{15}\rm O$ and $_{~~7}^{15}\rm N$, compute ...
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80 views

Stopping a nuclear missile

I had been thinking about whether it is possible to stop an incoming missile or not. I found something quite interesting here. So, there many people said that it will be possible to stop an incoming ...
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39 views

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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104 views

Nuclear fission problem

If during a nuclear fission U(235) decomposes into Xe(140), Sr(94) and n(1), how is it possible that the original U(235) has bigger mass than the three resulting nuclei together? Should it not be the ...
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354 views

What Happens to electrons after Alpha Decay and Nuclear Fission?

Where do the electrons go? In alpha decay do 2 electrons follow the alpha particle and make stable Helium or does the larger daughter nucleus become an anion? Also what do the electrons do in the ...
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2answers
126 views

Can an element decay into an infinite loop?

I've been working on a problem and have been wondering is there any isotope of any element that beta decays under certain conditions but then under differing conditions the daughter nucleus electron ...
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1answer
50 views

Is it possible to create helium atoms by bombarding heavy water with neutrons?

If heavy water is bombarded by neutrons is it possible that any of the deuterium atoms can capture neutrons and transmute to helium atoms? I suspect the more probable event would be knocking protons ...
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35 views

Production of Inductively Coupled Plasma

I am working on an experiment hat requires the usage of inductively coupled plasma, but unfortunately, I do not have any equipment at the moment that can produce such plasma, and I really need your ...
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What will happen if a ball of ice with the mass of sun is thrown into the sun?

The question is a bit unrealistic with its circumstances but lets assume there is a bucket of ice cooled down to about absolute zero and is about 1000 km away (all around the sun) from sun and moving ...
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269 views

Does lithium-6 “decay” when hit by a neutron?

I am talking about the nuclear reaction $$ ^6\text{Li} + n \rightarrow\ ^4\text{He} +\ ^3\text{H} + 4.78\text{MeV} $$ A neutron hits a lithium-6 nucleus and together they form an alpha and triton ...
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226 views

What is nuclide notation referring to? Only the nucleus or the whole atom?

sorry that this is an easy question but I am just a bit confused about nuclide notation. When you say e.g. $^{240}_{94}\text{Pu}$, are you referring to the atom of $\text{Pu}$ or only its nucleus? It ...
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Why do all the atoms of a radioactive substance not decay at the same time?

Why does the substance decay at a rate which is proportional to the amount of the substance at that moment? As all atoms are in hurry to become a stable atom and as their decay do not depend on any ...
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99 views

Can only radon-222 decay into polonium-218?

Is radon-222 the only element that can decay into polonium-218?
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174 views

Do hadrons only interact via strong interaction?

According to my revision guide baryon and mesons always interact via the strong interaction. Does this hold for baryon-baryon interactions? meson-meson? Thanks
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104 views

Asymmetry Term in the Semi-Empirical Mass Formula

Could someone explain to me in simple terms what the asymmetry term means and how it is derived. I don't really want a full fledged mathematical derivation, but more the basic principle and idea ...
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59 views

Klein-Nishina for estimating X-ray cross section

I'm looking at interaction probability for X-rays with water and DNA, and recently have starting reading up on the Klein-Nishina identities for differential cross section. When integrated over all ...
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62 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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3answers
118 views

What triggers a nuclear chain reaction?

A nuclear fission works by spliting atom's neutrons by neutrons which release energy but how is the chain reaction triggered because at first the nucleus is bond by a strong nuclear force so what ...
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501 views

Energy from 1 gram of fuel in a nuclear power plant?

It might go without saying, but I am asking about a fission reactor. I assume the fuel still has mass after it is used. If I am right about that, I can't use e=m*c^2 to answer my question. Hence my ...
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116 views

BINDING ENERGY OR BINDING ENERGY PER NEUCLEON REMAINS CONSTANT [duplicate]

Which one is constant BINDING ENERGY or BINDING ENERGY PER NEUCLEON? I GOT LOTS OF ANS. BUT I CAN`T UNDERSTAND. IS NEITHER OF THE IS CONSTANT?
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28 views

Why doesn't the electron fall into the nucleus? [duplicate]

Electrons move around the nucleus, which contain protons and neutrons. I know that quantum mechanics tells us that the nucleus is made up of fundamental particles, but why (quantum mechanically ...
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281 views

Gamow peak and nuclear reaction rate

It's known that the nuclear reaction rate (inside a Star) can be determined with $$R_{ab}=n_a n_b\left<\sigma v\right> \, \approx \, n_a n_b \Big(\frac{8}{\pi m_e}\Big)^{1/2} ...
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55 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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1answer
90 views

Why do nuclear bomb explosions create an array of visible electric discharges in the form of lightening in the upper atmosphere?

I've seen videos on the internet, showing nuclear bomb test explosions, and there appears to be a large amount of visible lightening discharging numerous times over the development of the mushroom ...
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33 views

Regge trajectories for higher spins

I have read that Regge theory did/does predict higher spin meson states, but that at higher spins the data becomes fuzzy for spins greater than 4. Why is this so? In the book "A Brief History of ...
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Why U235 over U238?

There are 3 isotopes of uranium that can be found in nature[1]: U234, U235 and U238. For a chain reaction to last there must be a high amount of neutrons contents and by comparison, U238 contains 92 ...
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110 views

Discrepancy problem in lithium?

Why is there a discrepancy between the amount of lithium-7 predicted to be produced in Big Bang nucleosynthesis and the amount observed in very old stars?
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131 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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71 views

Carbon-14 formation in atmosphere

Wikipedia says Carbon-14 is formed in the atmosphere by the reaction: 1n + 14N → 14C + 1p This looks like neutron capture. However, I would expect neutron capture to result in 15N. However, "proton ...
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Semi-empirical mass formula

The mass formula is given by $M(Z,A) = ZM_{p}+(A-Z)M_{n}-a_{1}A+a_{2}A^\frac{2}{3}+a_{3}\frac{Z(Z-1)}{A^\frac{1}{3}}+a_{4}\frac{(Z-A/2)^2}{A}+a_{5}A^\frac{-1}{2}$ So I am just wondering here what ...