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

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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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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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Derivation of the kinetic energy of decay product [on hold]

By conservation of momentum: $$M_{\alpha }V_{\alpha }+M_{Y}V_{Y}$$ By the conservation of energy: $$(\frac{1}{2})M_{\alpha }V_{\alpha }^{2} + (\frac{1}{2})M_{Y }V_{Y }^{2}$$ Here I begin the ...
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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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1answer
123 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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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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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
20 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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1answer
21 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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44 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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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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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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Is the speed of sound almost as high as the speed of light in neutron stars?

Have you ever wondered about the elastic properties of neutron stars? Such stars, being immensely dense, in which neutrons are bound together by the strong nuclear force on top of the strong gravity ...
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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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2answers
44 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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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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1answer
90 views

What is the difference between zero background radiation and field background radiation in Nuclear Physics measurements?

Can someone please explain the difference between these two terms (Zero Background Radiation and Field Background Radiation) used in radiometric prospecting measurements?
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61 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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2answers
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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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1answer
175 views

Proof of Bethe-Bloch stopping power

I want to prove the Bethe-Bloch stopping power formula but I don't know where to start. Any one can offer a book or paper? Related: http://en.wikipedia.org/wiki/Bethe_formula
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2answers
70 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
34 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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48 views

The Internal Structure of A Nucleon [duplicate]

Just like, in a Bohr model, the atom has a particular structure, what is it like inside of a nucleon? Like, are there particular ways the quarks are arranged, and what about the binding energy that ...
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2answers
571 views

If we assume that protons don't decay, then will all matter ultimately decay into Iron-56 or into nickel-62?

Wikipedia says that all matter should decay into iron-56. But it also says Nickel-62 is the most stable nucleus. So could this mean that in the far future, everything could (through quantum ...
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An atomic bomb explodes inside of an “unbreakable” container which is on a scale. Does the “weight” of the container change?

This may or may not be an incredibly stupid thought experiment, but a short time ago I read that most of the "mass" in the proton was actually energy from the quarks and gluons, as opposed to the ...
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The “binding energy” of bonded particles adds mass?

This is a follow-up my previous question. Several of the answers indicated that the mass of a particle (atom, proton, etc.) increase with the "binding energy" of it's component particles - the energy ...
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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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Why does fusion stop at iron when nickel is most tightly bound?

My understanding is that stellar fusion naturally stops at iron because it is energetically unfavourable to grow the nucleus further. But iron is only the third most tightly-bound nucleus, nickel is ...
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6answers
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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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1answer
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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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What is the lowest possible theoretical temperature that nuclear fusion can occur at?

I am not talking about the pseudo-science of so called cold fusion I am interested in what temperature you can get away with to produce fusion reaction. I was thinking in terms of micro-fusion or at ...
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22 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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3answers
48 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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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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Can I move the atom nucleus only?

I was wondering if it is possible to move the atom nucleus and leave behind the electrons? I can imagine that the electrons will follow the nucleus. But what if the speed of the nucleus is almost the ...
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1answer
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Can only radon-222 decay into polonium-218?

Is radon-222 the only element that can decay into polonium-218?
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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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1answer
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What is the main thermal energy source for a protostar, the contraction or the deuterium burning energy?

According to the virial theorem, when a protostar contracts, half of the gravitational potential energy is radiated and half is kept as kinetic energy of the falling material which in turn heats the ...
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0answers
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Electron Beam Welding equation

I am studying for a nuclear physics course right now and came across a question and topic that sparked my interest - Electron Beam Welding. As I understand it, the process heats up the metal by ...
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1answer
32 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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0answers
12 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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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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3answers
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Does the Breit Wigner formula apply to intermediate virtual particles?

Breit Wigner Formula describes the cross section for interactions that proceed dominantly via a intermediate particle (O*) A+B → O* → C + D: $$σ = \frac{2\Pi}{k^{2}}\frac{Γ_{i}Γ_{f}}{(E-E_{o})^{2} + ...
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3answers
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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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1answer
179 views

Nuclear fission or fusion occurring at or near the speed of light

Suppose a device or object were traveling at or near the speed of light, and fission or fusion occurred while in this state of motion, creating an enormous blast, what would occur? Would this cause an ...
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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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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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Origin of elements heavier than Iron (Fe)

In all the discussions about how the heavy elements in the universe are forged in the guts of stars and especially during a stars death, I usually hear that once the star begins fusing lighter atoms ...
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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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1answer
171 views

What was Feynman's famous formula?

In Welton(1983), Memories of Feynman, Welton mentions two formulas which he denotes as Feynman's Famous Formula (FFF) and FFF #2. Which famous formulas is he talking about? Is he maybe talking about ...