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

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Proton-Neutron Lattice as a form of matter?

Would it be possible for a lattice of protons and neutrons (I'm picturing a plane of hexagons in my head) to exist bound by the strong nuclear force (not gravity)? I know that the strong force losses ...
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525 views

In the known universe, would an atom not present in our periodic table exist?

I have watched this movie Battleship. In it the researchers say this piece of metal is alien because we cant find this metal on earth. So that would mean somewhere else in the universe any of the ...
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113 views

In what environments can a dipolariton form?

In what environments can a dipolariton form? The article in Science in which it is introduced discusses it in the context of an optical cavity in a semiconductor. Can this quasiparticle occur ...
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3answers
167 views

How do we know that internal conversion creates no intermediate photon?

I've read, from several sources, that in internal conversion -- an excited electron transferring its energy to another electron which is then emitted -- no intermediate gamma radiation is produced. ...
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Why are alpha particles made of 2 protons and neutrons?

When experiencing alpha decay, atoms shed alpha particles made of 2 protons and 2 neutrons. Why can't we have other types of particles made of more or less protons?
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76 views

Boiling water reactor

What are the typical power densities in conventional boiling water nuclear reactor per cubic centimeter of fission material?
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304 views

Angle of deflection of an atomic nucleus [closed]

when firing a proton (for example) to an atomic nucleus, from a distance $D$, the deflection angle of the proton $\alpha $ to the type of changes atomic nuclei? or always constant?
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3answers
499 views

Do neutron stars reflect light?

The setup is very simple: you have a regular ($1.35$ to $2$ solar masses) evolved neutron star, and you shine plane electromagnetic waves on it with given $\lambda$. Very roughly, what shall be the ...
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2answers
840 views

Nuclear reactor control rods

What is the relation between control rods surface exposed into a nuclear reactor and neutron energy? Is it linear? I mean, how do neutron absorbing rate change with the progressive immersion of ...
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1answer
753 views

Relationship between nuclear spin and nuclear magnetic moment?

We know that nuclear magnetic moment can be expressed in terms of the expected value for nuclear spin as: $$\langle\mu\rangle =[g_lj+(g_s-g_l)\langle s_z\rangle]\frac{\mu_N}{\hbar}$$ (Cf. Krane), ...
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2answers
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“Dear radioactive ladies and gentlemen” - Letter by Wolfgang Pauli

In 1930, Wolfgang Pauli wrote a letter to Lise Meitner for a convention in Tübingen, considering the problem of beta decay. Does anybody know, where to find the original letter online ?
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2answers
470 views

Russian Doll Teller Ulam?

Can you trigger a thermonuclear explosion from a smaller thermonuclear explosion in a scaling way, so that starting from a small laser ignited fusion within a small fissile container, using the X-rays ...
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3answers
225 views

Could we prove that neutrinos have mass by measuring their gravitational signature?

It is now said that neutrinos have mass. If an object has mass then it also emits a gravitational field. I appreciate the neutrinos mass is predicted to be small, but as there are so many produced ...
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207 views

How was Be-8's Half-Life of 7E-17 Second Determined?

Radionuclides occur with half-lives in a vast range of over 37 magnitudes as listed in this site. In question 7584, Lubos Motl explained how Gyr half-lives were determined. This method doesn't appear ...
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0answers
50 views

Problem on nuclear physics radioactivity [duplicate]

Possible Duplicate: How do we know that C14 decay is exponential and not linear? Please help me solving this problem. Find the half life period of uranium-238,if one gram of it emits ...
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2answers
507 views

Why do we use only nonrelativistic equations in nuclear physics?

What is limit between relativistic and non-relativistic equations? Which conditions do we have to use one of these?
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0answers
133 views

What forms are theoretically predicted for orbitals or quarks in hadrons and of hadrons in tritium?

We all know very illustrative spatial representations of predicted electron orbitals in atoms which are essentially spatial plots of the solutions of wave equations. In all atoms the electrons occupy ...
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8answers
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What practical issues remain for the adoption of Thorium reactors?

From what I've read on thorium reactors, there's enormous benefit to them. Their fuel is abundant enough to power human civilization for centuries, their fission products are relatively short-lived, ...
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1answer
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How did Enrico Fermi calculate the classical Fermi Problem?

From Wikipedia: Fermi was known for his ability to make good approximate calculations with little or no actual data, hence the name. One example is his estimate of the strength of the atomic bomb ...
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0answers
82 views

How can I determine the feasibility of Pd(d,f) fission chains?

The conclusion of this paper (p. 6) discusses some hypothetical Pd(d,f) yields as a possible explanation for anomalous results that the author observed. Suspending disbelief in the data reported in ...
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3answers
1k views

What happens if we put together a proton and an antineutron?

A hydrogen nucleus consists of a single proton. A 2-hydrogen (deuterium) nucleus consists of a proton and a neutron. A tritium nucleus consists of a proton and two neutrons. This makes me wonder how ...
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2answers
188 views

Nuclear physics from perturbative QFT

Is there a renormalizable QFT that can produce a reasonably accurate description of nuclear physics in perturbation theory? Obviously the Standard Model cannot since QCD is strongly coupled at nuclear ...
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0answers
227 views

Any undergrad exercises about nuclear bomb design? [closed]

Are there any handy exercises about nuclear weapon design that are suitable for advanced undergrads in a nuclear physics or similar level physics course? I'm most curious about questions that ...
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4answers
6k views

Where do electrons get their ever-lasting circulating energy?

We all know (or maybe know) that to move, we need to spend energy. If you want to drive a car, you gotta spend gasoline. We also know that energy can't be created (first law of thermodynamics, and ...
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1answer
1k views

How does electron capture occurs?

Electron capture is a kind of decay by which a nuclear transformation takes place. Below is an example of it. $$ _{29} ^{64} \text{Cu} + e^- \rightarrow _{28}^{64} \text{Ni} $$ Of course, nucleus ...
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1answer
223 views

Can stable nuclei theoretically fission through quantum tunneling?

As I understand it, an unstable nucleus is going to randomly fission because the forces binding it together are momentarily weaker than the electrostatic repulsion of the protons. Given that some ...
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5answers
388 views

Why is storage of spent nuclear fuel dangerous?

Just what the title states; there's a good deal of noise made about transport, and storage of spent nuclear fuel. Why all the hullabaloo when the fuel is all spent?
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332 views

Does neutron radiation form clouds?

I've heard a couple of scary stories from experienced accellerator physiscists about something called neutron clouds. Apparently, if you have an experiment like a fixed-target experiment that produces ...
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230 views

How would nucleosynthesis be different if the neutron were stable?

If the strong nuclear force were just 2% stronger, the neutron would be a stable particle instead of having a half life of about 13 minutes. What difference would that have made to Big Bang ...
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1answer
360 views

Island of Stability

When I was much younger, I remember being fascinated by the thought of an Island of Stability at very high atomic numbers. However, I have not heard much on this and I was wondering Did this idea ...
3
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1answer
400 views

Why the pion does not get mass under Spontaneus breaking of chiral symmetry, but the quarks do?

Some sources state that when the mass of a quark goes to zero, it allows for Spontaneous Breaking of Chiral Symmetry and gets a constituent mass of about $200\, \mathrm{MeV}$. Other sources state ...
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1answer
624 views

Question about a nuclear bomb test photo

What are those white lines connecting the ground to the sky on the left side of this photo? I've see these before in the nuclear bomb test films too. They're apparently already in place upon ...
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3answers
2k views

Why is beta negative decay more common than beta positive?

In simple terms, why is beta negative decay more common than beta positive? I know it's something to do with occuring inside/outside the nucleus - but I can't find a simple, easy to understand ...
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1answer
91 views

Creation of Nuclear Isomers

As I understand it, if a nucleus is excited with energy exceeding its ground state, it releases energy via gamma radiation. An example would be technitium 99m, a medical tracer with a 6 hour half life ...
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89 views

Is it possible to create a nuclear reactor the size of a melon? [duplicate]

Possible Duplicate: What is the minimum amount of fissile mass required to acheive criticality? I want to make a red laser the only problem is that the power is not sufficient so I had to ...
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2answers
158 views

Synthesizing elements (Nuclear Physics/Alchemy?)

Based on my limited knowledge of nuclear physics, it seems that one day it may/will be possible to synthesize whatever elements we may need, given enough energy. Is this accurate? Is there a table ...
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1answer
391 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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4answers
3k views

Why are nuclear reactors dome/bell shaped?

Just what the title states. What is the reason that a Nuclear reactor has a characteristic dome/bell shape?
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2answers
1k views

Strong force, where is the seperation?

In class I got given a diagram like this: (albeit without the Electrostatic force line) However the teacher told us the nucleons are typically separated when the force is zero. So as the string ...
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What are nuclear isomers? What is isomeric energy?

Can someone explain nuclear isomers to me, and in particular what the energy involved is? I understand generally that we're talking about moving from a less to more stable configuration of nuclear ...
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6answers
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How do we know that C14 decay is exponential and not linear?

In my previous question I asked Please explain C14 half-life The OP mentioned that I was thinking of linear decay and C14 was measured in exponential decay. As I understand it, C14 is always in a ...
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0answers
458 views

Please explain C14 half-life [duplicate]

I understand that C14 decays at a given rate. I also interpret this to mean that 100% of the atoms of C14 in an object will all decay at the same right, individually. So if I have 4 C14 atoms, will ...
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1answer
171 views

Leaching of radiometric material, is it possible?

I've been doing some reading about radiometric dating and I've come across an interesting find. If anybody has any additional information on this, that would be great. First my question: In regards ...
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How reliable is Radiometric dating? Are there limitations? [closed]

Young earth creationists dismiss radiometric dating as unreliable, whats the truth?
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287 views

How does the internuclear repulsion vary in Hydrogenic atom collision?

Hydrogen fusion requires two hydrogen nuclei to get close enough (typically a few fm) to fuse. Much of the problem of creating a fusion reactor is overcoming the Coulomb repulsion between a pair of ...
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1answer
427 views

What are the average matter, antimatter, and binding energy composition of protons and neutrons?

For a free baryon at rest at room temperature, how much of its ~1Gev (rest) mass can (on average) be considered as matter, as antimatter, and as binding energy? For a baryon in a nucleus, I assume ...
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4answers
462 views

How do we know that the nucleus isn't a quark-gluon plasma?

The standard picture of the nucleus of atom is that is several distinct nucleons, which themselves are composed of quarks. However, it seems to me like a much simpler picture is that the nucleus is ...
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2answers
1k views

Effect of temperature on radioactivity?

I'm researching the effect of temperature on uranium radioactivity, however I can't find any solid empirical evidence to prove the notion that temperature does not affect radioactivity. Can anyone ...
13
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1answer
516 views

How come random matrices can predict energy spectra of heavy atoms?

Some of the applications of random matrices is to find the spectra of heavy atoms in nuclear physics which are usually difficult to find otherwise. How can starting from randomness of some kind, ...
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1answer
2k views

What is so special about iron?

I remember reading something about how iron was a highly stable element. Ever since then, I have looked at iron fry pans with new-found respect. However, in a recent discussion I was unable to ...