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

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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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217 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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132 views

Radioactive decay / binding energies

If my understanding is correct, the binding energy determines a nucleus' stability and the greater the binding energy, the more stable the nucleus (e.g iron-56). The mass of the sum of nucleons that ...
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534 views

Would a matter-antimatter explosion cause fallout?

I know matter and antimatter annihilation release a lot of gamma rays which are considered ionizing radiation if I am not mistaken. But what if the explosion happened on the surface of the earth, ...
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57 views

Reaction of Pu-239 to gradual increase of pressure

The question "Did NASA nuke Jupiter?" while debunked immediately (non-fissile isotope was used) arose many what-if questions. What would happen if a subcritical chunk of a fissile isotope, like ...
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47 views

Why did Otto Hahn use neutrons to generate transuranium?

In physics textbooks with chapters about nuclear fission there is often a historical introduction about Otto Hahn. That he tried to generate transuranium but discovered the nuclear fission. If you ...
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262 views

Is man-made Carbon Fusion possible?

In a type Ia Supernova, the carbon accumulated in the earlier stages of a stars death fissues to create even heavier elements. Could this be used by humans aswell? Is it theoretically possible to ...
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372 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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89 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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255 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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511 views

Iodine isotope question

Quick question for the nuclear engineers/physicists out there Where does I-134 come from? I cant find it in any of the charts of standard decay products of Uranium fission, but there is tons of the ...
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How do alpha and beta particles ionise surrounding particles?

I've been wondering about this question for a while. If you have alpha and beta particles released from a radioactive core, how do they ionise surrounding particles?
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Binding energy in fission

In nuclear fission the total rest mass of the products is less than the mass of the original nucleus. But on the other hand, the binding energy of the products is higher. Doesn't the decrease of the ...
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Angular momenta of photon

$A^\mu$ can have multipole expansions in classical electrodynamics. This gives rise to dipole photon, quadrupole photon etc. For dipole photon $j=1$ (In electrodynamics books they write it as $l=1$). ...
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51 views

What is the chemical symbol for Mu-mesic atoms?

Is there a convention for chemical symbols of mu-mesic atoms, at least for ones bound to light atomic nuclei?
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181 views

What is the speed of a neutral pion and how is it measured?

Alvager et al 1964 purportedly disproved Ritz's emitter theory in an experiment that generated neutral pions with a vellocity of $v =B.c$ where B is slightly smaller than one. How is the velocity of ...
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74 views

Confusions relating mass defect

I think I am confused between the mass defect of just splitting up a nucleus into its component nucleons and the mass defect involved between the two sides of a nuclear transmutation reaction. I ...
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674 views

In nuclear fusion reaction, what is the percentage of mass converted to energy?

I read somewhere that it is about one percent of the mass, but I find this too high. Also I have done some calculations, for example, the Tsar Bomba was 50 MT bomb and weighed about 27 tons. Although ...
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100 views

One body harmonic oscillator states expressed in terms of creation operators

I am reading trough chapter one of Moshinsky's "The harmonic Oscillator in Modern Physics". However i am having some trouble with the mathematics in section 8 of chapter 1. I will sketch a summary of ...
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136 views

Ground states in the shell model for odd-even nuclei

I understand that even-even nuclei (Z and N number) have zero spin because of pairing. Even-odd nuclei have the spin of the odd nucleon, and parity is given by $(-1)^L$ - so my question is, ...
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186 views

Spin and Parity of $^{17}_8 O$ excited states

$^{17}_8 O$ quoted here has a spin of 5/2 and parity of +1 for the ground state, I agree with this, the unpaired neutron is in the $1d_{1/2}$ state so l = 2, spin = 5/2. Now I want to figure out the ...
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125 views

Alpha-stable isotopes

Why some isotopes with positive alpha-decay energy are stable? For example, alpha-decay energy of stable 194Pt is about 1.5 MeV. But there is no stable isotopes with positive beta-decay energy. ...
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85 views

Can raw fissile/fusile minerals be triggered by seismic activity?

Wikipedia indicates the approximate energy released by an earthquake relative to the destructive power of TNT With reasonably large quakes (> 4.0 on the Richter Scale), the energy dissipated is of the ...
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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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If there is a meltdown at the Fukushima reactors, would the control rods melt also?

According to the reports, the shutdown procedures at all the Fukushima reactors were successful, and all the control rods were fully inserted. So - if there was a meltdown, would the control rods ...
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Proton as superposition of hadrons: $\vert p\rangle = c_0\vert p_0\rangle+c_1\vert h\rangle+\cdots$

I have a question regarding hadron fluctuations. For instance on page 85 in Feynman's "Photon-Hadron Interactions" equation 15.2 reads: $$\tag1\vert \omega\rangle = \vert ...
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physical intuition behind quasi-bound state formation in feshbach resonance

In Feshbach resonance, by scattering theory formalism it is found that the resonance in cross-section happens when bound state energy of the closed channel is near to the scattering state energy of ...
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how is feshbach resonance potential term physically produced?

In Feshbach resonance model, a 2*2 potential term with space dependent diagonal and non-diagonal terms is written $\left(\begin{array}{cc} V_{11}(\mathbf{r}) & V_{12}(\mathbf{r})\\ ...
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69 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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Unknown peaks on RBS spectrum

I was given a sample, that it is supposed to be a medium thickness Rhodium on top of an infinite silicon waffer. The experimental RBS spectrum along with the simulation looks like that Apparently, ...
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How to describe hadron-hadron strong interactions from QCD?

I'm trying to set up the problem of deriving the thermodynamics of hadronic matter. I know how to proceed in the case of an effective description such as mean field (Walecka/linear sigma model) but ...
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118 views

Fusion vs. Fission

I understand why fission generates large amounts of energy when the nucleus is split, but then why does fusion generate such large amounts of energy. If fission releases energy when some mass is lost ...
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970 views

Decay of Cobalt-60 isotope

How does the Gamma decay of Cobalt-60 occur? Motivation: A research team led by D. Habs made contributions to our understanding of the gamma decay of Ca-40 and Zr-90: ...
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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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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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229 views

Is it viable to convert nuclear waste into safe isotopes?

I read that powerful pulsed lasers can change isotopes: J. Magill, et. al.: "Laser transmutation of iodine-129". Did anyone estimate what would be the energy costs to transmutate 1 kg of fission ...
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233 views

Neutron decay and electron anti neutrino $n\to p + e + \bar{\nu}_e$

Why do we need neutrino to explain neutron decay? Is there any evidence regarding existence neutrinos in the context of $n\to p + e + \bar{\nu}_e$?
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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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54 views

Transmutation with cosmic radiation possible?

Can cosmic radiation (alpha radiation) transmute the material of a space craft, particular carbon, titanium and aluminum? Where can i find transmutation tables or formulas to calculate the ...
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110 views

Is $E=mc^2$ reserved to nuclear physics?

I was wondering, while putting a log in my fireplace, how much energy the piece of wood would give. The most famous formula poped into my head: $E=m \cdot c ^ 2$! Is this formula applicable to a ...
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Why are breeder reactors not more prevalent? [closed]

I recently learned about breeder reactors, which are able to create more fissile material than they consume. They seem to be superior to the types of nuclear reactors currently in use. What are the ...
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264 views

Simple PDE as a theory of everything?

For the sake of simplicity, I’d like to believe that there is one master non-linear partial differential equation governing physics. In particular, consider a Klein-Gordon form: $$ \frac{\partial^2 ...
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461 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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56 views

Temperature Dependence of Fission

I've always heard fusion depends on incredible temperatures and pressures, but I'm curious what the temperature dependence of fission is. For instance, if I had uranium and heated it to a ...
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145 views

Does the fact that protons and neutrons have larger mass than electrons mean they're bigger in size?

and so if a proton is so larger than an electron doesn't that mean it has a shape? What would be the shape of a subatomic particle? are they spherical?
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Could there be a correlation between the Island of Stability and dark matter?

I can only boast of my passion for science and not of any credentials. I ask because I am curious, and it is not the type of question one can easily Google! What if the key to discovering and ...
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557 views

Can antimatter be used as fuel for nuclear reactors?

I completely understand the difficulties of making and storing antimatter, so I am not talking about the mechanism or the way of doing it here, I am just talking about the concept. As far as I know, ...
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479 views

Under what conditions is a pure fusion nuclear bomb possible?

Is it possible to build a pure fusion and powerful nuclear bomb? (because due to the harsh conditions of enriched uranium, I would guess most of today's world countries will want to build pure fusion ...
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Was the early Earth radioactive?

I've been reading of the (surprising) fact we are uncertain on whether there is nuclear fission in the center of the Earth or not (yet we know so much detail on structures at the other end of the ...
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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 ...