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

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Where does the $0.61$ come from in $ R \sin \theta = 0.61\lambda $?

In my A2 Physics textbook it says that In the estimation of the nuclear radius by using electron diffraction the equation $$ R \sin \theta = 0.61\lambda $$ where: $R$ = radius of the nucleus $\...
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30 views

How to calculate absorbed dosage

Lets say you have some unstable isotope which decays via beta decay. For example, lets say you want to calculate the amount of beta radiation that is emitted from the decay of $^{87}\textrm{Kr}\to ^{...
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750 views

What causes Potassium to decay into Argon the way it does

From evolutionwiki: "Potassium 40 decays into argon 40 through a process known as electron capture. In electron capture, an electron from the innermost electron shell "falls" into the nucleus, ...
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249 views

In the Iranian nuclear deal, how can IAEA detect nuclear activity after 24 days?

This is a question related to current events, but I want to ask about the physics, which are not explained in any news article that I can find. Ernest Moniz and John Kerry wrote an op-ed in the ...
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Have the BaF2 scintillators a strong correlation with the alimentation current that cause the shifting of the centroids in the distribution?

In gamma gamma correlation I suspect the presence of systematic error maybe caused by a non optimal alimentation voltage according to someone there is a quadratic correlation between centroids ...
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34 views

How is the amount of radiation calculated from a decay?

Lets say you have some unstable isotope which decays via beta decay. For example, lets say you want to calculate the amount of beta radiation that is emitted from the decay of $^{87}\textrm{Kr}\to ^{...
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13 views

Nuclear physics study materials

I'm currently a ChemE undergraduate student and wish to pursue masters in nuclear engineering. Can you suggest some introductory reading material so that I can get acquainted with nuclear engineering ...
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33 views

C-parity violation evidence

I know about the CP-violation experiments from the 60's and the P-violation from the 50's. But, is there a similar experiment which displays (perhaps historically in the same way as the experiements ...
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34 views

What would be radiated from exposed nuclear reactor core? [on hold]

Let's imagine a space beacon; a satellite with a nuclear reactor on board, built in such a way, that while control (cooling, fission level regulation) is maintained, a part of the reactor core is open ...
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36 views

propagation of error - sin^4

I am currently working on an analysis of a Rutherford scattering and encountered a somehow strange behaviour for the errors. It basically boils down to the behaviour of: $$\sin(\theta/2)^4$$ For ...
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52 views

Forbidden transition

My question concerns something I just read on wikipedia whilst looking up forbidden transitions, here: https://en.wikipedia.org/wiki/Forbidden_mechanism#Gamma_decay Specifically, this sentence: "...
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44 views

Derivation of Critical Mass of U-235

I am having trouble following an explanation of the critical mass of U-235 from my book (for high school physics). First off, every chain reaction of U-235 releases on average $\nu = 2.42$ neutrons. ...
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75 views

The counter-intuitive time scales in atomic physics and nuclear physics

Compare atomic physics and nuclear physics. The interaction in the latter is much stronger than that in the former. However, the typical spontaneous emission time scale in atomic physics is on the ...
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31 views

Model for obtaining the magnetic moment of a neutron [closed]

The anomalous magnetic moment of a neutron ($g_s=-3.83$) could be considered as a fixed proton ($g_s=5.58$) with an orbiting $\pi⁻$ meson in an $l=1$ state. a) What is the magnetic dipole moment of ...
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3k 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 ...
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3answers
971 views

Long time deviations from exponential decay in radioactivity

Are there any examples of common substances whose decay is not exponential? We're used to thinking about radioactivity in terms of half-lives. This is a concept that makes sense only for a decay that ...
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24 views

Meson production not originating from a collision

Does anyone know a process that produces mesons other than through collisions from particle accelerators and cosmic ray experiments? Thanks DaPhys
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2k views

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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1answer
375 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 ...
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2k views

Nuclear bomb power - myth?

I'm not experienced in physics yet (if it helps I've covered as much as acceleration, momentum and energy transfer/chemistry ionic and covalent bonding) but I've heard that the way people compare ...
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1answer
55 views

Gamma spectroscopy – What is this structure?

What is this strange structure in the gamma spectrum between 450 and 550 keV (below) around the peak at 477 keV? The spectrum seems to rise to a plateau (almost like a small Compton plateau) around ...
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51 views

Quantum tunneling and the Gamow Factor

I've seen the equation for the probability of particles overcoming the Coulomb Barrier in the following form: $$P(E)=\exp\left[-\sqrt{E_G/E}\right]$$ Where I'm using the numerator $E_G$ as the ...
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1answer
27 views

How can I determine the interaction knowing the decay formula?

I know the kind of interaction occurring in very common reaction. For example, I know that the interaction: $e^- + e^+ \longrightarrow \mu^+ + \mu^-$ is driven by the electromagnetic force (there is ...
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41 views

Can We “Tune” The Radiation Output Of a Nuclear Device.?

After reading "Project Orion", the 1950's plan to launch a large mass spaceship using small nuclear devices, (and also from common sense), I realise that a lot of nuclear research is classified. The ...
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2answers
111 views

How neutron can have an antiparticle since it have zero charge?

Antiparticles are defined as fundamental particles having the same mass but opposite charge. Now, a neutron has a particular mass (say m) , but zero charge ( =0). Its antiparticle should have mass=m ...
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111 views

Who determined the half-life of Uranium 235 and how?

By Wiki, the half-life of Uranium 235 is as long as 703,800,000 years. This is huge. Therefore, on an human time scale, the decay is very small. This should pose difficulty for determining the half-...
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What would happen if a hydrogen bomb were to explode in Saturn's atmosphere?

Purely hypothetical since any kind of testing in atmosphere/space is banned by international legislation/agreement. The humans have already bombed Luna so ... what could be expected to happen on ...
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159 views

Nuclear to Electricity Energy Conversion

Currently nuclear power generates heat, which heats water into steam that turns conventional turbines. The energy conversion is as follows: photonic->heat->kinetic->electric This would result in low ...
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3answers
9k views

Would being underwater help survive a nuclear bomb?

If I jump in my pool, on the river near my house knowing that a nuclear bomb, or atomic or H-Bomb exploded around 10 km from my house, would I survive? The way I see it is that water will protect me ...
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Why can't Iron fusion occur in stars?

It is said that iron fusion is endothermic and star can't sustain this kind of fusion (not until it goes supernova). However star is constantly releasing energy from fusion of elements like Hydrogen ...
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Is it possible that there are stars working on fission?

Most/all stars are getting their energy from fusion of small atoms like our sun. But is it possible according to the laws of physics that there are stars getting their energy from fission fe with ...
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34 views

Total Angular Momentum of Hadrons

Hadrons are made of 2 or 3 quarks. Quarks have spin 1/2, so Mesons can have spin S = 1 or spin S = 0, and Baryons can have spin S = 3/2 or spin S = 1/2. Is there orbital angular momentum of the quarks ...
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43 views

Effect of a nuclear weapon on the Moon

In some science fiction novel, there is the scenario of using nuclear weapons to deflect an Earth-approaching asteroid. But the question is, is a nuclear weapon really as useful on the moon or an ...
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14 views

Gamma decay multipolar transition rate?

I have been trying to derive the equation for the transition probability per unit time/transition rate for gamma decay of a nucleus, as given by equation (21) of this article. I have also gone through ...
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76 views

What is the BG Equation?

About 45 years ago or so I was a Physics department staff computer programmer when I was a physics major undergrad. I worked with a professor doing research on nuclear shell models -- he was ...
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20 views

What is $\beta^-n$ decay?

I'm looking on the nndc chart of nuclides and am seeing $\beta^-n$. What is this? http://www.nndc.bnl.gov/chart/reCenter.jsp?z=3&n=6
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16 views

Is the decay of nuclei also depending on the 'age' of nuclei or whether they are created or not? [duplicate]

Usually the decay is said to be randomly but the average period of decay of certain atoms are stable. So if you randomly take a bunch of the same atoms the average time before the decay will fe be 5 ...
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11 views

Assumptions that led to Wigner surmise of nuclear level spacings

In 1957, Wigner surmised (guessed) that the probability density of the spacing between adjacent energy levels of complex nuclei is given by $$ P(s) = \frac{\pi}{2}s e^{\frac{-\pi s^2}{4}} $$ This is ...
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1answer
23 views

Dependence of atomic mass number in the Bragg Kleeman rule

I have just staring learning about radioactivity, more or less about alpha particles and how there range can be approximated by the Bragg Kleeman rule, $\displaystyle{R \varpropto \frac{\sqrt{A}}{\rho}...
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24 views

Gamma spectroscopy - Nuclide identification

I have a question about what the usual practice is for nuclide identification in gamma spectroscopy. For example, if I see a line at 477 keV, I would write that the origin of this line is $^7Be$. As ...
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1answer
7k views

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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1answer
39 views

What is the interrelationship among PD, T1 and T2 in relation to MRI

Proton Density (PD), Spin - Lattice Relaxation Time (T1), Spin - Spin Relaxation Time (T2) are three major characteristics by which we can distinguish different types of tissues and all three are ...
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Tunneling of alpha particles

Consider this explanation of the alpha decay: It says The Coulomb barrier faced by an alpha particle with this energy is about 26 MeV, so by classical physics it cannot escape at all. ...
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1answer
41 views

Nuclear Energy Depletion in Solar System [closed]

Lets keep this simple. Lets assume that the amount of known fissionable material is fixed. Lets assume that energy demand is the same for 2015, from now until depletion, to keep it simpler. How long ...
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225 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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Determining thickness of Aluminium foil with alpha particles

So I'm trying to derive an equation to determine the thickness of a thin aluminium foil using Bragg Kleeman rule. I've so far got that the range of the alpha particles in aluminium is $R(Al)=R(air)\...
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1answer
32 views

Predicting a decay chain? [duplicate]

Is there a way to predict a decay chain? Let's say I have U-238 and want to find out its decay chain, is there a way to do that without looking it up? Thanks in advance.
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56 views

What happens when fast moving electrons hit hydrogen molecules?

Just like the creation of X-rays. Where fast moving electrons are bombarded on some Heavy element. What happens if the we keep compressed Hydrogen instead of the heavy metals? Surely it will form ...
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700 views

Why are atomic quadrupole moments calculated using nuclear spin?

It's my understanding that electric quadrupoles interact with the gradient of an electric field, and I understand roughly how this works. I am trying to calculate the interaction between an atomic ...
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1answer
122 views

Physics needed for a quite well understanding of nuclear bomb [closed]

I am an undergraduate student in physics and mathematics and one of my early dreams in physics was to understand the way nuclear weapons work. Is there a book which deals with the physics and the ...