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

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Trigger supernova artificially

Is there a way to artificially trigger a given star to be supernova? Anyway? I would appreciate fast ways. For instance, preference will be given for ways that doesn't take few billion years to ...
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Why did “tickling the dragons tail” by Louis Slotin not cause an explosion?

I have been reading the excellent Command and Control by Eric Schlosser and discovered more about Louis Slotin's experiment with "tickling the dragons tail" and the infamous Demon Core. What I don't ...
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The Form Factor in Nuclear physics

We know $$F(\vec{q})=\int e^{i\vec{q}.\vec{r}} \rho(r^\prime) dv^\prime$$ where $\vec{q}$ is the momentum change of scattering electron. But what is the physical meaning of it ?!
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Identification of massless, chargeless $x$ in a nuclear reaction

On Friday, we had our Physics test. We (the tenth grade students) have the basic introduction to Radioactivity and a few nuclear reactions in our syllabus. In the test, the following question was ...
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How do scientists estimate elemental-abundance in the universe?

I understand how cosmological observations can estimate the amount of 'baryonic matter' in the universe, but what I don't understand is how scientists can estimate the abundance of a particular ...
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What does the exponential decay constant depend on?

We know the law of radioactivity: $$N=N_0e^{-\lambda t}$$ where $\lambda$ is the exponential decay constant. My question is: This constant depends of what?
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Is an atom charged after undergoing beta emission?

After beta emission, an atom's mass number remains the same while the number of protons increases by one. As far as I know, the beta particle (electron) is too energetic to be recaptured. If this is ...
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Ambiguity in ordering of isospin states for Clebsch-Gordan coefficients

In studying isospin for nuclear physics, I am confused a bit by an ambiguity I found. If a process that goes from $K^- + p \rightarrow \Sigma^0+ \pi^0$, I can write the isospin for the left hand side ...
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24 views

Why are the dineutron and diproton unbound?

It is known that there is no diproton and dineutron nuclei. Does this mean that two protons or neutrons are not actually attracted to each other? Even if the attraction was weak, wouldn't it cause ...
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Isospin quantum number for light nuclei

Does anyone know where I can find the Isospin values for light nuclei (H, C,N, O, S, Cl, ..) in their ground state?
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28 views

$\beta^+$ decay question

I read that all baryons apart from the proton itself decay into protons (why though?) and that mesons do not decay into protons due to having less mass than protons. Thus it makes sense for the ...
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Detecting radioactive material at a distance

I have heard a lot about the failures of even the best-funded anti-ballistic missile technology. The usual explanation is that ABM is very hard after the boost phase because of evasion techniques and ...
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Why build nuclear reactors on shorelines?

While not directly a physics question, I can't think of forum better capable of answering my question. In discussions over Japan's nuclear reactor situation the observation was made that reactors ...
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32 views

Is chain reaction possible in stable isotopes?

Is nuclear chain reaction possible in isotope that is considered stable? Are there examples?
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How doesn't an ionization chamber leak?

I'm sure my understanding of an ionization chamber is incorrect, so please point out the error. Suppose we are using an sealed ionization chamber to detect the energies (trajectories) of a particular ...
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Starting a nuclear reaction

In Chemistry, an amount of energy has to be supplied for a reaction to occur. This energy, known as the "activation energy", breaks up the bonds between molecues in the substance. It is equivalent to ...
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nuclear physics- Energetics and Mechanics of Nuclear Reaction Homework

A sample of $^{24}_{12}\mathrm{Mg}$ is bombarded by a monoenergetic proton. If the resulting nucleus in a $^{24}_{12}\mathrm{Mg}(p,\gamma)$ reaction; $^{24}_{12}\mathrm{Mg}(p,\gamma)$ has its ...
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Alpha decay radioactivity [closed]

Do electrons actually escape from a radioactive element ? Or simply the helium nuclei that ? what actually is the structure of a fully decayed radioactive element ?
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42 views

How to calculate scalar neutron flux

I am really confused about the difference between flux and scalar flux. I have a specific question: If we have a parallel neutron beam of strength $\phi_0$ given in neutrons/cm$^2$s, incident on a ...
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59 views

Chemical potential for nucleons

Do you know if the concept of chemical potential can be properly defined for nucleons in the nuclei? I mean, if I can picture the nuclei like an interacting gas of nucleons, then may I think of a ...
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43 views

Could someone explain the “revolving frame” to me, as it is used in basic NMR?

I am an undergrad intern at a national lab currently working with a basic proton NMR device. The device consists of two big coils which provide the static magnetic field, and a smaller coil, which ...
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Is it really possible to create some mass only from equivalent energy? [duplicate]

From Special theory of relativity we know that $E=m_0 c^2$, which says about mass energy equivalency. But my question : **Is there any real experiment where some mass is created purely from energy? ...
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Copper coils for nMRI

Given the lack of financial efficacy in the medical industry, I was wondering if nuclear magnetic resonance imaging would be possible with a copper/silver coil if the use is short 10 second imaging ...
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38 views

Calculating $\alpha$-Particles Detected During Rutherford Scattering (Cross Sections)

I am currently studying nuclear cross sections and this question considers the classic Rutherford scattering experiment. Here is a diagram of the experiment: The detector is at right-angles to the ...
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Why does an atom remain uncharged after emission of an alpha particle?

When an alpha particle is emitted, two protons and two neutrons leave the nucleus but the electrons remain the same in number. Why does the atom remain uncharged although it appears it should have a ...
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How much iron would I have to shoot into the sun to blow it up?

My understanding--though it's from a Science Channel show so I'm not sure if it is correct--is that there is a fusion reaction happening in the center of the sun. Atomic nuclei are being created and ...
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What's the largest mushroom cloud possible from a coffee cup/grenade sized nuclear bomb?

Assuming the coffee cup is $16$oz = $1$lb = $0.4536$kg or $ \sim 450$mL I did a quick comparison to the W54 assuming there was a linear ratio (wishful thinking perhaps), and got it to be around 8m ...
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Can the half-life of rubidium 87 be theoretically estimated?

Can the Fermi golden rule be applied to give an approximation of this half-life?
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Incoherent assumption of the parton model

Consider the scattering process $ep\rightarrow eX$, in the frame of an ultra-relativistic electron, the partons inside the proton are "frozen," and since the time scale of strong interaction is much ...
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In the earth's crust, why is there far more uranium than gold?

In parts per million in the Earth's crust Uranium is around 1.8ppm and Gold 0.003ppm. Given that it takes far more energy to create Uranium than Gold, why is this?
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Nuclear Spin of Sodium 23

I am actually calculating the nuclear spin of Sodium 23. Here we have 11 protons and 12 neutrons. Now both the nuclei are short of the magic numbers. When I use the shell model for protons and ...
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Questions on beta-decay

According to my textbook, for all the beta decays, it is required that the mass of the original atom to be heavier than the mass of the final atom. Is this due to the fact that all the beta decays ...
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Are we close enough to objects?

Are we able to touch the atomic orbital of an element ? If so, wouldn't there be a current flowing ? If not, then where do we actually touch when we hold it ?
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How do control rods work?

I understand the basic idea of nuclear fission: put a bunch of fissionable material together and let the neutrons fly. An atom gets split, kicking out a few more neutrons, which split other atoms, ...
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The role of W bosons in the weak nuclear force and beta decay

I am a beginner Physics student and I am studying the weak nuclear force and how particle interactions work. Now, from my book and the Feynman diagram, I learned that a neutron can change into a ...
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Blazars and nuclear physics!

How are studies on blazars related to the field of nuclear physics? Should these not purely belong to Astrophysics? Just inquisitive.
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Age of the Earth and the star that preceded the Sun

One of the great unheralded advances made in the history of science was the ability to determine the age of Earth based on the decay of isotopic uranium. Based on the apparent abundance of uranium in ...
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Nuclear fusion and the Sun [closed]

I am working on a science project on the Sun. I have found that in order for nuclear fusion to work, it needs both helium 3 and 4. Why can't nuclear fusion be done with just helium 4? How can we ...
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Online physics lecture [closed]

I'm looking for online courses "video" for Classical electrodynamics and nuclear physics for undergraduate students .. do you know where I can find it ?
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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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108 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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Which nucleus is the most resilient against gamma-induced fission?

To state the title question perhaps more precisely: What is the largest photon energy $E_{\gamma}$ and the corresponding mass number $A$ and atomic number $Z$ of a suitable nucleus ${}^A_ZX$ ...
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Can the High beta fusion reactor work?

Are the claims made about the http://en.wikipedia.org/wiki/High_beta_fusion_reactor realistic? Can such a small fusion reactor really work?
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Places where fluid dynamical ideas show up in physics? [closed]

One common theme of physics is that ideas and models developed to describe one type of physical situation are found to be nicely applicable to another type of situation. I know that fluid mechanics, ...
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Integration & bremsstrahlung calculation

In this paper (relevant pdf section) that I'm reading, involving the calculation of bremsstrahlung in electron proton scattering (diagram below), the author calculates the integral over outgoing ...
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Why is an electron negatively charged, and what is the difference between negative and positive charges?

Nobody has yet defined the actual meaning of a charge, or why a negative charge is different from a positive charge. Everybody knows that positive charge is due to protons and negative charge is due ...
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Can we observe proton decay?

I know that the half life of a proton is more than $6.6\cdot 10^{33}$ years (antimuon decay). I have found this data on Wikipedia proton decay but I do not know the probability distribution that leads ...
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Why does nuclear waste have to be stored until the constituent elements decay naturally?

Fair warning, I have a bachelors in CS and have chemistry 211/212 under my belt. My understanding of the atom consists of a proton, neutron, and electron quasi-orbiting it in some sort of strange ...
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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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Near field and Nuclear magnetic resonance (NMR)

Why does Nuclear Magnetic Resonance (NMR) physics not concern itself with near field physics? All resonance wavelengths in NMR are much larger than bough sample, pick-up coil and excitation coil. ...