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

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Radioactive decay-Why does it depend on numbers left

As textbooks describe the rate law for radioactive decay as a first order reaction dN/dt=kN,why is it so(mine does not give the reason)? How is the radioactive decay of one atom depeendent on the ...
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Why does the alpha particle not excite the isovector transitions in nuclei?

The $\alpha$ particle is a very commonly used projectile for studying inelastic scattering. It has T=0 ans S=0. But it only excites the isoscalar vibration modes in target nuclei, and not isovector ...
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132 views

How does the discrete energies of alpha and gamma rays prove the existence of nuclear energy levels

I was reading up about Nuclear Energy Levels and came up with the aforementioned question. To me, there seems to be no direct connection between the two statements and therefore, I would like to know ...
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Question on matter waves

So,I just started this topic on modern physics in school that contained the concept of"de broglie waves" or "matter waves" and there are a few concepts that are unclear to me. Firstly, does a single ...
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20 views

Using ion radiation to make electricity? [duplicate]

Is it possible to capture the ion radiation from a nuclear source and make electricity from it? I always thought it was possible, but never looked into it? Is this what a beta voltaic battery does?
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Protonic emissions

In a beta emission a neutron decays,into a proton and an electron, and an electron randomly gets ejected from the nucleus due to the phenomenon of barrier tunnelling(correct me if am wrong).But why is ...
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40 views

Nuclear resonance and Breit Wigner Single level formula

I have been trying to understand Briet Wigner Single level formula and its implication. However, what is nuclear resonance in terms of nuclear cross section ? Is it just the sharp increase in nuclear ...
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124 views

time-dependent Hartree-Fock for two-component bosons

How does the ansatz for the time-dependent Hartree-Fock wavefunction look like in the second quantization if we have two-component boson system and in one case the Hamiltonian commutes with number of ...
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17 views

CDCC method for break-up cross sections

Is anyone familiar with the Continuum Discretized coupled channels method commonly used to compute breakup cross section of weakly bound projectiles? Some authors talk about including target ...
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33 views

Is an “underwater” submarine affected by a nuclear bomb exploding above the water? [duplicate]

I've just read Would being underwater help survive a nuclear bomb?. Submarines are way more armored and far from the surface than a human body (https://en.wikipedia.org/wiki/Submarine_depth_ratings), ...
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44 views

Does Rydberg's formula work for different orbitals?

Rydberg's formula is given as $\frac { 1 }{ \lambda } =R\left( \frac { 1 }{ { { n }_{ 1 }^{ 2 } } } -\frac { 1 }{ { { n }_{ 2 }^{ 2 } } } \right) $ where ${ n }_{ 2 }$ and ${ n }_{ 1 }$ are the ...
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How is an electron “recycled” in a neutron?

A proton is made up, they say, by 2 up and 1 down quark, drowned in a sea of virual paricles: when an electron is captured this process thereby changes a nuclear proton to a neutron and ...
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isoscalr or isovector modes of vibration in nuclei?

How can it be determined whether one incoming nucleus (say projectile) would excite the isoscalar modes of vibration in the target nucleus or the isovector ones?
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Question about calculating age of a uranium and lead containing object, based on the ratio of uranium-to-lead

I realize this is probably going to sound so stupid, but... here goes: Radioactive decay: We know that we can calculate the age of a uranium containing object by the uranium-to-lead ratio, due to ...
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1answer
29 views

Collectivity in nuclei

Why do inelastic scattering of nuclei as well as their electric multipole radiative transition (via say Coulomb excitation) show similar collective enhancement, even though electromagnetic field ...
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31 views

Cloud chamber and observations [closed]

What are the best ways to use a cloud chamber to study particles. What would you gain from observations done in a cloud chamber.
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75 views

Why is there only alpha and beta (and gamma) decay?

Why is it that we mostly speak of alpha and beta decay (when looking at emitted particles with rest mass)? Why don't we speak of decays that emit something like $2n3p$, $3n2p$ and so on? Do they occur ...
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48 views

Random Phase approximation (RPA) in nuclear physics [closed]

What does RPA mean? What makes it significant to be used to determine nuclear transition strengths and how?
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1answer
53 views

Nuclear fusion will consume all our hydrogen in some centuries?

First, sorry for bad English. If the fusion become a viable energy source, and used extensively, it will have impact on the amount of hydrogen in our environment? Unlike pollution by carbon dioxide, ...
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38 views

What would keep a hypothetical fusion reactor from “igniting the atmosphere”? [duplicate]

So in the early days of Nuclear fission, there was a concern about the resulting energy igniting the atmosphere in a ball of fire and world-wide death which is awesome terrifying awesomely terrifying. ...
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Control rods in RBMK - what is the difference between control rods which are inserted from above or below?

So, in Wikipedia it says the following: "Most of the reactor control rods are inserted from above; 24 shortened rods are inserted from below and are used to augment the axial power distribution ...
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42 views

Can electron capture occur with an external electron?

Can electron capture proceed with an electron not bound to the nucleus which decays (that is one that is bound to a neighboring atom, bound in a collective state like a conduction band, or free)?
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38 views

Grazing angle in a nuclear collision

How is the grazing angle calculated theoretically? Also, experimentally, the quarter point angle of elastic scattering angular distribution is taken as the grazing angle in accordance with ...
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32 views

What is the physics behind distorted wave Born approximation?

If distorted wave Born approximation is used to account for nuclear couplings, then does that signify that nuclear couplings are only upto the first order?
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1kg mass impacting at half light speed - effects?

Such a mass would have kinetic energy approximating a 1 mega-tonne thermonuclear weapon. So, what would such an object do if it hit the Earth? We know how destructive such an energy release can be, ...
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To which extent is the treatment of nuclear multipole radiation by the means of a classical electromagnetic field valid?

In the treatment of nuclear multipole radiation, for example in the context of nuclear gamma decay, it is standard, at least at the elementary level, to formalize the electromagnetic radiation as a ...
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36 views

Can the probability of electron capture in a metal hydride be increased by extreme electric current?

An example of a metal that can hold a lot of hydrogen is palladium. The hydrogen atoms (protons) in the metal lattice are positive and the electrons are negative. When a large electric potential is ...
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Nuclear bound states

"The $3/2$$^-$ ground state of gallium-61, Ga-61, is bound by only $190$ keV relative to the system: Zn-60 + p, where p is a proton. There are excited Ga-61 states at $271$ keV and $1000$ keV" How do ...
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Calculating released energy of a fission reaction

I have a question regarding the power of a fission reaction: You have a Uranium U235 atom, in which you send a neutron at to cause it to split into two (or more?) new cores. This reaction also sends ...
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Cause for spikes in trinity bomb test

In Richard Rhodes' book, The Making of the Atomic Bomb, I was reading about the Trinity nuclear test. High speed photos were taken and this one is from <1ms after the detonation. The book mentions ...
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256 views

Why is a stellarator-type nuclear fusion reactor so oddly-shaped?

My first impression: It's a mess. Why is it shaped like that? I can't find any info about its shape other than it's a special arrangement of magnetic coils. (link) Here's some more images of it on ...
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Fermi's theory of beta decay - Does Fermi's Hamiltonian have the wrong transformation properties?

I'm studying the theory of beta decays as proposed by Fermi in the 30's, and I found an inconsistency between the transformation properties that he claims for his Hamiltonian and the transformation ...
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39 views

Energy from Uranium fission

How do I find the energy released by uranium fission into Nb and Pr ? Every time I see the equation for some nuclear fission it always just states the energy released but what if we didn't know it as ...
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71 views

What would happen if I gathered stellar sized masses of iron?

Lets say I had a bag that when turned upside would start pouring out iron shavings and never ever stop. Viola, there's my infinite source of iron. Now, lets say I just continued to dump this iron ...
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84 views

Nuclear fission plant loss of coolant accident (LOCA): how bad could it get?

In 1979 the world experienced its first severe nuclear plant accident at Three Miles Island, when TMI-2 underwent a LOCA with devastating consequences for the reactor core. About 50 % of it melted and ...
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How can I read the rotational bands of nuclei from nuclear data sheets?

Recently I have been reading about collective excitations in nuclei and how in deformed nuclei rotational bands are formed due to an electric quadrupole moment. Given this I was wondering how I can ...
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Sustained nuclear criticality in liquid vortex

In 1958, chemical operator Cecil Kelley was killed by a nuclear excursion in a mixing tank. A tank intended to reprocess trace amounts of dissolved plutonium-239 accidentally had dramatically more ...
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Why is Iron the most stable element? [duplicate]

Iron has the highest binding energy per nucleon in the entirety of the known elements. But why Iron specifically? What makes it have the highest binding energy per nucleon?
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Cesium-137 From Fukushima Meltdown

I've been reading up on the Fukushima nuclear meltdown and its effects it had on the environment. The iodine-131 initially released from the incident decayed after 8 days, but other isotopes such as ...
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If there are long-lived elements in the Island of stability, why are they not present in Nature?

To my understanding, some (but not many) physicists speculate that the Island of stability may contain long-lived elements, as in a billion or so years. But couldn't we rule that out just by the ...
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Coulomb excitation of a heavy nucleus

In Coulomb excitation measurements involving a stationary target getting excited, why do the de-excitation $\gamma$-rays get Doppler shifted and Doppler broadened as well? How can these be corrected ...
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Is Blatt-Weisskopf's treatment of nuclear forces still relevant today?

As in the title, is the treatment of nuclear forces by Blatt and Weisskopf, as in Chapter III of "Theoretical Nuclear Physics", still relevant today, especially with regard to the role of exchange ...
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Why is $(N,N' G)$ reaction not listed?

If I go here, http://www.nndc.bnl.gov/ensdf/# go to the by Nuclide tab, check the "Reaction" box, and search for $\rm^{24}Mg$ in the Nuclide box; various reactions which produce $\rm^{24}Mg$ appear....
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82 views

Mass of proton vs mass of nucleus

I have just started reading nuclear physics.I know that the sum of masses of the quarks is less than the proton or neutron itself as a whole . But why is it that the sum of the masses of the nucleons(...
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Safety of Polonium Isotope source

I saw a YouTube video by a guy demonstrating Geiger Counter use and one of his radioactive test sources was a disk with Polonium. He casually mentioned that this was the poison used to kill that ...
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Nuclear accident near Uranium mine

What if someone, without knowing, detonates a very small nuclear bomb underground within a rich mine (rich on Uranium but not enriched type) that has ~500 tons scattered to 1km³. Would the neutron ...
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51 views

Are the leptons in $\beta^-$ decay already present in the nucleus in some form?

In beta minus decay, beta-minus particle and anti-neutrino are ejected, leaving behind daughter nucleus. $\beta^-$ and anti-neutrino both are leptons. Were the leptons already present in the ...
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64 views

Isoscalar and isovector terms in optical model potential

How does one obtain the isoscalar and isovector terms of the nucleus-nucleus interaction potential and what do they signify?
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Probability of nuclear decay of small staring number of atoms

I came across a rather dubious question that a teacher had put in a power point. It said something like,"Given a sample of 100 atoms of isotope x, after one half life of the said isotope, how many ...
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76 views

Fission bomb: How much of it burns?

I am wondering about measured data on how efficient fission bombs were say the first ones. Since the fission in chain reaction releases large amounts of energy in fractions of a second, I imagine ...