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

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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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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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31 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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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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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 $\rm^{24}Mg$ ...
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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 ...
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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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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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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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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 ...
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Is the transition electric quadrupole or magnetic dipole?

If a nucleus makes a transition from 0$^+$ ground state to 2$^+$ excited state, then will the transtion have E2 character, or M1? Or partly, both? Should the matrix elements of both E2 and M1 be ...
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Why do products of nuclear decay have a lower mass than the original nucleus, when the sum of the mass of its nucleons is larger? [duplicate]

I've just started covering the topic of binding energy in Year 13 at school (final year before University). The definition we've been given of binding energy is that it is the work done when ...
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How is the temperature of a star related to gravity?

As far as I know the Sun gets its energy from the fusion reaction, where Hydrogen is converted into Helium. I was watching an episode of Cosmos: A spacetime odyssey. There Neil deGrasse Tyson said, ...
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Assigning values of angular momentum transfer

How do the shapes of the experimentally measured differential scattering or transfer cross sections help in assigning reliable angular momentum transfer values?
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Conceptual doubts regarding the Emission Spectrum

I was reading up on the emission spectra and the author of my textbook states that If you expose a container of gas at low pressure to a strong electric field, light is emitted from the gas. ...
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Harvesting energy from hot, radioactive fuel from nuclear reactors

I have a couple of questions about nuclear reactors used for electricity generation. a) If the spent fuel is still radioactive and quite hot, why is it disposed off ? Why can't its energy be used / ...
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Model of the nucleus as fermi gas

I am taking an introductory course in modern physics, and am reviewing some of the exams from previous years. In our course, we studies the Fermi gas model for electrons in a metal. In one of the ...
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How is the interaction radius of fusion reactants determined?

To calculate the Coulomb barrier between two fusion reactants, the interaction radius (also called the fusion radius), r, must be known. How do I find the interaction radii of different nuclei?
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Condition for the perfect triaxial body [closed]

Why do a nucleus (body) having asymmetry parameter gamma=30 degree called as perfect triaxial nucleus?
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Are Geiger counters isotope-specific?

I was talking with an employee at a company that does I-131 therapy for hyperthyroidism and they said that the Geiger counters they use are "tuned" for I-131, implying that regular Geiger counters are ...
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Conceptual doubt regarding Nuclear Energy Levels

I was recently studying about nuclear energy levels and frankly, I thought that I understood the concept pretty well. However, this little problem showed me how wrong I was. The problem is given ...
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Is it possible for oxygen in the ocean to undergo nuclear fusion?

Could the oxygen in the ocean undergo oxygen burning (uncontrolled self-sustained fusion) if struck by a very large meteor or exposed to a similarly devastating cosmic catastrophe? Is it possible for ...
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Prompt gamma emission vs gamma decay

I understand prompt gamma emission to mean gamma emission in a time period shorter than a second. I understand gamma decay to be the relaxion of a nucleus into a lower energy level by emission of a ...
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Why is a nearby nucleus required for Pair Creation?

I was recently studying Pair Production and Annihilation. The author mentions that a nearby nucleus is required when the photon materialises into a particle and an anti-particle. The explanation given ...
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Probability of $\alpha$-decay

In standard Gamow model we assume that $\alpha$ particle is already in the nucleus, i.e. four nucleons are "glued" together and this particle is emitted. So, we assume that the probability of the ...
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What happens to covalent bonds after the nuclear transmutation of an atom in a molecule?

What happens when we have a decaying atom in a molecule, which has covalent bonds with other atoms? I assume some of the bonds will cease to exists, but I did not manage to find any rule about which ...
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Beta decay of radiocarbon

I read some weird equation on wikipedia about the beta decay of radiocarbon: ${^{14}_{6}C} \rightarrow {^{14}_{7}N} + e^{-} + \overline{\nu_{e}}$ The problem with this equation that it does not ...
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Can a material made of a heavier isotope of an element become harder or stronger?

I was wondering if any experiments have been done to measure if there is a change in the hardness or strength of a material made solely of a heavier isotope of an element which is a constituent of the ...
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Can a half life be given in electron volts?

I'm using this link to search for particular energies in which gammas may be emitted (for nuclide identification on a gamma spectrum). If on the above link you go down to the "γ condition #1" line, ...
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Showing that $\lambda$ is the probability per unit time that one particle will decay in 1 second

My textbook says that $\lambda$ is the probability per unit time that 1 particle will decay in one second. This makes absolutely no sense to me - I can see that it is related to probability but cannot ...
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Semiclassical interpretation of angular anisotropy in nuclear decay angular correlation studies?

Sometime ago a number of $\gamma-\gamma$, $\beta-\gamma$ and $\alpha-\gamma$ angular correlation studies were carried out to infer spin-parity assignments for cascades of decays from excited nuclear ...
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How effective are nuclear weapons in space?

When a nuclear bomb explodes it heats up the air surrounding it and a destructing shock wave is generated. Consider the same bomb exploding in space. This would be the case for example if we tried to ...
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Electric transition probability of a nucleus B(El)

This is a broad question. What are the implications of the B(El) values, that are used to explain the transition of a nucleus to a state where l units of angular momentum are transferred? What all ...
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Can a perfect insulator, i.e. matter devoid of all electrons conduct electricity?

Few weeks ago an article on Nautilus was published on Neutron stars. After reading that, a question was asked by a friend of mine. He asked if matter in neutron star would be able to transfer ...
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Meaning of mean free path expressed as kg/m^2?

In the paper "The Question of Pure Fusion Explosions under the CTBT" at reference 12, the equation for the neutron dose from the fusion of a small amount of DT gas is given, with a term of $90 ...
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Could the $\gamma$ ray “weaken law” be used in the air?

I'd better write it down. I do not know if it is called "weaken law" in English. $$N=N_0e^{-\mu d}$$ $N$ is the initial number of photons. $N_0$ is the amount measured after passing through an ...