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

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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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Speed of fusion reactions compared to fission reactions?

How do the reaction rates of fusion and fission reactions compare? Is one faster than the other? What effect does this have on nuclear weapon designs?
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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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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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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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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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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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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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194 views

Question on spin-orbit interaction

When you study the spin-orbit interaction in quantum mechanics, even for a simple hydrogen atom, you find only the electric field in the nucleus reference system, while in the electron reference ...
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55 views

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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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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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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binding energy of a nucleus is positive?

I have found from this link http://hyperphysics.phy-astr.gsu.edu/hbase/nucene/nucbin.html that: Nuclei are made up of protons and neutron, but the mass of a nucleus is always less than the sum of the ...
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Is there a difference in the energy output of a nuclear fission reaction as opposed to fusion?

For example, if I split a Helium atom will I get the same amount of energy as when I fuse Hydrogen into Helium? If there is a difference, what will be the difference (in general not according to ...
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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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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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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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Why is technetium unstable?

Is there a simple account of why technetium is unstable? From the Isotopes section of Wikipedia's article on Technetium: Technetium, with atomic number (denoted Z) 43, is the lowest-numbered ...
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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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Stable Nuclei - Deviation from equal protons and neutrons

While studying the semi-empirical mass formula for nuclei, I came across an "asymmetry term" whose function, as far as I understand, is to build in the fact that nuclei "prefer" to have equal numbers ...
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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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60 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 ...
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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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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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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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XP Decay mode of radioactive nucleus

The decay mode of Carbon-8 is listed as 'XP' in this table. None of the references I looked at listed XP as a decay mode. What is it?
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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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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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66 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 ...
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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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119 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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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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282 views

Gamow peak and nuclear reaction rate

It's known that the nuclear reaction rate (inside a Star) can be determined with $$R_{ab}=n_a n_b\left<\sigma v\right> \, \approx \, n_a n_b \Big(\frac{8}{\pi m_e}\Big)^{1/2} ...
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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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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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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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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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How to choose which elements to use when synthesizing an ultra-heavy element?

I've been told that synthetic ultra-heavy elements are produced by bombarding a light nucleus into a heavy one, and that several combinations are (at least in theory) possible, as long as the sum of ...
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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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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 ...