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

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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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28 views

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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80 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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96 views

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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44 views

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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1answer
47 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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53 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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38 views

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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74 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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37 views

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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65 views

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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49 views

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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25 views

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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37 views

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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76 views

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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64 views

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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50 views

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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14 views

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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60 views

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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43 views

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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65 views

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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1answer
30 views

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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2answers
69 views

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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43 views

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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2answers
40 views

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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58 views

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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696 views

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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75 views

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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25 views

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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106 views

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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1answer
33 views

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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209 views

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 ...
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34 views

What is the reason behind the very high value of nuclear density? [closed]

I know how to arrive at the formula but I want to know it's such a huge number almost 2 X 1017 kg m-3, which is a huge number, all the more surprising to me is that it's a constant! Each and every ...
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Notation in a neutron star superfluidity

In this article "Neutron Star and Superfluidity", by Ka Wai Lou: http://guava.physics.uiuc.edu/~nigel/courses/569/Essays_Fall2010/Files/lo.pdf symbols as $^1S_0$ and $^3 P_2$ are shown, but I not sure ...
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Baryons annihilation

I was wondering if there is a way of calculate the annihilation cross section for two baryons, say $p\bar p\to\pi\pi$ or $p\bar p\to\gamma\gamma$. The problem here is that we cannot use the usual ...
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70 views

Atoms traveling at the speed of light [closed]

If an atom was to travel at the speed of light (although impossible), wouldn't the nucleus break apart? I say this because the particles holding the protons together in the nucleus wouldn't be able to ...
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How does mass affect the range of a nuclear particle?

Heavy particles such as protons and alpha particles of certain energy will lose all their energies in a definite distance in a medium, and this distance is called the range. The range is the distance ...
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Is there any aspect of an explosion resulting from a nuclear weapon test that cannot be simulated using super computers?

This Washington Post news article states that with the advent of computer simulation of nuclear tests, live tests are no longer needed. Generally speaking there are 3 aspects of an explosion ...
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40 views

Could anyone explain to me how the products of nuclear fusion/fission are predicted? [duplicate]

I have an idea of how quantum mechanics work, but I know too little to understand which products are a result of certain reactions like bombarding a certain atom with neutrons or just by natural ...
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28 views

Bonding Two Cationic Hydrogen Isotopes (protium) yields H2 or He?

If you have two hydrogen atoms. And they are the isotope form "Protium" (1 neutron removed) and they are also cationized +1 (1 electron removed) then you have (in a sense) a single proton (two of them ...
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1answer
15 views

Local nuclear magnetic field compared to macroscopic field

In an NMR experiment, I the local magnetic flux density of an iron sample was found to be roughly 33 T, by checking for a resonance frequency of the magnetic dipoles. How can it be that such a high ...
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1answer
131 views

$SU(3)$ Tensor Methods in a Tetraquark

I am trying to understand the Georgi chapter of tensor methods in $SU(3)$ representations, and I don't know how to resolve the tensor product of 2 matrices in a 2 heavy quark + 2 light antiquark ...
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37 views

Quark axial-vector current in nucleion

In almost all direct detection articles (see for example Jungman, G., Kamionkowski, M. & Griest, K., 1996. Supersymmetric dark matter) I found the following parametrization for the matrix element ...
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Peak in continous energy spectrum

I was reading online about particle decay. For the decay of Strontium-90 to Yttrium-90, a beta particle is emitted. The energy distribution of beta particle is continuous. If I know that the maximum ...
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1answer
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What is the relation between Nuclear magnetic resonance (NMR) and electron paramagnetic resonance (EPR)? [duplicate]

It seems to me that the basic principles are exactly the same, right? Then I am puzzled that the former was awarded a nobel prize while the later not. I noticed a similar question here What's the ...
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Disintegration of deuteron into n & p by a gamma ray - energy considerations

I was working through a problem that has a Deuteron of mass $M$ and binding energy $B$ disintegrated by a $\gamma$-ray of energy $E_\gamma$ into a neutron and proton. It proceeds to ask to find the ...