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

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Is Uranium renewable, or will this science fiction scenario become reality?

In my imagination, nuclear power could disapear when we use up all the uranium generating electricity, or exploding nuclear bombs. Is uranium a renewable resourse? if not, can we prove that this ...
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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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Russian Doll Teller Ulam?

Can you trigger a thermonuclear explosion from a smaller thermonuclear explosion in a scaling way, so that starting from a small laser ignited fusion within a small fissile container, using the X-rays ...
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Can I move the atom nucleus only?

I was wondering if it is possible to move the atom nucleus and leave behind the electrons? I can imagine that the electrons will follow the nucleus. But what if the speed of the nucleus is almost the ...
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What is nuclide notation referring to? Only the nucleus or the whole atom?

sorry that this is an easy question but I am just a bit confused about nuclide notation. When you say e.g. $^{240}_{94}\text{Pu}$, are you referring to the atom of $\text{Pu}$ or only its nucleus? It ...
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Atomic nucleus consisting of only neutrons?

Is it true that the nucleus of all atoms (including radioactive isotopes) contain at least one proton? Is there an atomic nucleus consisting entirely of neutrons? (Let's exclude neutron stars for the ...
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What is the shielding in nuclear reactors mainly against?

I have a little knowledge about ionizing radiation and I have been confused over why nuclear reactors need these massive shields. So, if I am not mistaken, Alpha and Beta radiation are not that ...
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Is it possible that nuclear fission contributes to climate change?

This is probably a really stupid question, please forgive me. Is it possible that the use of nuclear fission on earth contributes to the increased energy in the Earth's system as according with the ...
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Conversion of mass to energy in chemical/nuclear reactions

Is mass converted into energy in exothermic chemical / nuclear reactions? My (A Level) knowledge of chemistry suggests that this isn't the case. In a simple burning reaction, e.g. $C+O_2\to ...
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Evidence that nuclei contain neutrons and protons (other than nucleons appearing if a nucleus is smashed)?

This may seem like a silly question, but I believe this to be very fundamental because the Standard Model of particle physics seems based on the axiom or assumption that neutrons and protons exist ...
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Tritium decay is spontaneous even if the binding energy of tritium is higher than the binding energy of 3He. Why?

Given this nuclear reaction: $^3_1\mathrm H\to {}^3_2\mathrm{He}+e^-+\bar{\nu}$ and knowing the binding energies: $BE(^3_1\mathrm H)=8.48 \,\mathrm{MeV}$ $BE(^3_2\mathrm{He})=7.72 \,\mathrm{MeV}$ ...
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Does the Nuclear reaction happen inside the fuel rods?

I've been reading up on nuclear reactors, and understand explanations of how it works, how water is heated to steam, which turns the turbines, etc.. I understand all of the safety features, and how ...
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Kinetic energy of alpha-particle in $^{212}$Po decay

Admittedly, Nuclear Physics is not my strength. I'm writing a simulation to model alpha-decay. So far, I have looked up the values of the kinetic energy of the alpha particles that are emitted in a ...
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Einstein's mass-energy relation

Suppose we have 1 kg of wood and 1 kg of uranium and if we need to find out how much energy would each of the substance give, we'd have to use Einstein's mass-energy relation as follows: In the case ...
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Nuclear reactor control rods

What is the relation between control rods surface exposed into a nuclear reactor and neutron energy? Is it linear? I mean, how do neutron absorbing rate change with the progressive immersion of ...
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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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258 views

Theoretical Stability of “AB-matter”

Alexander Bolonkin has proposed the possibility of manipulating nucleons to produce stable, macroscopic structures of nuclear matter at zero pressure (which he calls "AB-matter"), by analogy with the ...
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280 views

How clean will first generation fusion reactors be compared to fission reactors?

Googling the topic seems to indicate that fusion reactors will produce less waste and less toxic radioactivity, but this fact never seems to be mentioned during the current debate over nuclear power. ...
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Neutron decay and particles

On this picture you can see that this $d$ quark turns into $u$ quark and makes this $W^-$ boson. $W^-$ then apparently turns the anti-electron neutrino, $\bar{\nu_e}$, into an electron, $e^-$. My ...
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How does a noseblow counter detect alpha radiation?

After working in air fed suits,operatives are required to give samples from their nasal passages by blowing their nose into a tissue,which is then counted in a noseblow counter. How does this work?
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How were the heavy elements from iron to uranium made? [duplicate]

Possible Duplicate: Age of the Earth and the star that preceded the Sun How were the heavy elements from iron to uranium made? References: ...
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Strongest force in nature

Possible Duplicate: What does it mean to say “Gravity is the weakest of the forces”? It is said nuclear force is the strongest force in nature.. But it is not true near a black ...
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Why do nuclear weapons create a blast wave?

As far as I know, in a nuclear explosion the energy is released in the form of radiation (neutrons, gamma rays, alpha particles and electrons), light and heat. There isn't a chemical reaction that ...
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The original thorium reactor?

With lunar thorium being common, and heavier than iron or nickel, does earth's core have the the occasional nuclear reaction?
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Radioactive decay - What mechanism decides when an unstable nucleus decays?

My first question on Stackexchange (if it is formatted wrong or something please tell me so I know in future) - here it is: Given an unstable nucleus (exactly which nucleus is not particularly ...
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Do atomic nuclei have fixed orientation and position with respect to the electron cloud?

Does the nucleus of an atom of any element (besides protium) maintain a particular orientation in relation to its electron cloud? Does it bounce around within its cloud? Can it be ejected from its ...
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Proton-Neutron Lattice as a form of matter?

Would it be possible for a lattice of protons and neutrons (I'm picturing a plane of hexagons in my head) to exist bound by the strong nuclear force (not gravity)? I know that the strong force losses ...
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Effect of temperature on radioactivity?

I'm researching the effect of temperature on uranium radioactivity, however I can't find any solid empirical evidence to prove the notion that temperature does not affect radioactivity. Can anyone ...
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How much radiation exposure in the US was caused by the 105 nuke tests in the Pacific?

Between 1947 and 1962 the US conducted 105 tests of nuclear weapons in the "Pacific Proving Grounds". I'm wondering how much radiation exposure resulted on the west coast of the US. These were part of ...
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Binding energy and mass

I’ve been told that a greater binding energy means the nucleus is more tightly bound, and therefore that decreases the mass of the nucleus with respect to its nucleons when separated. But why does a ...
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Why is the energy spectrum of alpha decay discrete?

Are the other peaks with lower energy caused by the possibility that daughter nuclei have to be in excited states?as show in this link (count versus energy)
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Why are neutron absorption cross sections high at low incident energy?

For example, U-235 fission cross section looks like this: As I understand it, the resonances peaks correspond to discrete quantum states of the excited compound nucleus. As you go higher, the ...
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About Nuclear magnetic resonance

I'm trying to understand the basic principles of Nuclear Magnetic Resonance reading this link but I have some doubts: 1) I have ever known that when protons aren't in a magnetic field, their spins ...
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Would being underwater help survive a nuclear bomb?

If I jump in my pool, on the river near my house knowing that a nuclear bomb, or atomic or H-Bomb exploded around 10 km from my house, would I survive? The way I see it is that water will protect me ...
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pp chain gamma decay / intermediate state

Based on the first equation at http://en.wikipedia.org/wiki/Proton%E2%80%93proton_chain_reaction $$_1^{1}H+_1^{1}H \to _2^{2}He+\gamma$$ Is it correct to say that in the P-P chain two hydrogen atoms ...
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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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The synthesis of $^{254}\text{No}$

How is $^{254}\text{No}$ synthesised? Could you explain the reaction where it is preceded by $^{208}\text{Pb}(^{48}\text{Ca}, 2\text{n})$? References to articles are well enough—I was somehow unable ...
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988 views

What is the relationship between earthquakes power and nuclear explosions?

What is the relationship between earthquakes power and nuclear explosions? How to compared power of earthquake with nuclear explosion?
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How do people get the proton number for each element from experiment?

How did people determine the proton number for each element from experiment in each decade of 20th century?
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critical density to create macroscopic nuggets of nuclear matter

Is there a critical size that an hydrogen bomb detonation needs to have in order to produce neutron-degenerated matter? Does anyone knows if matter in this state would be stable at ambient ...
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Ratio of radiation sources in the uranium cycle

Sorry, I know y'all are probably getting a lot of questions re: Fukushima, but I had a very specific one and no-one has been able to answer it. I am specialised in medical radiation, and have been ...
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Effect on electron shells energy levels during nuclear decay

First thanks for this great site. I was recently looking at photon emission from electron transitions from excited electron states in atoms. For simplicity I was using the Rutherford Bohr Model and ...
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What's the slowest nuclear decay rate that's been measurably linked with a narrow energy linewidth?

As was explained in the question What is the relation between the half-time and the line-width of a radioactive nucleus?, the half-life $\tau$ of an unstable nucleus is related to the linewidth ...
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What does 'channel' mean?

I see many plots like the following that graph counts per channel, I know what a 'count' is, but I don't know what a 'channel' is. Could somebody please explain to me? My guess is that it is that ...
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Can neutrons be synthesized purely from protons and electrons?

Can neutrons be synthesized purely from protons and electrons? Note: I'm looking for reactions that do not require neutrinos or any particles besides just protons and/or electrons as reactants.
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What is relationship between Quantum tunnelling and Gravitational potential energy of stars?

Are there a direct mathematical relationship between Quantum tunnelling and Gravitational potential energy of stars? The true source of the Sun's energy was shown by Hans Bethe to be nuclear fusion ...
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How do substances with like charges repel each other?

I have read in a number of places how substances with opposite charges attract each other: The excess electrons in the one substance repels the electrons in the other substance so that they move away ...
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How is energy produced in Alpha emission (radioactivity)?

In the above Alpha decay reaction, we get thorium by the alpha decay of uranium with an alpha particle. But we also get energy of amount Q by this process. And according to my course books, this Q ...
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“Dynamic Albedo of Neutrons” and all these Farnsworth fusors

I've checked specs of Russian "Dynamic Albedo of Neutrons" module on Mars MSL rover - it can do 10^8 neutron pulses at 10 pulses per second. It works on D-T reaction in tiny linear accelerator, and ...
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Phase space suppression

In talking about production/decay processes, I've heard people speaking of decay modes or cross sections being 'phase space' suppressed. For example, a two body final state is more likely to occur ...