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

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Why does an atom remain uncharged after emission of an alpha particle?

When an alpha particle is emitted, two protons and two neutrons leave the nucleus but the electrons remain the same in number. Why does the atom remain uncharged although it appears it should have a ...
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In nuclear fusion reaction, what is the percentage of mass converted to energy?

I read somewhere that it is about one percent of the mass, but I find this too high. Also I have done some calculations, for example, the Tsar Bomba was 50 MT bomb and weighed about 27 tons. Although ...
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$\alpha$ decay to more than one nuclear state

I do not understand how $\alpha$ decay can be a probabilistic process such that there are multiple products from the decay. For example: $^{241}\mathrm{Cm}$ decays to the excited states of ...
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176 views

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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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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538 views

Deriving Gamow factor for potential with effective centrifugal potential term

I am looking at deriving an expression for the Gamow factor for $\alpha$-decay. I understand that the potential is the sum of the nuclear, electric and effective potentials: $$V(r) = V_N(r)+V_c(r) ...
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Can antimatter be used as fuel for nuclear reactors?

I completely understand the difficulties of making and storing antimatter, so I am not talking about the mechanism or the way of doing it here, I am just talking about the concept. As far as I know, ...
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721 views

The “binding energy” of bonded particles adds mass?

This is a follow-up my previous question. Several of the answers indicated that the mass of a particle (atom, proton, etc.) increase with the "binding energy" of it's component particles - the energy ...
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Where does the “borrowed energy” come from in Alpha decay?

I was also thinking about the uncertainty principle in regards with energy & time. The question of something like: Alpha tunneling out of the nucleus is where this can be invoked, but having an ...
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Direct nuclear reactions problems [closed]

can anyone explain Multi-step nuclear reactions in terms of direct nuclear reactions .
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(Iran's nuclear timetable) How IAEA knows that iran is able to make nuclear bombs in four months? [closed]

'Iran could have enough material for bomb within 4 months' actually its within 3 months now. I feel, iran will be able to produce nuclear weapons, given the weakness of Western. because West has no ...
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184 views

How can I destroy earth with physics? [closed]

I want to destroy the whole earth using physics, I would like to learn some of the ways that can be used to achieve this. I tried using a nuclear bomb but it takes so long, and I can't wait that much: ...
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407 views

How Does Lead Block Radiation

How is it that lead can block radiation, and things are lead lined. In the Indiana Jones 4 movie he climbs inside a lead-lined fridge and he somehow survives the blast and radiation?
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344 views

Would matter-antimatter annihilation create a fireball or not?

There has been a long discussion between me and Anna V on if the products of the annihilation will really cause a fireball to form and we haven't settled it yet. Our point here is that gamma rays ...
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264 views

We're all star dust?

OK so we've all heard of this from Carl Sagan, Lawrence Krauss and others and we know the argumentation, I don't refute that. There are other examples, for instance I once calculated (this was before ...
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284 views

Could we prove that neutrinos have mass by measuring their gravitational signature?

It is now said that neutrinos have mass. If an object has mass then it also emits a gravitational field. I appreciate the neutrinos mass is predicted to be small, but as there are so many produced ...
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Why can't Iron fusion occur in stars?

It is said that iron fusion is endothermic and star can't sustain this kind of fusion (not until it goes supernova). However star is constantly releasing energy from fusion of elements like Hydrogen ...
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285 views

What has $E = mc^2$ to do with nuclear powerplants?

In life, when you talk about nuclear energy, there always happens to be a guy who says that famous Einstein's equation. "Yeah, they just convert mass to energy, $E = mc^2$ ya know?" When I think ...
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611 views

If we assume that protons don't decay, then will all matter ultimately decay into Iron-56 or into nickel-62?

Wikipedia says that all matter should decay into iron-56. But it also says Nickel-62 is the most stable nucleus. So could this mean that in the far future, everything could (through quantum ...
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Strong force, where is the seperation?

In class I got given a diagram like this: (albeit without the Electrostatic force line) However the teacher told us the nucleons are typically separated when the force is zero. So as the string ...
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112 views

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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463 views

Why do nucleons feel a repulsive force when less than 1 fm?

My Modern Physics textbook by Taylor states that when nucleons are less than 1 fm apart, there is a strong repulsive force between them. I am fairly certain that it is not the Pauli Exclusion ...
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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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67 views

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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377 views

gamma ray lasers?

Is it really possible in the foreseeable future to create a gamma ray laser? I've read these two articles on Wikipedia: the Hafnium controversy Induced gamma emission It sounds pretty amazing, ...
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283 views

Pressures Necessary for Carbon Detonation

Carbon detonation is a characteristic event of Type 1a Supernova (EDIT: where an accreting white dwarf near the Chandrashankar limit of 1.4 solar masses explodes), an extremely important standard ...
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Does the Breit Wigner formula apply to intermediate virtual particles?

Breit Wigner Formula describes the cross section for interactions that proceed dominantly via a intermediate particle (O*) A+B → O* → C + D: $$σ = \frac{2\Pi}{k^{2}}\frac{Γ_{i}Γ_{f}}{(E-E_{o})^{2} + ...
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Would it be possible to detect nuclear explosion on exoplanet?

How strong would have to be nuclear explosion on exo-planet that orbits some other star for it to be detectable outside of that system. Or it would be impossible due to amount of radiation coming from ...
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118 views

Binding energy in fission

In nuclear fission the total rest mass of the products is less than the mass of the original nucleus. But on the other hand, the binding energy of the products is higher. Doesn't the decrease of the ...
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1answer
481 views

What is the speed of a neutral pion and how is it measured?

Alvager et al 1964 purportedly disproved Ritz's emitter theory in an experiment that generated neutral pions with a vellocity of $v =B.c$ where B is slightly smaller than one. How is the velocity of ...
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3k views

Would a matter-antimatter explosion cause fallout?

I know matter and antimatter annihilation release a lot of gamma rays which are considered ionizing radiation if I am not mistaken. But what if the explosion happened on the surface of the earth, ...
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507 views

Nuclear physics problem, Why do we use high weight atomic elements?

So as far as I know, nuclear fission uses high weight atomic elements to manufacture power. If the risk of runaway reactions are a major reason for not expanding this technology, why don't we use ...
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478 views

Electrical neutrality of atoms

How is it that atoms with equal numbers of protons and electrons are described as "electrically neutral" when the proton is 1,800 times more massive than the electron?
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Why do nuclear multipole moments of charge density vary with isotopes?

Why do some isotopes have different quadrupole/octupole moments, when these moments of charge density should be independent of mass?
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Why should odd-ordered electric multipole moments vanish?

In the multipole expansion of the radiation field of a nuclear, it is considered that the odd-ordered poles (like electric octupole) must vanish in order to conserve parity. But there exist many ...
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Binding energies of Be

Just a quick question. How does Beryllium 8 decay into 2 alpha particles? Beryllium 8 has a binding energy of 56.499508 Mev An alpha particle has a binding energy of 28.3 so two of these would have ...
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76 views

Which nucleus is the most resilient against gamma-induced fission?

To state the title question perhaps more precisely: What is the largest photon energy $E_{\gamma}$ and the corresponding mass number $A$ and atomic number $Z$ of a suitable nucleus ${}^A_ZX$ ...
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81 views

Use of fission products for electricity generation

Why can't we use fissions products for electricity production ? As far has I know fissions products from current nuclear power plants create enough 'waste' heat to boil water; and temperature ...
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What prevents an atom's electrons from “collapsing” onto its protons? [duplicate]

Forgive me if the answer to this is obvious. I have no formal physics training, and I remember that when I asked my physics teacher this, she just frowned and said "Good question." An electron is ...
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1answer
125 views

What is the minimum density required for nuclear fission?

This is a followup to a prior question I asked about gaseous nuclear fission. What is the lowest nuclear fuel density required to initiate fission? This is critical for a gas core reactor with a ...
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Ratio of Size of Atom to Size of Nucleus

I have the following problem: In nuclei, nucleons exists in nuclear energy levels and in atoms, electrons exist in atomic energy levels. The order of magnitude of nuclear energy is 1MeV whereas ...
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Explanation of energy levels in molecules, atoms, nuclei and their relationship

Why are the energy levels of molecules, the atoms that form them and the nuclei inside the atoms considered separately? Or phrased in a different way- what is it that makes their energy levels so ...
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432 views

Was the early Earth radioactive?

I've been reading of the (surprising) fact we are uncertain on whether there is nuclear fission in the center of the Earth or not (yet we know so much detail on structures at the other end of the ...
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In what environments can a dipolariton form?

In what environments can a dipolariton form? The article in Science in which it is introduced discusses it in the context of an optical cavity in a semiconductor. Can this quasiparticle occur ...
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How do we know that nuclear physics corresponds to low energy QCD?

One often hears the phrase "most of nuclear physics is in the low energy regime of QCD, where strong coupling constant is large ...", with the following diagram being invoked: How does one know ...
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Falling metal cylinders more devastating than a nuke?

I just saw G.I JOE - Retaliation. In the movie the bad guys (spoiler alert) Could this device cause more destruction than a nuclear weapon? If so, how?
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Is a nuclear bomb in some sense a bullet travelling at the speed of light, but along time rather than along space?

Apologies if this is a silly or perhaps obvious question, but $E=mc^2$ just looks so much like classical kinetic energy (except for the factor of 2). So I'm thinking of the to-be-fissioned-away ...