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

learn more… | top users | synonyms (2)

7
votes
1answer
1k views

How did Enrico Fermi calculate the classical Fermi Problem?

From Wikipedia: Fermi was known for his ability to make good approximate calculations with little or no actual data, hence the name. One example is his estimate of the strength of the atomic bomb ...
2
votes
0answers
84 views

How can I determine the feasibility of Pd(d,f) fission chains?

The conclusion of this paper (p. 6) discusses some hypothetical Pd(d,f) yields as a possible explanation for anomalous results that the author observed. Suspending disbelief in the data reported in ...
4
votes
2answers
1k views

What happens if we put together a proton and an antineutron?

A hydrogen nucleus consists of a single proton. A 2-hydrogen (deuterium) nucleus consists of a proton and a neutron. A tritium nucleus consists of a proton and two neutrons. This makes me wonder how ...
10
votes
2answers
241 views

Nuclear physics from perturbative QFT

Is there a renormalizable QFT that can produce a reasonably accurate description of nuclear physics in perturbation theory? Obviously the Standard Model cannot since QCD is strongly coupled at nuclear ...
1
vote
0answers
246 views

Any undergrad exercises about nuclear bomb design? [closed]

Are there any handy exercises about nuclear weapon design that are suitable for advanced undergrads in a nuclear physics or similar level physics course? I'm most curious about questions that ...
4
votes
4answers
10k views

Where do electrons get their ever-lasting circulating energy?

We all know (or maybe know) that to move, we need to spend energy. If you want to drive a car, you gotta spend gasoline. We also know that energy can't be created (first law of thermodynamics, and ...
1
vote
1answer
2k views

How does electron capture occurs?

Electron capture is a kind of decay by which a nuclear transformation takes place. Below is an example of it. $$ _{29} ^{64} \text{Cu} + e^- \rightarrow _{28}^{64} \text{Ni} $$ Of course, nucleus ...
3
votes
1answer
255 views

Can stable nuclei theoretically fission through quantum tunneling?

As I understand it, an unstable nucleus is going to randomly fission because the forces binding it together are momentarily weaker than the electrostatic repulsion of the protons. Given that some ...
8
votes
5answers
593 views

Why is storage of spent nuclear fuel dangerous?

Just what the title states; there's a good deal of noise made about transport, and storage of spent nuclear fuel. Why all the hullabaloo when the fuel is all spent?
6
votes
1answer
365 views

Does neutron radiation form clouds?

I've heard a couple of scary stories from experienced accellerator physiscists about something called neutron clouds. Apparently, if you have an experiment like a fixed-target experiment that produces ...
7
votes
1answer
263 views

How would nucleosynthesis be different if the neutron were stable?

If the strong nuclear force were just 2% stronger, the neutron would be a stable particle instead of having a half life of about 13 minutes. What difference would that have made to Big Bang ...
8
votes
1answer
370 views

Island of Stability

When I was much younger, I remember being fascinated by the thought of an Island of Stability at very high atomic numbers. However, I have not heard much on this and I was wondering Did this idea ...
3
votes
1answer
451 views

Why the pion does not get mass under Spontaneus breaking of chiral symmetry, but the quarks do?

Some sources state that when the mass of a quark goes to zero, it allows for Spontaneous Breaking of Chiral Symmetry and gets a constituent mass of about $200\, \mathrm{MeV}$. Other sources state ...
3
votes
1answer
800 views

Question about a nuclear bomb test photo

What are those white lines connecting the ground to the sky on the left side of this photo? I've see these before in the nuclear bomb test films too. They're apparently already in place upon ...
7
votes
3answers
3k views

Why is beta negative decay more common than beta positive?

In simple terms, why is beta negative decay more common than beta positive? I know it's something to do with occuring inside/outside the nucleus - but I can't find a simple, easy to understand ...
2
votes
1answer
95 views

Creation of Nuclear Isomers

As I understand it, if a nucleus is excited with energy exceeding its ground state, it releases energy via gamma radiation. An example would be technitium 99m, a medical tracer with a 6 hour half life ...
1
vote
0answers
95 views

Is it possible to create a nuclear reactor the size of a melon? [duplicate]

Possible Duplicate: What is the minimum amount of fissile mass required to acheive criticality? I want to make a red laser the only problem is that the power is not sufficient so I had to ...
0
votes
2answers
176 views

Synthesizing elements (Nuclear Physics/Alchemy?)

Based on my limited knowledge of nuclear physics, it seems that one day it may/will be possible to synthesize whatever elements we may need, given enough energy. Is this accurate? Is there a table ...
4
votes
1answer
519 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 ...
4
votes
4answers
4k views

Why are nuclear reactors dome/bell shaped?

Just what the title states. What is the reason that a Nuclear reactor has a characteristic dome/bell shape?
4
votes
2answers
2k views

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 ...
3
votes
2answers
801 views

What are nuclear isomers? What is isomeric energy?

Can someone explain nuclear isomers to me, and in particular what the energy involved is? I understand generally that we're talking about moving from a less to more stable configuration of nuclear ...
8
votes
6answers
1k views

How do we know that C14 decay is exponential and not linear?

In my previous question I asked Please explain C14 half-life The OP mentioned that I was thinking of linear decay and C14 was measured in exponential decay. As I understand it, C14 is always in a ...
1
vote
0answers
463 views

Please explain C14 half-life [duplicate]

I understand that C14 decays at a given rate. I also interpret this to mean that 100% of the atoms of C14 in an object will all decay at the same right, individually. So if I have 4 C14 atoms, will ...
0
votes
1answer
184 views

Leaching of radiometric material, is it possible?

I've been doing some reading about radiometric dating and I've come across an interesting find. If anybody has any additional information on this, that would be great. First my question: In regards ...
-2
votes
2answers
2k views

How reliable is Radiometric dating? Are there limitations? [closed]

Young earth creationists dismiss radiometric dating as unreliable, whats the truth?
2
votes
1answer
329 views

How does the internuclear repulsion vary in Hydrogenic atom collision?

Hydrogen fusion requires two hydrogen nuclei to get close enough (typically a few fm) to fuse. Much of the problem of creating a fusion reactor is overcoming the Coulomb repulsion between a pair of ...
2
votes
1answer
525 views

What are the average matter, antimatter, and binding energy composition of protons and neutrons?

For a free baryon at rest at room temperature, how much of its ~1Gev (rest) mass can (on average) be considered as matter, as antimatter, and as binding energy? For a baryon in a nucleus, I assume ...
11
votes
4answers
492 views

How do we know that the nucleus isn't a quark-gluon plasma?

The standard picture of the nucleus of atom is that is several distinct nucleons, which themselves are composed of quarks. However, it seems to me like a much simpler picture is that the nucleus is ...
3
votes
2answers
2k views

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 ...
13
votes
1answer
561 views

How come random matrices can predict energy spectra of heavy atoms?

Some of the applications of random matrices is to find the spectra of heavy atoms in nuclear physics which are usually difficult to find otherwise. How can starting from randomness of some kind, ...
6
votes
3answers
1k views

Does the “Energy Catalyzer” by Andrea Rossi et al. generate energy by converting Nickel to Copper?

From Wikipedia: The Energy Catalyzer is an apparatus built by [...] Andrea Rossi, [and] Sergio Focardi. The 2009 patent application claims "a method and apparatus for carrying out nickel and ...
7
votes
1answer
3k views

What is so special about iron?

I remember reading something about how iron was a highly stable element. Ever since then, I have looked at iron fry pans with new-found respect. However, in a recent discussion I was unable to ...
1
vote
2answers
250 views

Is it viable to convert nuclear waste into safe isotopes?

I read that powerful pulsed lasers can change isotopes: J. Magill, et. al.: "Laser transmutation of iodine-129". Did anyone estimate what would be the energy costs to transmutate 1 kg of fission ...
7
votes
2answers
480 views

What elements can be created in the fusion process of different types of stars?

As I understand it fusion inside a sun can produce heavier and heavier elements until some sort of "nucleus size limit" is reached. As far as I understand, the limit is thought to be reached with the ...
12
votes
2answers
440 views

Hydrogen as a fuel in Sun

The source of Sun's incessant energy is hydrogen; which is continuously converting to helium through nuclear fusion reaction releasing energy. Why does not all hydrogen convert into helium in one big ...
1
vote
3answers
636 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 ...
3
votes
5answers
6k views

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 ...
65
votes
6answers
7k views

Why is there a scarcity of lithium?

One of the major impediments to the widespread adoption of electric cars is a shortage of lithium for the batteries. I read an article a while back that says that there is simply not enough lithium ...
6
votes
2answers
2k views

Tunneling of alpha particles

Consider this explanation of the alpha decay: It says The Coulomb barrier faced by an alpha particle with this energy is about 26 MeV, so by classical physics it cannot escape at all. ...
3
votes
0answers
2k views

Energy Levels of 3D Isotropic Harmonic Oscillator (Nuclear Shell Model)

One simple way of detailing the very basic structure of the nuclear shell model involves placing the nucleons in a 3D isotropic oscillator. It's easy to show that the energy eigenvalues are $E = ...
2
votes
3answers
463 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 ...
0
votes
0answers
191 views

Does the Standard model allow for radioactive decay prediction? [duplicate]

Possible Duplicate: Predicting Decay Rates via the Standard Model More specifically, does (any) current theory allow for approximate or exact predictions of atomic decay rates and types ...
2
votes
2answers
494 views

Nuclear physics Radioactivity

90Sr has a half life of 28.5y. It is chemically similar to Ca and enters the body through the food chain and collects in bones. It is a serious health hazard. How long in (years) will it take for ...
12
votes
3answers
4k views

Protons' repulsion within a nucleus

Do the protons inside the nucleus repel each other by the electrostatic force? If they do, why doesn't the repulsion drive the protons apart so that the nuclei get disintegrated?
3
votes
1answer
237 views

The vacuum as trigger

Do the apperance in the atomic nucleus of virtual matter-antimatter particle pairs play a role in the random nature of radioactive decay?
23
votes
4answers
14k views

Why do electrons occupy the space around nuclei, and not collide with them?

We all learn in grade school that electrons are negatively-charged particles that inhabit the space around the nucleus of an atom, that protons are positively-charged and are embedded within the ...
3
votes
1answer
205 views

$\frac{1}{\sqrt{2}}$ (|Independent particle Model⟩+ |Strong Interaction Model⟩)?

What is an adequate way to understand this simultaneously. One has the underlying assumption that matter is saturated and has the merit of being able to come up with an accurate formula for the ...
5
votes
1answer
519 views

Matter-antimatter annihilation

What happens if different size atoms meet? We've just created anti-helium, I think. What if one atom of anti-helium collided with one atom of iron. Would some of the iron be left over as a new ...
2
votes
2answers
457 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?