Nuclear physics is the study of the composition, behavior and interaction of atomic nuclei and their constituent parts.
6
votes
4answers
2k views
Where does the energy from a nuclear bomb come from?
I'll break this down to two related questions:
With a fission bomb, Uranium or Plutonium atoms are split by a high energy neutron, thus releasing energy (and more neutrons). Where does the energy ...
2
votes
2answers
2k views
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?
3
votes
1answer
687 views
Why must the deuteron wavefunction be antisymmetric?
Wikipedia article on deuterium says this:
The deuteron wavefunction must be
antisymmetric if the isospin
representation is used (since a proton
and a neutron are not identical
particles, ...
6
votes
1answer
606 views
Why doesn't orbital electron fall into the nucleus of Rb85, but falls into the nucleus of Rb83?
Rb83 is unstable and decays to Kr-83. Mode of the decay is electron capture. Rb85 is stable.
The nuclei Rb83 and Rb85 have the same charge. Rb85 is heavier than Rb85, but gravitation is too weak to ...
10
votes
3answers
874 views
Age of the Earth and the star that preceded the Sun
One of the great unheralded advances made in the history of science was the ability to determine the age of Earth based on the decay of isotopic uranium. Based on the apparent abundance of uranium in ...
11
votes
5answers
732 views
How many times has the “stuff” in our solar system been recycled from previous stars?
Is there a cosmologist in the house? I've got a basic understanding (with some degree of error) of some simple facts:
The Universe is a little over 13 billion years old. Our galaxy is almost that ...
2
votes
1answer
284 views
Cherenkov radiation in nuclear bomb
Would Cherenkov radiation occur at the explosion of a nuclear bomb? Suppose it would not be occluded by smoke or anything else for that matter.
9
votes
6answers
778 views
Is there any thing other than time that “triggers” a radioactive atom to decay?
Say you have a vial of tritium and monitor their atomic decay with a geiger counter. How does an atom "know" when it's time to decay? It seems odd that all the tritium atoms are identical except with ...
6
votes
2answers
254 views
Weak contribution to nuclear binding
Does the weak nuclear force play a role (positive or negative) in nuclear binding?
Normally you only see discussions about weak decay and flavour changing physics, but is there a contribution to ...
8
votes
3answers
674 views
What does a nucleus look like?
It's a Christmas time and so I hope I'll be pardoned for asking a question which probably doesn't make much sense :-)
In standard undergraduate nuclear physics course one learns about models such as ...
3
votes
1answer
630 views
Fermi's Golden Rule
It is well known that to calculate the probability of transition in the scattering processes, as a first approximation, we use the Fermi golden rule. This rule is obtained considering the initial ...
1
vote
2answers
218 views
Isotope properties plotting tool?
I'm looking for something that will generate scatter plots comparing different properties of isotopes. Ideally I'd like some web page that lets me select axis and click go but a CSV file with lost of ...
14
votes
1answer
466 views
Turned to steel in the great magnetic field
This is obviously a "fun" question, but I'm sure it still has valid physics in it, so bear with me.
How great of a magnetic field would you need to transmute other elements into iron/nickel, if ...
5
votes
5answers
2k views
Is it possible to obtain gold through nuclear decay?
Is there a series of transmutations through nuclear decay that will result in the stable gold isotope ${}^{197}\mathrm{Au}$ ? How long will the process take?
10
votes
3answers
762 views
Why some nuclei with “magic” numbers of neutrons have a half-life less than their neighbor isotopes?
It's easy to find the "magic" numbers of neutrons on the diagrams of alpha-decay energy: 82, 126, 152, 162. Such "magic" nuclei should be more stable than their neighbors.
But why some nuclei ...
14
votes
3answers
4k views
Why is the nucleus of an Iron atom so stable?
Lighter nuclei liberate energy when undergoing fusion, heavier nuclei when undergoing fission.
What is it about the nucleus of an Iron atom that makes it so stable?
Alternatively: Iron has the ...
15
votes
5answers
705 views
How does Positronium exist?
I've just recently heard of Positronium, an "element" with interesting properties formed by an electron and positron, and I was shocked to hear that physicists were actually working with this element, ...
3
votes
1answer
182 views
How is it possible to calculate the energy liberated by a given fission process?
How is it possible to calculate the energy liberated by a given fission process? For example, in the fission of a $^{235}$U induced by capturing a neutron?
2
votes
1answer
210 views
Obtaining isotope stability
For a given isotope, one can obtain the binding energy using the semi-empirical mass formula.
For example, has a binding energy of 1782.8 MeV. From this information, how can the likelihood of the ...
