Graph of potential energy versus internucleon distance in an atom

Click For Summary

Discussion Overview

The discussion revolves around the graph of potential energy versus internucleon distance in an atom, focusing on the behavior of potential energy as nucleons are separated. Participants explore the implications of this graph, including the forces at play and comparisons to other potential models.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • One participant describes the potential energy graph, noting a minimum at approximately 0.8 femtometers, with positive potential energy below this distance and negative above it, indicating attractive and repulsive forces at different separations.
  • Another participant suggests a comparison to the Lennard-Jones potential, proposing that nucleons could be treated as composite particles, which may help in understanding the strong nuclear force.
  • A different reference is provided that attributes short-range repulsion to the Pauli exclusion principle and medium-range attraction to Yukawa forces, linked to the exchange of massive mesons.

Areas of Agreement / Disagreement

Participants express interest in various explanations and models, but no consensus is reached regarding the interpretation of the potential energy graph or the underlying forces involved.

Contextual Notes

The discussion includes references to complex concepts such as composite particles and the Pauli exclusion principle, which may require further clarification or assumptions that are not fully explored in the posts.

Who May Find This Useful

Readers interested in nuclear physics, potential energy models, and the interactions between nucleons may find this discussion relevant.

kihr
Messages
98
Reaction score
0
The graph of potential energy of a pair of nucleons as a function of their separation shows a minimum potential energy at a value r (approx. = 0.8 femtometers). Below r the PE is positive (actually rises sharply from a negative to a positive value). Above r the PE is negative, and becomes zero beyond a certain value of r. For a separation greater than r the force on the nucleons is attractive, while for separations less than r the force is strongly repulsive.

I would appreciate if someone could explain the above phenomenon to me. Thanks.
 
Physics news on Phys.org
Have you seen the explanation for the similar shape of the Lennard-Jones potential between atoms? If not, you might find it interesting.

http://polymer.bu.edu/Wasser/robert/work/node8.html

You could try to apply this reasoning by treating the nucleons as composite particles (3xquark), and considering similar effects in the context of the strong nuclear force. In both cases you have a composite state. For the nucleons you have R,G,B quarks in each of the nucleons.

Torquil
 
Thanks. Let me have a look at your reference.
 
I think that this is also worth reading:

http://www.cartage.org.lb/en/themes/sciences/physics/NuclearPhysics/WhatisNuclear/Forces/Forces.htm"

It seems to explain the short range repulsion as coming from the Pauli explusion principle, and the medium range attraction as a Yukawa force, which appears as a consequence of the exchange of massive mesons.

Torquil
 
Last edited by a moderator:

Similar threads

  • · Replies 3 ·
Replies
3
Views
1K
  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 1 ·
Replies
1
Views
5K
  • · Replies 1 ·
Replies
1
Views
9K
  • · Replies 46 ·
2
Replies
46
Views
5K
  • · Replies 26 ·
Replies
26
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 2 ·
Replies
2
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 23 ·
Replies
23
Views
2K