What are these directional energetic particles?

Click For Summary

Discussion Overview

The discussion revolves around the identification of highly energetic particles observed in a cloud chamber, with a focus on their characteristics, potential identification as muons, and the implications of their directional behavior. The scope includes experimental observations and theoretical considerations related to particle physics.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant observes tracks in a cloud chamber that penetrate the entire width and are oriented parallel to the N/S compass axis, questioning if these could be muons.
  • Another participant suggests testing for charge using an applied magnetic field as a method to further investigate the particles.
  • A participant challenges the assumption that muons cannot create long trails due to their short lifetime, prompting a discussion about muon lifetime and speed.
  • One participant references the time dilation effect on atmospheric muons, explaining that this effect allows them to penetrate further into the atmosphere than expected, which may relate to the observed behavior in the cloud chamber.

Areas of Agreement / Disagreement

Participants express differing views on the identification of the particles, particularly regarding the implications of muon lifetime and the effects of time dilation. The discussion remains unresolved with multiple competing perspectives on the nature of the observed tracks.

Contextual Notes

Participants reference the average lifetime of muons and their speed, but the calculations and assumptions regarding their behavior in the cloud chamber are not fully resolved. The discussion includes considerations of relativistic effects that may influence observations.

Kosdon3200
Messages
13
Reaction score
10
TL;DR
In addition to the usual alpha and beta particles visible in my condensation cloud chamber, I see occasional tracks that seem highly energetic -they easily penetrate the entire width of the cloud chamber (10-12 inches) going in one side and out the other. What are they?
In addition to the usual alpha and beta particles visible in my condensation cloud chamber, I see occasional tracks that seem highly energetic -they easily penetrate the entire width of the cloud chamber (10-12 inches) going in one side and out the other. More mysteriously, their orientation is almost always of a vector parallel to the N/S compass axis. I am trying to determine if these are muons... but my understanding of muons is that they are too short lived to make such long trails. What are they and why the consistent vector?

Here's a link to what I've described above:
 
  • Like
Likes   Reactions: Paul Colby and berkeman
Physics news on Phys.org
You could possibly test for charge, using an applied magnetic field?
 
Kosdon3200 said:
but my understanding of muons is that they are too short lived to make such long trails.

Why do you think that? What is the muon lifetime? How fast do you think they are going? How far will they go in that time?
 
Vanadium 50 said:
Why do you think that? What is the muon lifetime? How fast do you think they are going? How far will they go in that time?
Thanks for the question. My original thought process was to take the average lifetime of 2.2 ms multiplied by the speed of light, but as I learned through some great writing about this very topic my method was overly simplified. See here:

Einsteins Relativity In The Palm Of Your Hand
 
The 'well known' effect of time dilation on atmospheric muons accounts for the fact that they penetrate much further into the atmosphere than would be expected. Measurements of muon flux at various heights on mountains show a very significant effect on their apparent half lives as they are traveling at speeds not far short of c.
 

Similar threads

  • · Replies 10 ·
Replies
10
Views
3K
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 6 ·
Replies
6
Views
3K
  • · Replies 2 ·
Replies
2
Views
8K
  • · Replies 9 ·
Replies
9
Views
4K
  • · Replies 9 ·
Replies
9
Views
3K
  • · Replies 11 ·
Replies
11
Views
4K
  • · Replies 4 ·
Replies
4
Views
8K
  • · Replies 10 ·
Replies
10
Views
3K