Ultra high energy cosmic particles?

Click For Summary
SUMMARY

Ultra high energy cosmic particles, specifically protons with energies exceeding 3 x 1020 eV, have been detected traveling through the Earth's atmosphere. These particles, which approach the speed of light, are theorized to be accelerated by mechanisms such as Fermi acceleration and the influence of supernova explosions or black holes. Detection methods primarily involve analyzing air showers produced when cosmic rays collide with atmospheric molecules, utilizing technologies like the AGASA experiment and 'Fly Eye' detectors. The study of these particles is critical for understanding cosmic phenomena and their origins.

PREREQUISITES
  • Understanding of cosmic ray physics
  • Familiarity with Fermi acceleration theory
  • Knowledge of particle interactions in high-energy physics
  • Experience with air shower detection methods
NEXT STEPS
  • Research the AGASA experiment and its findings on cosmic rays
  • Study the principles of air shower detection and analysis
  • Explore the role of supernovae in cosmic ray production
  • Investigate the effects of Cherenkov radiation in particle detection
USEFUL FOR

Astronomers, physicists, and researchers interested in high-energy cosmic phenomena, as well as students studying particle physics and cosmic ray detection methods.

tozhan
Messages
28
Reaction score
0
ultra high energy cosmic particles??

I know there have been serveral instances where protons have been detected traveling through our atmosphere with energies in excess of 3*10^{20} eV. This means that they might cause macroscopic effects as the proton would be traveling at speeds close to C. I am just wondering if anyone can come up with a theory as to why and how this can happen??

I don't think its been solved so feel free to include random new strange theories, i enjoy reading them! :rolleyes:

PEACE!
 
Last edited:
Physics news on Phys.org
One of the theories for the high velocities of cosmic rays is called Fermi acceleration. It postulates that cosmic rays are accelerated by magnetic fields
 
tozhan, do you have any references or sources which identify the method for detecting or discovering 3E20 ev (3E8 TeV) protons?

Those energies are more than 3E11 times the rest energy (938.3 MeV), so the velocities would certainly approaching the speed of light.
 
Astronuc said:
tozhan, do you have any references or sources which identify the method for detecting or discovering 3E20 ev (3E8 TeV) protons?

Those energies are more than 3E11 times the rest energy (938.3 MeV), so the velocities would certainly approaching the speed of light.
While not a direct answer to your question Astronuc, this paper ("Cosmic Physics: The High Energy Frontier", F.W. Stecker) is one of my favourites as an overview of the field. It contains plenty of references ... I think you'll find that the most energetic CR was detected by the Japanese AGASA experiment, and that 'Fly Eye' detectors have also been used. Basically, the method(s) involve detection and analysis of air showers.
 
Cosmic Rays in general are believed to be created from supernova explosions in our galaxy and possibly from other galaxies. Protons are ejected from the explosion at extremely high velocities, although this doesn't completely explain where the extremely high energy comsmic rays (10^20 eV) come from. There is only speculation about where these extreme high energy CR come from, if i recall correctly, one possibily is because of a special type of supernova, one so violent that it causes the creation of a black hole. Another possibility is from the acceleration of protons because the the enourmus magnetic fields caused by spinning black holes and very fast spiraling ionized gas falling into the black hole.
This past summer I went to Brookhaven National Laboratory to study cosmic rays and build detectors for them. The design of the detectors were pretty simple, made of mainly dopped lucite and a Photo-Multiplier tube. When a cosmic ray enters our atmosphere traveling at very high speed, it travels a down a great deal until it reaches relativly dense air, and then collides with an air molecule. The collision causes a series of events leading to a shower of particles. The collision between a proton and an air molecule would produce mainly pion, which are composed of a pair of quarks. There would be positive pions (antipions), negative pions, and neutral pions. A positive pion would decay into a positive muon (antimuon), and then into a positron along with certain flavors of neutrinos. A negative pion would decay into a muon, and then into an electron along with other flavors of neutrinos. The neutral pion is a quark/antiquark pair, and therefore decays almost instantly into two xray/gamarays going in opposite directions in order to conserve momentum. The photons will then interact with heavy nucleii in the atmosphere and convert into an electron/positron pair. Once a particle from this shower goes through the lucite in the detector, it will emitt Cherenkov radiation, which will be detected by the PM tube and converted into an electrical signal that can then be analysed.

ps. sorry for my terrible spelling
 
Last edited:


I was reading that some of these ultra high energy cosmic rays had the amount of kinetic energy as a small golf ball moving @ 90km/h+?

Would you feel or get injured if getting hit by one of these cosmic rays at that energy?
 

Similar threads

  • · Replies 2 ·
Replies
2
Views
1K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 10 ·
Replies
10
Views
2K
  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 43 ·
2
Replies
43
Views
5K
  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 11 ·
Replies
11
Views
2K
Replies
1
Views
1K