NATS 1740 Lecture Notes - Lecture 5: Pion, Bootstrap Model, Antineutron

• School: York University
• Department: Natural Science
• Course: NATS 1740
• Professor: Radu Campeanu

Document Summary

Describe the two main types of experiments. What is a gev and why do we use this unit to measure particle masses. Experiments with cosmic rays or with particles from accelerators produced a large number of new heavy particles, most of them with very short lives. A first attempt to categorize particles was based on their weight. One way to think of spin is to imagine the particles like little tops spinning about an axis. Better interpret spin as a measure on how the particles look from different directions. It appears that the universe contains two types of particles: fermions with spin and bosons with integer spin (0,1,2). Fermions make up the matter in the universe. Bosons are associated with the mechanism of forces. After 1950 hundreds of new particles (baryons, mesons, leptons) were discovered. Their lives were short by comparison to events in macro but very long by comparison to the collision time.