Quarks and Leptons

Quarks and Leptons

1. Cosmic Rays

   • Either fast-moving protons or small nuclei
   • Collide with gas atoms in atmosphere
   • Create showers of particles and antiparticles
     • Can be detected at ground level
   • New particles discovered
     • Muon
       • -1 Charge
       • Rest mass x200 of electron
     • Pion
       • Can have all charges
         • Negative pion has Positive pion antiparticle
           • can decay into
             • Muon and antineutrino
             • Antimuon and neutrino
         • Neutral pion is its own antiparticle
           • Decays into high energy photons
       • Proton > rest mass > muon
       • Produced in twos through strong interaction
     • Kaon
       • Can have all charges
       • Proton > rest mass > pion
       • Produced in twos through strong interaction
       • Can decay into
         • Pions
         • muon and antineutrino
         • antimuon and neutrino