Search for Charge13eParticles in Cosmic Rays

Abstract
A search was conducted for particles of charge 13e (quarks) in cosmic rays at sea level. No such particles were found. The experiment yields an upper limit for the frequency of high-energy quarks of 1 per 2×105 relativistic μ mesons. This limit is related to a limit on the quark production cross section as a function of possible quark mass. A short discussion is given of macroscopic experiments which might have detected quarks in matter.