A Search for highly ionizing particles produced at the OPAL intersection point at LEP

Abstract We report the results from a search for highly ionizing and magnetically charged particles at the OPAL intersection point at the LEP e + e − storage ring. The search was sensitive to Dirac monopoles with magnetic charge in the range 0.9 g D g g D , where 68.5 e ≡ g D . New upper limits are established on the production of monopoles with charge g D and mass up to 45.0 GeV/ c 2 .