We have searched for anomalous cosmic-ray particles in a wide velocity range (3 × 10-4 < β < 1) by accurately measuring the time of flight and the dE/dx of downward and upward particle with six layers of scintillator hodoscopes placed 250 m underground. No anomalous candidate has been found other than the relativistic muons, setting an upper limit on the flux of 1.5 × 10-12 cm-12 s-2 sr-1 for magnetic monopoles in the velocity range 6 × 10-4 < β < 1. Similar upper limits on the flux are obtained also for slow massive integrally- or fractionally-charged particles and also for relativistic fractionally-charged leptons.
All Science Journal Classification (ASJC) codes
- Nuclear and High Energy Physics