An underground search for anomalous slow penetrating particles

Abstract

We have searched for anomalous slow or highly ionizing particles by measuring the dE/dx and the time of flight of penetrating cosmic rays using a telescope of plastic scintillators placed underground. No evidence was found for anomalous particles, since it resulted a, flux limit (90% confidence level) of about 6.10-13 cm-2 sr-1 s-1 for magnetic monopoles in the velocity range 5.10-4 < β < 1. Similar flux limit was also obtained for slow charged particles with integer or fractional charges.