THE SEARCH FOR MAGNETIC YONOPOLES IN MAGNETITE FROM NORTH CHINA

Using the 27 KG magnetic field produced by a superconducting solenoid we have searched for trapped magnetic monopoles in a magnetite sample from North China. We have scanned the nuclear emulsion both for low ionizing tracks and heavily ionizing tracks, and the plastic film for heavily ionizing tracks of magnetic monopoles. We obtain a 90 % confidence level upper limit of 1.8x10^-26 monopoles per nucleon in the magnetite sample.