Flux limit of cosmic-ray magnetic monopoles from a fully coincident superconducting induction detector

A superconducting inductive monopole detector consisting of six independent high-order planar gradiometers placed on the six faces of a 15×15×60-cm3 rectangular parallelepiped was operated from November 1983 to February 1985. This detector had a fully coincident-detection area of 0.1 m2. No monopoles were detected during an accumulated 9100 h of observation time, setting an upper limit of 5.5×10-12 cm-2 s-1 sr-1 (90% C.L.) for the cosmic-ray monopole flux. © 1985 The American Physical Society.