Abstract
Acoustic emission (AE) from small superconducting coils has been analysed aiming at the application to the monitoring system of large-scaled magnet. It was clarified that AE monitoring was useful for investigation of mechanical disturbances in the magnet. The origins of AE during magnet operation were investigated, and confirmed that it was originated from mechanical disturbances such as wire motion and/or epoxy cracking. The AE during cooling down or that after the quench has also been analysed to detect the instabilities. The results suggest that the AE from the magnet accompanied with temperature change reveals the degradatios of the magnet performance.
