Speaker
Description
At SAGA Light Source (SAGA-LS), frequent beam losses caused by RF reflection trips of the RF cavity had been a serious reliability issue for stable operation. To improve operational reliability, we replaced the RF cavity with a new one in 2025. However, after the replacement, beam losses due to the RF reflection trips of the cavity still occurred. To investigate the cause, we analyzed the RF signals recorded from a high-resolution oscilloscope and the images obtained using CCD cameras viewing inside and outside of the cavity. At the same time, we continued RF conditioning of the cavity. As the RF conditioning progressed, the frequency of RF reflection trips significantly decreased. To further investigate and monitor the discharge, we installed an X-ray monitor to detect X-rays generated by field emission from the cavity surface. These X-ray measurements are intended to provide a non-contact method for monitoring changes in the cavity surface condition during RF operation and to contribute to more reliable operation of the storage ring.