Beam loss measurement system for energy calibration

In order to measure beam energy in Hefei Light Source accurately, a new set of precise and sensitive beam loss measurement system is built, and a kind of plastic scintillator detector which has high detection efficiency for low energy photons is adopted. According to the measured signal of beam loss, a set of digital signal processing circuit is developed. The experimental results show that the beam loss measurement system meets the requirements of the spin resonant depolarization method and can obtain the change of the beam loss accurately and sensitively. The measuring principle and theoretical basis of spin resonant depolarization is also introduced.