The paper introduces the synchrotron radiation system for Hefei Light Source (HLS),which includes the streak camera system,the bunch length system using photoelectric method,the beam profile measurement system,and the photon beam position measurement system.The bunch length and bunch lengthening were measured using the streak camera system and the photoelectric method.The beam profile measurement system was used to observe the suppression effects of sextupole on beam transverse instability and the feedback effects of the transverse bunch-by-bunch feedback system.The photon beam position measurement system used two wire-type monitors and the logarithmic signal processor,which was used to detect the beam motions.
In this paper,in order to stabilize the position and angle of the light source point,a new photon beam position feedback system based on the Photon Beam Position Monitors was developed on Hefei Light Source,and used to correct the position drift and angle variation of the light source at the same time.On introducing the feedback principle,the transfer function matrix is calibrated,indicating that the new system is workable and effective.
The beam horizontal orbit at Hefei Light Source(HLS)was drifting all along while the storage ring was operating.To study this phenomenon,the displacement and the temperature variation of the BPM chamber were measured.By analyzing the measurement results,the main reason that explained the drifting phenomenon was found. The vacuum chamber following the dipole magnets was heated by the synchrotron light,which caused the increasing of the chamber surface temperature.The variation of the chamber temperature was the main reason why the BPM chamber held the horizontal displacement.To suppress the orbit drifting,a compensation method of BPM movement was proposed and its experimental results were given.
