Study Of Bunch-by-bunch Beam Current And High-sensitivity Tune Measurement Systems At HLS ?

The major research of this thesis are the study of the bunch-by-bunch beam current and high-sensitivity tune measurement systems at HLS II.The bunch-by-bunch beam current measurement system use an ultra-fast photodetector to measure the emitted optical synchrotron radiation intensity directly,representing the bunch current intensity.The new high-sensitivity tune measurement system based on a diode peak detectors can obtain the tune with no added explicit excitation,which don't disturb the beam.This novel tune measurement system has the potential to be an online real-time instrument,which is of great value and vast foreground.Firstly,the physics of the accelerator storage ring are introduced qualitatively as a whole,and the basic concerts of transvers particle dynamic are derived for particle acceleration.The physical parameters closely related to the two systems we have designed,such as tune,beam current and synchrotron radiation,are also introduced.The basic theories of tune and beam current intensity in beam measurement and diagnosis are given.Secondly,the design and implementation of a bunch-by-bunch current measurement system based on synchrotron radiation are introduced.The basic situation of the B8 beamline of HLS ? is presented,and the optical path design of the bunch-by-bunch current measurement system is determined.The power of the synchrotron light at the photodetector is calculated,and the model of the ultrafast photodetector is determined to be the Hamamatsu G4176-03 MSM photodetector.The reconstruction of the time-domain waveform of the bunch using the equivalent time sampling algorithm is explained.In order to determine the absolute intensity of the beam,a DC current transformer(DCCT)system was used to obtain the DC current intensity.Error analysis and resolution tests are performed on the DCCT system.Using this beam current measurement system,a series of experiment are performed in the daily operation mode,single-bunch mode,and a Morse coded "HLS" fill pattern.Finally,the design and implementation of a high-sensitivity tune measurement system are introduced.The basic principle of 3D-BBQ technology are presented.Using the parameters of HLS ?,the front-end electronics module of 3D-BBQ are designed and simulated.According to the simulation results,a front-end electronics PCB board are fabricated.This high-sensitivity tune measurement platform are set up,and experiments are conducted to obtain experimental results,which compared with the existing swept frequency excitation tune measurement system to verify the design goals.