Research Of Clock And Trigger Synchronous Method For HPGe Spectrometer At White Neutron Source CSNS

Neutron science plays an important role in the research of nuclear physics.Since Chadwick found the existence of neutrons through experiments,the scientific exploration of neutrons has never stopped.With the deepening of the knowledge of neutrons,people use the radioactive neutron source established by radioactive elements,the neutron source established by nuclear fission reactor and the current spallation neutron source.With the continuous improvement of neutron flux and the improvement of neutron spectrum,neutron has gradually developed into a powerful tool for human to study microstructure and material properties.Neutron induced nuclear reaction is an important part of the interaction between neutron and matter,covering the basic science of nuclear fundamental physics,nuclear astrophysics,biology,material science and other important frontier disciplines,and also has a relatively wide range of applications in production and life,health and medical therapy.The advanced neutron science center is under construction with the efforts of building a platform supporting mult-functions neutron research in China.China has set up a Chinese spallation neutron source,which are used to perform a series of experiments for in-depth neutron research.The white neutron source takes the advantage of the back-n neutrons of China Spallation Neutron Source to carry out the fine measurement of various neutron reaction cross sections.Among the six spectrometers planned to be operated,the HPGe spectrometer makes full use of the measurement of the prompt y-ray to obtain the cross-section nuclear reaction data.The electronic system of HPGe spectrometer adopts precise waveform digitization technology,precise timing and time measurement technology and high-performance data readout technology to realize multi-channel,high-energy and high-time accuracy measurement and data readout of spectrometer.In this paper,the synchronization method of clock triggering in WNS HPGe spectrometer is proposed.Through the investigation of clock distribution and synchronization methods in large-scale physical experimental devices at home and abroad,the structural characteristics of each experimental facility and the global synchronous clock distribution method and trigger transmission scheme under different experimental requirements are analyzed.Combined with the structural characteristics and measurement requirements of the electronic system of HPGe spectrometer,this paper summarizes the design of the system.In order to realize the global synchronous clock distribution and trigger information transmission,the HPGe spectrometer electronic system adopts the chain topology structure,through high-precision timing and high-precision clock phase synchronization between the system nodes,so as to complete the global synchronous clock distribution and trigger synchronization.