Research On The Design Of LLRF System For RCS Of CSNS And Measurement Of RRR Value For Niobium

Neutron scattering technology is one of the most important tools for study of the microstructure and development of matters, which is widely used in the basic and applicative researches of Condensed matter physics, chemistry, biology engineering, material science, nanometer science and technology, Nuclear Physics, medical science etc. Neutron spallation source is such a big device where protons are first accelerated to the energy of GeV level, then bombard the heavy-metal target in order to generate neutrons. Its best strong-points are reliable security and high efficiency of neutron flux.The RCS (rapid cycling synchronous accelerator) LLRF (low level radio frequency) control system is the key point of the locking of the RF cavity resonance frequency and the RF signal frequency, which ensures that the biggest gap voltage will be attained by using the minimal RF power and the beam compensation for the cavity detuning to get the protons of required high energy. During my study time in IHEP (Institute of High Energy of Physics), I was involved in the prefab research of the RCS LLRF of CSNS (China Spallation Neutron Source). After the analysis of the present spallation neutron source RCS LLRF control system in the world like SNS in the US and J-PARC in Japan, combined with the features of our CSNS, an available design of controlling methods was brought forward.At the same time I also worked in the Beijing Superconductivity Lab in IHEP on the measurement of the RRR (Residual Resistance Ratio) value of superconductive material Niobium.