Design and Test of Collimator for Back-streaming White Neutron Source for CSNS

In order to provide required beam shape and lower experimental background for nuclear data measurement, the beam of back-streaming white neutron source should be collimated by collimator. Taking the shutter as an example, the overall design scheme was determined according to the relevant requirements. The problem of processing small diameter deep hole was solved by dividing the block into two parts. The contour and sealing system of the vacuum chamber were optimized by using the finite element analysis software. A high-precision radiation-resistant mobile platform was built, which can meet the requirements of high vacuum. After testing, the main technical indicators of the shutter meet the design requirements, and it shows that the design is reasonable.