Abstract
CSNS (China Spallation Neutron Source) is a large scientific facility under construction, aiming for multidisciplinary research, which will be completed in early 2018. Taking the high proton power of 100 kW at Phase-I and 500 kW at Phase-II, it is also advantageous to add a white neutron beamline for nuclear data measurements in the facility. Study shows that the back-streaming neutrons at the spallation target have the typical characteristics as a white neutron beam, very intense flux of 107 n/cm2/s at a flight distance of 50 m, very wide energy spectrum of ev to 100 MeV, good time resolution of 1 ns to tens ns. A project (CSNS Back-n) to use the back-streaming neutrons for nuclear data measurements has been proposed and gets supported by a consortium of five institutions. The CSNS Back-n beamline has two endstations, at 50 m and 80 m from the target, respectively. The time resolution at 80 m can reach a few per mille in most cases, and special CSNS operation modes have been designed to obtain a best resolution of 1.5 per mille for the whole energy range. Six spectrometers including multi-layer fission chamber, BaF2 array for neutron capture, HPGe array, Light-particle emission measurement spectrometer, Prompt-fission neutron spectrum measurement spectrometer and total cross-section measurement spectrometer have been designed and will be built. Among them, four spectrometers will be available for experiments in late 2017 when the CSNS spallation target receives the first proton beam.
Coffee and tea will be served 20 minutes prior to the seminar.
Anyone interested is welcome to attend.