Abstract
Back-streaming neutrons through the incoming proton channel at the spallation target station of China Spallation Neutron Source (CSNS) were exploited to build a white neutron beam line (the so-called Back-n). With a proton beam of 100 kW in beam power and 1.6 GeV in kinetic energy and a thick tungsten target and modest moderation by the cooling water through the target slices, the neutron beam is very intense which is in the order of 7.0×106 n/cm2/s at 77 m from the target and has an excellent energy spectrum spanning from 0.5 eV to 200 MeV. In addition, the time resolution related to the time-of-flight measurements is very good for neutron energy determination. Altogether, it makes the CSNS Back-n one of the best white neutron sources in the world and very suitable for nuclear data measurements, especially for neutron-induced cross-section measurements. Since the completion of the Back-n beamline and four physics spectrometers in March 2018, the first batches of experiments on nuclear data measurements have been carried out, which are summarized in this article.
Highlights
China Spallation Neutron Source (CSNS) is the largest scientific facility ever built in China, which was completed in March 2018 and serves mainly for multidisciplinary research on material characterization using neutron scattering techniques [1,2,3]
The earlier studies show that the back-streaming neutrons along the impinging proton beam channel from the spallation target have properties of a wide energy spectrum, very high flux and good time structure, which is very suitable to be exploited as a white neutron source for nuclear data measurements and other applications [4,5,6,7,8,9]
To fully exploit the capability of the Back-n white neutron beam, a number of physics spectrometers dedicated to different types of measurements were planned, and four of them were made available for experiments in 2018
Summary
China Spallation Neutron Source (CSNS) is the largest scientific facility ever built in China, which was completed in March 2018 and serves mainly for multidisciplinary research on material characterization using neutron scattering techniques [1,2,3]. Other planned spectrometers include: a new and larger 4 BaF2 array (GTAF-III) for neutron capture measurements, a detector array for prompt fission neutron spectrum measurements (PFNS), a 4 HPGe/LaBr3 detector array for gamma spectrum measurements (n, n /2n ), and a multi-function TPC (Time Projection Chamber) based spectrometer for measuring fission products and light charged particles. The first-year experiments on nuclear data measurements at the Back-n have been carried out very successfully
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
