Refine your search:     
Report No.

Study on B$$_{4}$$C decoupler with burn-up reduction aiming at 1-MW pulsed neutron source

Oi, Motoki ; Teshigawara, Makoto  ; Harada, Masahide  ; Ikeda, Yujiro

In pulsed neutron sources, a neutron absorber called decoupler is attached to the moderator to sharpen the neutron pulses for achieving good neutron energy resolutions. Cadmium and boron carbide (B$$_{4}$$C) are widely used as the decoupler materials. However, it is difficult to use B$$_{4}$$C in MW-class spallation neutron sources owing to high burn-up, which decreases cut-off energy and increase of helium gas swelling. To solve these issues, we introduce the concept of pre-decoupler to reduce neutron absorption in the B$$_{4}$$C decoupler, which is sandwiched by appropriate neutron absorption materials. Then, we study impacts of the pre-decouplers on B$$_{4}$$C decoupler in terms of burn-up by performing simplified model calculations. It is shown that neutron absorption in B$$_{4}$$C is reduced by 60% by using a Cd pre-decoupler without neutron intensity penalty. Moreover, helium gas swelling in B$$_{4}$$C is restrained to be one-third of the value when not using the pre-decoupler.



- Accesses




Category:Nuclear Science & Technology



[CLARIVATE ANALYTICS], [WEB OF SCIENCE], [HIGHLY CITED PAPER & CUP LOGO] and [HOT PAPER & FIRE LOGO] are trademarks of Clarivate Analytics, and/or its affiliated company or companies, and used herein by permission and/or license.