Development of a compact vertical splitting system for the cold neutron beam at JRR-3

International Workshop on Neutron Optics and Detectors

Tamura, I.^1 ; Maruyama, R.^2 ; Yamazaki, D.^2 ; Nakamura, K.^1 ; Yamamoto, K.^3 ; Aizawa, K.^2 ; Soyama, K.^2

Department of Research Reactor and Tandem Accelerator, Nuclear Science Research Institute, Tokai Research and Development Center, Tokyo, Ibaraki 319-1195, Japan^1

J-PARC Center, Japan Atomic Energy Agency, Tokyo, Ibaraki 319-1195, Japan^2

Nuclear Human Resource Development Center, Japan Atomic Energy Agency, Tokyo, Ibaraki 319-1195, Japan^3

关键词: Activation method;    Cold neutron beams;    Deflection angles;    Downstream region;    Neutron guides;    Radius of curvature;    Silicon substrates;    Vertical splitting;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/528/1/012012/pdf
DOI  :  10.1088/1742-6596/528/1/012012

来源: IOP

【 摘 要 】

In order to efficiently execute neutron beam experiments at JRR-3, the number of beam ports was increased and neutron beam instruments were rearranged in the C2 cold neutron beam line by using a newly developed compact vertical splitting system. Considering the space available for instruments at the downstream region of the cold neutron beam line, the deflection angles of the compact vertical splitting system were set as 10° and 20°. To branch off the cold neutron beam, a bender with characteristic wavelength of 4 A was developed using Ni/Ti supermirrors coated on both sides of 0.2-mm-thickness silicon substrates. The channel width of the bender is 0.2 mm. The radius of curvature of the compact bender is 938 mm and the lengths of the benders are 160mm and 320 mm, yielding deflection angles of 10° and 20°, respectively. Neutron flux at the end of the neutron guide installed at the bender exit, the deflection angle of which is 20°, was measured to be 1.58 x107n·cm-2·s-1with a gold foil activation method. We found that the measured flux agrees with the simulated value.