Present status of JAEA-Tokai tandem accelerator

Matsuda, Makoto  ; Kabumoto, Hiroshi  ; Tayama, Hidekazu; Nakanoya, Takamitsu  ; Nakamura, Masahiko; Kutsukake, Kenichi ; Otokawa, Yoshinori  ; Asozu, Takuhiro  ; Matsui, Yutaka; Ishizaki, Nobuhiro  ; Osa, Akihiko  

The JAEA-Tokai tandem accelerator was operated over a total of 64 days, and delivered 13 different ions to the experiments in the research fields of nuclear physics, nuclear chemistry, atomic physics, solid state physics and radiation effects in material in FY2017. After the vacuum accident occurred in December 2016 the accelerating voltage dropped to 12 MV. In order to remove dust and broken carbon foil in the accelerating tube, all 80 accelerator tubes were removed and rewashed. It took 4 months for cleaning and 2 months for reassembly. Therefore about 10 months were a maintenance period of an accelerator from February 2017. Along with the reconstruction of the accelerating tube, re-alignment of the accelerating tube was carried out. The operation resumed in December 2017 and it was possible to recover the maximum voltage to 17.4 MV without beam and 16.6 MV with beam with periodic conditioning work.