Achievement of 200,000 hours of operation at KEK 7-GeV electron 4-GeV positron injector linac

Kazuro Furukawa; Mitsuo Akemoto; Dai Arakawa; Yoshio Arakida; Yusei Bando; Hiroyasu Ego; Yoshinori Enomoto; Toshiyasu Higo; Hiroyuki Honma; Naoko Iida; Kazuhisa Kakihara; Takuya Kamitani; Hiroaki Katagiri; Masato Kawamura; Shuji Matsumoto; Toshihiro Matsumoto; Hideki Matsushita; Katsuhiko Mikawa; Takako Miura; Fusashi Miyahara; Hiromitsu Nakajima; Takuya Natsui; Yujiro Ogawa; Satoshi Ohsawa; Yuichi Okayasu; Takao Oogoe; Muhammad Abdul Rehman; Itsuka Satake; Masanori Satoh; Yuji Seimiya; Tetsuo Shidara; Akihiro Shirakawa; Hirohiko Someya; Tsuyoshi Suwada; Madoka Tanaka; Di Wang; Yoshiharu Yano; Kazue Yokoyama; Mitsuhiro Yoshida; Takashi Yoshimoto; Rui Zhang; Xiangyu Zhou

doi:10.1088/1742-6596/2420/1/012021

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arXiv · 2207.01192

Achievement of 200,000 hours of operation at KEK 7-GeV electron 4-GeV positron injector linac

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Abstract

KEK electron positron injector LINAC initiated the injection operation into Photon Factory (PF) light source in 1982. Since then for 39 years, it has served for multiple projects, namely, TRISTAN, PF-AR, KEKB, and SuperKEKB. Its total operation time has accumulated 200 thousand hours on May 7, 2020. We are extremely proud of the achievement following continuous efforts by our seniors. The construction of the injector LINAC started in 1978, and it was commissioned for PF with 2.5 GeV electron in 1982. In parallel, the positron generator linac was constructed for the TRISTAN collider project. The slow positron facility was also commissioned in 1992. After the KEKB asymmetric-energy collider project was commissioned in 1998 with direct energy injections, the techniques such as two-bunch acceleration and simultaneous injection were developed. As the soft structure design of the LINAC was too weak against the great east Japan earthquake, it took three years to recover. Then the construction and commissioning for the SuperKEKB project went on, and the simultaneous top-up injection into four storage rings contributes to the both elementary particle physics and photon science.

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Kazuro Furukawa, Mitsuo Akemoto, Dai Arakawa, Yoshio Arakida, Yusei Bando, Hiroyasu Ego, Yoshinori Enomoto, Toshiyasu Higo, Hiroyuki Honma, Naoko Iida, Kazuhisa Kakihara, Takuya Kamitani, Hiroaki Katagiri, Masato Kawamura, Shuji Matsumoto, Toshihiro Matsumoto, Hideki Matsushita, Katsuhiko Mikawa, Takako Miura, Fusashi Miyahara, Hiromitsu Nakajima, Takuya Natsui, Yujiro Ogawa, Satoshi Ohsawa, Yuichi Okayasu, Takao Oogoe, Muhammad Abdul Rehman, Itsuka Satake, Masanori Satoh, Yuji Seimiya, Tetsuo Shidara, Akihiro Shirakawa, Hirohiko Someya, Tsuyoshi Suwada, Madoka Tanaka, Di Wang, Yoshiharu Yano, Kazue Yokoyama, Mitsuhiro Yoshida, Takashi Yoshimoto, Rui Zhang, Xiangyu Zhou. 2022-07-04. Achievement of 200,000 hours of operation at KEK 7-GeV electron 4-GeV positron injector linac. https://doi.org/10.1088/1742-6596%2F2420%2F1%2F012021

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