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arXiv · 2407.08925

Commissioning of a compact multibend achromat lattice: A new 3 GeV synchrotron radiation facility

Shuhei Obara·Kota Ueshima·Takao Asaka·Yuji Hosaka·Koichi Kan·Nobuyuki Nishimori·Toshitaka Aoki·Hiroyuki Asano·Koichi Haga·Yuto Iba·Akira Ihara·Katsumasa Ito·Taiki Iwashita·Masaya Kadowaki·Rento Kanahama·Hajime Kobayashi·Hideki Kobayashi·Hideo Nishihara·Masaaki Nishikawa·Haruhiko Oikawa·Ryota Saida·Keisuke Sakuraba·Kento Sugimoto·Masahiro Suzuki·Kouki Takahashi·Shunya Takahashi·Tatsuki Tanaka·Tsubasa Tsuchiyama·Risa Yoshioka·Tsuyoshi Aoki·Hideki Dewa·Takahiro Fujita·Morihiro Kawase·Akio Kiyomich·Takashi Hamano·Mitsuhiro Masaki·Takemasa Masuda·Shinichi Matsubara·Kensuke Okada·Choji Saji·Tsutomu Taniuchi·Yukiko Taniuchi·Yosuke Ueda·Hiroshi Yamaguchi·Kenichi Yanagida·Kenji Fukami·Naoyasu Hosoda·Miho Ishii·Toshiro Itoga·Eito Iwai·Tamotsu Magome·Masaya Oishi·Takashi Ohshima·Chikara Kondo·Tatsuyuki Sakurai·Masazumi Shoji·Takashi Sugimoto·Shiro Takano·Kazuhiro Tamura·Takahiro Watanabe·Takato Tomai·Noriyoshi Azumi·Takahiro Inagaki·Hirokazu Maesaka·Sunao Takahashi·Takashi Tanaka·Shinobu Inoue·Hirosuke Kumazawa·Kazuki Moriya·Kohei Sakai·Toshio Seno·Hiroshi Sumitomo·Ryoichi Takesako·Shinichiro Tanaka·Ryo Yamamoto·Kazutoshi Yokomachi·Masamichi Yoshioka·Toru Hara·Sakuo Matsui·Toshihiko Hiraiwa·Hitoshi Tanaka·Hiroyasu Ego
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Abstract

NanoTerasu, a new 3 GeV synchrotron light source in Japan, began user operation in April 2024. It provides high-brilliance soft to tender X-rays and covers a wide spectral range from ultraviolet to tender X-rays. Its compact storage ring with a circumference of 349 m is based on a four-bend achromat lattice to provide two straight sections in each cell for insertion devices with a natural horizontal emittance of 1.14 nm rad, which is small enough for soft X-rays users. The NanoTerasu accelerator incorporates several innovative technologies, including a full-energy injector C-band linear accelerator with a length of 110 m, an in-vacuum off-axis injection system, a four-bend achromat with B-Q combined bending magnets, and a TM020 mode accelerating cavity with built-in higher-order-mode dampers in the storage ring. This paper presents the accelerator machine commissioning over a half-year period and our model-consistent ring optics correction. The first user operation with a stored beam current of 160 mA is also reported. We summarize the storage ring parameters obtained from the commissioning. This is helpful for estimating the effective optical properties of synchrotron radiation at NanoTerasu.

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Shuhei Obara, Kota Ueshima, Takao Asaka, Yuji Hosaka, Koichi Kan, Nobuyuki Nishimori, Toshitaka Aoki, Hiroyuki Asano, Koichi Haga, Yuto Iba, Akira Ihara, Katsumasa Ito, Taiki Iwashita, Masaya Kadowaki, Rento Kanahama, Hajime Kobayashi, Hideki Kobayashi, Hideo Nishihara, Masaaki Nishikawa, Haruhiko Oikawa, Ryota Saida, Keisuke Sakuraba, Kento Sugimoto, Masahiro Suzuki, Kouki Takahashi, Shunya Takahashi, Tatsuki Tanaka, Tsubasa Tsuchiyama, Risa Yoshioka, Tsuyoshi Aoki, Hideki Dewa, Takahiro Fujita, Morihiro Kawase, Akio Kiyomich, Takashi Hamano, Mitsuhiro Masaki, Takemasa Masuda, Shinichi Matsubara, Kensuke Okada, Choji Saji, Tsutomu Taniuchi, Yukiko Taniuchi, Yosuke Ueda, Hiroshi Yamaguchi, Kenichi Yanagida, Kenji Fukami, Naoyasu Hosoda, Miho Ishii, Toshiro Itoga, Eito Iwai, Tamotsu Magome, Masaya Oishi, Takashi Ohshima, Chikara Kondo, Tatsuyuki Sakurai, Masazumi Shoji, Takashi Sugimoto, Shiro Takano, Kazuhiro Tamura, Takahiro Watanabe, Takato Tomai, Noriyoshi Azumi, Takahiro Inagaki, Hirokazu Maesaka, Sunao Takahashi, Takashi Tanaka, Shinobu Inoue, Hirosuke Kumazawa, Kazuki Moriya, Kohei Sakai, Toshio Seno, Hiroshi Sumitomo, Ryoichi Takesako, Shinichiro Tanaka, Ryo Yamamoto, Kazutoshi Yokomachi, Masamichi Yoshioka, Toru Hara, Sakuo Matsui, Toshihiko Hiraiwa, Hitoshi Tanaka, Hiroyasu Ego. 2024-07-12. Commissioning of a compact multibend achromat lattice: A new 3 GeV synchrotron radiation facility. https://doi.org/10.1103/physrevaccelbeams.28.020701

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