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arXiv · 2106.13247

Construction and Commissioning of Mid-Infrared SASE FEL at cERL

Yosuke Honda·Masahiro Adachi·Shu Eguchi·Masafumi Fukuda·Ryoichi Hajima·Nao Higashi·Masayuki Kakehata·Ryukou Kato·Takako Miura·Tsukasa Miyajima·Shinya Nagahashi·Norio Nakamura·Kazuyuki Nigorikawa·Takashi Nogami·Takashi Obina·Hidenori Sagehashi·Hiroshi Sakai·Tadatake Sato·Miho Shimada·Tatsuro Shioya·Ryota Takai·Olga Tanaka·Yasunori Tanimoto·Kimichika Tsuchiya·Takashi Uchiyama·Akira Ueda·Masahiro Yamamoto·Hidehiko Yashiro·Demin Zhou
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Abstract

The mid-infrared range is an important spectrum range where materials exhibit a characteristic response corresponding to their molecular structure. A free-electron laser (FEL) is a promising candidate for a high-power light source with wavelength tunability to investigate the nonlinear response of materials. Although the self-amplification spontaneous emission (SASE) scheme is not usually adopted in the mid-infrared wavelength range, it may have advantages such as layout simplicity, the possibility of producing a single pulse, and scalability to a short-wavelength facility. To demonstrate the operation of a mid-infrared SASE FEL system in an energy recovery linac (ERL) layout, we constructed an SASE FEL setup in cERL, a test facility of the superconducting linac with the ERL configuration. Despite the adverse circumstance of space charge effects due to the given boundary condition of the facility, we successfully established the beam condition at the undulators, and observed FEL emission at a wavelength of 20 $\mu$m. The results show that the layout of cERL has the potential for serving as a mid-infrared light source.

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Yosuke Honda, Masahiro Adachi, Shu Eguchi, Masafumi Fukuda, Ryoichi Hajima, Nao Higashi, Masayuki Kakehata, Ryukou Kato, Takako Miura, Tsukasa Miyajima, Shinya Nagahashi, Norio Nakamura, Kazuyuki Nigorikawa, Takashi Nogami, Takashi Obina, Hidenori Sagehashi, Hiroshi Sakai, Tadatake Sato, Miho Shimada, Tatsuro Shioya, Ryota Takai, Olga Tanaka, Yasunori Tanimoto, Kimichika Tsuchiya, Takashi Uchiyama, Akira Ueda, Masahiro Yamamoto, Hidehiko Yashiro, Demin Zhou. 2021-06-24. Construction and Commissioning of Mid-Infrared SASE FEL at cERL. https://doi.org/10.1063/5.0072511

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