title: Development of beam emission spectroscopy for turbulence transport study in Heliotron J.
abstract: This paper describes the development study of the beam emission spectroscopy (BES) for the turbulent transport study in Heliotron J. Modification of the sightlines (10 × 4 for edge and 10 × 2 for edge) enables us to obtain 2-dimensional BES imaging. The cooling effect on the reduction in the electrical noise of avalanche photodiode (APD) assembly has been investigated using a refrigerant cooling system. When the temperature of the APD element has set to be -20 °C, the electrical noise can be reduced more than 50%. The measurement error of the phase difference in the case of low signal level has been tested by two light-emitting diode lamps. The APD cooling has an effect to improve the measurement error at the low signal level of APD.
authors.affiliation: Institute of Advanced Energy, Kyoto University, Uji, Kyoto 611-0011, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Kobayashi
authors.affiliation: Institute of Advanced Energy, Kyoto University, Uji, Kyoto 611-0011, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Ohshima
authors.affiliation: Graduate School of Energy Science, Kyoto University, Uji, Kyoto 611-0011, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Matsuda
authors.affiliation: Graduate School of Energy Science, Kyoto University, Uji, Kyoto 611-0011, Japan.
authors.forename: X X
authors.initials: XX
authors.lastname: Lu
authors.affiliation: Graduate School of Energy Science, Kyoto University, Uji, Kyoto 611-0011, Japan.
authors.forename: D
authors.initials: D
authors.lastname: Kokubu
authors.affiliation: National Institute for Fusion Science, Oroshi-cho 322-6, Toki, Gifu 509-5292, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Ida
authors.affiliation: National Institute for Fusion Science, Oroshi-cho 322-6, Toki, Gifu 509-5292, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Kobayashi
authors.affiliation: National Institute for Fusion Science, Oroshi-cho 322-6, Toki, Gifu 509-5292, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Yoshinuma
authors.affiliation: Institute of Advanced Energy, Kyoto University, Uji, Kyoto 611-0011, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Kado
authors.affiliation: National Institute for Fusion Science, Oroshi-cho 322-6, Toki, Gifu 509-5292, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Oishi
authors.affiliation: Institute of Advanced Energy, Kyoto University, Uji, Kyoto 611-0011, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Nagasaki
authors.affiliation: Institute of Advanced Energy, Kyoto University, Uji, Kyoto 611-0011, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Okada
authors.affiliation: Institute of Advanced Energy, Kyoto University, Uji, Kyoto 611-0011, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Minami
authors.affiliation: Institute of Advanced Energy, Kyoto University, Uji, Kyoto 611-0011, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Yamamoto
authors.affiliation: Graduate School of Energy Science, Kyoto University, Uji, Kyoto 611-0011, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Nakamura
authors.affiliation: Graduate School of Energy Science, Kyoto University, Uji, Kyoto 611-0011, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Ishizawa
authors.affiliation: National Institute for Fusion Science, Oroshi-cho 322-6, Toki, Gifu 509-5292, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Kenmochi
authors.affiliation: Graduate School of Energy Science, Kyoto University, Uji, Kyoto 611-0011, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Otani
authors.affiliation: Institute of Advanced Energy, Kyoto University, Uji, Kyoto 611-0011, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Konoshima
authors.affiliation: Institute of Advanced Energy, Kyoto University, Uji, Kyoto 611-0011, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Mizuuchi