Development of a Fast Visible Light Measurement System for the Study of Ion Cyclotron Range of Frequency Waves in GAMMA 10/PDX Plasmas

• EJIRI Akira

  The University of Tokyo

• HIRATA Mafumi

  University of Tsukuba

• ICHIMURA Makoto

  University of Tsukuba

• YOSHIKAWA Masayuki

  University of Tsukuba

• IKEZOE Ryuya

  Kyushu University

• KAMIO Shuji

  National Institute for Fusion Science

Abstract

A fast visible light measurement system was installed on GAMMA 10/PDX to measure plasma light fluctuations induced by ion cyclotron range of frequency (ICRF) (6360 kHz) waves. Time evolution and power spectrum were obtained and the relative amplitude of the fluctuations was the order of 0.1%. The difference of measured wavelength region was investigated by using three interference filters, but obtained time evolutions and the relative amplitudes were similar when we neglect a factor of difference. The RF pick-up noise is about two orders of magnitude smaller than the ICRF wave induced plasma signal, and the broad frequency band component is about an order of magnitude smaller than the signal. The latter arises from the shot-noise of the photon detection Poisson process, and an expression of the shot-noise, in which the effects of the frequency response of the system and the detector property are included, was obtained. The expression is confirmed experimentally using a stable light source.

Journal

• Plasma and Fusion Research

  Plasma and Fusion Research 16 (0), 1402096-1402096, 2021-09-17

  The Japan Society of Plasma Science and Nuclear Fusion Research

Keywords

• visible light measurement
• ICRF
• RF measurement
• mirror device
• Poisson process

Details

• CRID: 1390289475879556736
• NII Article ID: 130008091206
• DOI: 10.1585/pfr.16.1402096
• ISSN: 18806821
• Web Site: https://www.jstage.jst.go.jp/article/pfr/16/0/16_1402096/_pdf
• Text Lang: en
• Data Source:
  • JaLC
  • Crossref
  • CiNii Articles
  • KAKEN
• Abstract License Flag: Disallowed