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Title: Observation of a new high-β and high-density state of a magnetospheric plasma in RT-1

Abstract

A new high-β and high-density state is reported for a plasma confined in a laboratory magnetosphere. In order to expand the parameter regime of an electron cyclotron resonance heating experiment, the 8.2 GHz microwave power of the Ring Trap 1 device has been upgraded with the installation of a new waveguide system. The rated input power launched from a klystron was increased from 25 to 50 kW, which enabled the more stable formation of a hot-electron high-β plasma. The diamagnetic signal (the averaged value of four magnetic loops signals) of a plasma reached 5.2 mWb. According to a two-dimensional Grad-Shafranov analysis, the corresponding local β value is close to 100%.

Authors:
; ; ; ; ; ; ;  [1]
  1. Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561 (Japan)
Publication Date:
OSTI Identifier:
22304444
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 21; Journal Issue: 8; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; DENSITY; ECR HEATING; KLYSTRONS; MICROWAVE RADIATION

Citation Formats

Saitoh, H., Yano, Y., Yoshida, Z., Nishiura, M., Morikawa, J., Kawazura, Y., Nogami, T., and Yamasaki, M. Observation of a new high-β and high-density state of a magnetospheric plasma in RT-1. United States: N. p., 2014. Web. doi:10.1063/1.4893137.
Saitoh, H., Yano, Y., Yoshida, Z., Nishiura, M., Morikawa, J., Kawazura, Y., Nogami, T., & Yamasaki, M. Observation of a new high-β and high-density state of a magnetospheric plasma in RT-1. United States. doi:10.1063/1.4893137.
Saitoh, H., Yano, Y., Yoshida, Z., Nishiura, M., Morikawa, J., Kawazura, Y., Nogami, T., and Yamasaki, M. Fri . "Observation of a new high-β and high-density state of a magnetospheric plasma in RT-1". United States. doi:10.1063/1.4893137.
@article{osti_22304444,
title = {Observation of a new high-β and high-density state of a magnetospheric plasma in RT-1},
author = {Saitoh, H. and Yano, Y. and Yoshida, Z. and Nishiura, M. and Morikawa, J. and Kawazura, Y. and Nogami, T. and Yamasaki, M.},
abstractNote = {A new high-β and high-density state is reported for a plasma confined in a laboratory magnetosphere. In order to expand the parameter regime of an electron cyclotron resonance heating experiment, the 8.2 GHz microwave power of the Ring Trap 1 device has been upgraded with the installation of a new waveguide system. The rated input power launched from a klystron was increased from 25 to 50 kW, which enabled the more stable formation of a hot-electron high-β plasma. The diamagnetic signal (the averaged value of four magnetic loops signals) of a plasma reached 5.2 mWb. According to a two-dimensional Grad-Shafranov analysis, the corresponding local β value is close to 100%.},
doi = {10.1063/1.4893137},
journal = {Physics of Plasmas},
number = 8,
volume = 21,
place = {United States},
year = {Fri Aug 15 00:00:00 EDT 2014},
month = {Fri Aug 15 00:00:00 EDT 2014}
}
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