Temperature fluctuations and their correlation with density fluctuations in W7-AS
Correlations between electron density and temperature fluctuations have been measured in the core plasma of W7-AS. The simultaneous use of transmitting and receiving antennas of a heterodyne reflectom...
Correlations between electron density and temperature fluctuations have been measured in the core plasma of W7-AS. The simultaneous use of transmitting and receiving antennas of a heterodyne reflectom...
Electron cyclotron emission diagnostics on the large helical device
The electron cyclotron emission (ECE) diagnostic system is installed on the large helical device (LHD). The system includes the following instruments: a heterodyne radiometer, a Michelson spectrometer...
The electron cyclotron emission (ECE) diagnostic system is installed on the large helical device (LHD). The system includes the following instruments: a heterodyne radiometer, a Michelson spectrometer...
New electron cyclotron emission diagnostic for measurement of temperature based upon the electron Bernstein wave
Rev. Sci. Instrum. 70, 1018 (1999); doi:10.1063/1.1149464
Issue Date: January 1999
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Most magnetically confined plasma devices cannot take advantage of standard electron cyclotron emission (ECE) diagnostics to measure temperature. They either operate at high density relative to their magnetic field (e.g., 
p
c in spherical tokamaks) or they do not have sufficient density and temperature to reach the blackbody condition (
> 2). The standard ECE technique measures the electromagnetic waves emanating from the plasma. Here we propose to measure electron Bernstein waves (EBW) to ascertain the local electron temperature in these plasmas. The optical thickness of EBW is extremely high because it is an electrostatic wave with a large ki. For example, the National Spherical Torus Experiment (NSTX) will have an optical thickness ![[approximate]](http://scitation.aip.org/stockgif2/ap.gif)
3000 and CDX-U will have 300. One can reach the blackbody condition with a plasma density 1011 cm – 3 and Te1 eV. This makes it attractive to most plasma devices. The serious issue with using EBW is the wave accessibility for the emission measurement. Simple accessibility arguments indicate the wave may be accessible by either direct coupling or mode conversion through an extremely narrow layer (1–2 mm). EBW experiments on the Current Drive Experiment-Upgrade (CDX-U) will test the accessibility properties of the spherical tokamak configuration. ©1999 American Institute of Physics.
pc in spherical tokamaks) or they do not have sufficient density and temperature to reach the blackbody condition (> 2). The standard ECE technique measures the electromagnetic waves emanating from the plasma. Here we propose to measure electron Bernstein waves (EBW) to ascertain the local electron temperature in these plasmas. The optical thickness of EBW is extremely high because it is an electrostatic wave with a large ki. For example, the National Spherical Torus Experiment (NSTX) will have an optical thickness 3000 and CDX-U will have 300. One can reach the blackbody condition with a plasma density 1011 cm – 3 and Te1 eV. This makes it attractive to most plasma devices. The serious issue with using EBW is the wave accessibility for the emission measurement. Simple accessibility arguments indicate the wave may be accessible by either direct coupling or mode conversion through an extremely narrow layer (1–2 mm). EBW experiments on the Current Drive Experiment-Upgrade (CDX-U) will test the accessibility properties of the spherical tokamak configuration. ©1999 American Institute of Physics.
| History: | Presented 10 June 1998 |
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KEYWORDS and PACS
PLASMA WAVES,
PLASMA DIAGNOSTICS,
TEMPERATURE MEASUREMENT,
RADIOMETERS,
MAGNETIC FIELDS,
BERNSTEIN MODE,
radiometry,
plasma temperature,
plasma Bernstein waves,
plasma toroidal confinement
- 52.70.Gw
Physics of plasmas and electric discharges Plasma diagnostic techniques and instrumentation Radio-frequency and microwave measurements - 52.35.Hr
Physics of plasmas and electric discharges Waves, oscillations, and instabilities in plasma Electromagnetic waves (e.g., electron-cyclotron, Whistler, Bernstein, upper hybrid, lower hybrid) - 52.55.Fa
Physics of plasmas and electric discharges Magnetic confinement and equilibrium Tokamaks - 52.55.Pi
Physics of plasmas and electric discharges Magnetic confinement and equilibrium Fusion products effects (e.g., alpha-particles, etc.) - 07.57.Kp
Instruments, apparatus, components, and techniques common to several branches of physics and astronomy Infrared, submillimeter wave, microwave and radiowave instruments, equipment and techniques Bolometers; infrared, submillimeter wave, microwave, and radiowave receivers and detectors - YEAR: 1999
PUBLICATION DATA
0034-6748 (print)
1089-7623 (online)
AIP
REFERENCES (12)
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- M. Bornatici et al.,
Nucl. Fusion 23, 1153 (1983) . - H. J. Hartfuss et al.,
Plasma Phys. Controlled Fusion 39, 1693 (1997) . - A. E. Costley et al., Phys. Rev. Lett. 33, 758 (1974).
- D. A. Gates et al., Phys. Plasmas 5, 1775 (1998).
- J. Spitzer et al.,
Fusion Technol. 30, 1337 (1996) . - J. Hosea, V. Arunasalam, and R. Cano, Phys. Rev. Lett. 39, 408 (1977).
- G. Bekefi, Radiation Processes in a Plasma (Wiley, New York, 1966).
- T. H. Stix, The Theory of Plasma Waves (McGraw–Hill, New York, 1962).
- S. Bernabei et al., Phys. Rev. Lett. 34, 866 (1975).
- K. C. Wu, A. K. Ram, and A. Bers, Proc. Am. Phys. Soc. 41, 1425 (1996).
- H. P. Laqua et al., Phys. Rev. Lett. 78, 3467 (1997).
- M. Ono et al., Princeton Plasma Physics Lab Report No. 3225, 1997 (unpublished).
