The Effect of the Propagation Mode of a Laser Wave in an Interferometer Diagnostics in Determining of Electron Density of Damavand Tokamak Plasma and Calculation of the Measurement Error
Abstract
Interferometer is the one of tools to determine the plasma characteristics. In this paper, Firstly the regime of propagation mode for an infrared laser interferometer in plasma medium of Damavand tokamak is determined by considering the tokamak magnetic field range and the propagation angle. At the same time, the role of laser wavelength of diagnostic system in changing the propagation mode is examined. Results indicate, in a certain magnetic field, by increasing the laser wavelength the limitation of the quasi- longitudinal propagation mode becomes smaller, conversely that of the quasi-transverse propagation mode becomes larger. The introduced error in determining the refractive index with comparison between the refractive index of the ordinary mode and averaged refractive index from the Altar- Appleton- Hartree dispersion relation depends on the wave propagation angle and also the strength of the magnetic field. In a certain laser wavelength, increment of magnetic field increases the error value in phase measurement. On the other hand, in a specified magnetic field, by increasing of the laser wavelength, the error of phase measurement increases. Also, in a given propagation angle, by increasing the laser wavelength the error value in phase measurement significantly increases.
I. Pardon, “Interferometry: Research and applications in science and technology,” Second edition, 2016##
T. H. Stix, “Waves in plasmas,” American Institute of Physics, New York, 1992##
H. G. Booker, “Cold plasma waves,” Springer Netherlands, 1984##
H. G. Booker, “The Application of the Magneto-Ionic Theory to the Ionosphere,” Proceeding of the Royal Society of London, vol. 150A, pp. 267-276, 1935##
Y. Kawano, A. Nagashima, K. Tsuchiya, S. Gunji, S. Chiba, and T. Hatae, “Tangential CO2 laser interferometer for large tokamaks,” Journal of Plasma and Fusion Research, vol. 73, pp. 870-891, 1997##
P. M. Bellan, “Fundamentals of Plasma Physics,” Cambridge University Press, 2004##
M. Emami, A. R. Babazadeh, M. V. Roshan, M. Memarzadeh, and H. Habibi, “Digital control of plasma position in Damavand tokamak,” Brazilian Journal of Physics, vol. 32, no. 1, pp. 46-49, 2002##
P. Innocente, D. Mazon, E. Joffrin, and M. Riva, “Real- time fringe correction algorithm for the JET interferometer,” Review of Scientific Instruments 74, pp. 3645-3652, 2003##
G. Braithwaite, N. Gottardi, , G.Magyar, J. O’Rourke, J. Ryan, and D. Veron, “JET polari- interferometer,” Review of Scientific Instruments, vol. 60, pp. 2825-2834, 1989##
D. K. Mansfield, H. K. Park, L. C. Johnson, H. M. Anderson, R. Chouinard, V. S. Foote, C. H. Ma, and B. J. Clifton, “Multichannel far- infrared laser interferometer for electron density measurements on the tokamak fusion test reactor,” Applied Optics, vol. 26, no. 20, pp. 4469-4474, 1987##
T. Fukuda and A. Nagashima, “Frequency- stabilized single- mode cw 118.8 μm CH3OH waveguide laser for large tokamak diagnostics,” Review of Scientific Instruments, vol. 60, no. 6, pp. 1080-1085, 1989##
T. N. Carlstrom, D. R. Ahlgren, and J. Crosbie, “Real- time vibration- compensated CO2 interferometer operation on the DIII-D tokamak,” Review of Scientific Instruments, vol. 59, no. 7, pp. 1063-1066, 1988##
M. A. Van Zeeland, G. J. Kramer, R. Nazikian, H. L. Berk, T. N. Carlstrom, and W. M. Solomon, “Alfven eigenmode observations on DIII-D via two- colour CO2 interferometry,” Plasma Physics and Controled Fusion, vol. 47, pp. L31–L40, 2005##
V. S. Mukhovatov, “ITER operation and diagnostics,” Review of Scientific Instruments, vol. 61, no. 10, pp. 3241-3246, 1990##
X. Gao, H. J. Lu, Q. L. Guo, Y. X. Wan, and X. D. Tong, “Far- infrared laser diagnostics on the HT-6M tokamak”, Review of Scientific Instruments, vol. 66, no. 1, pp. 139-142, 1995##
S. Zhang, B. Wan, et al., “Application of far- infrared and millimeter wave techniques in plasma diagnostics in Hefei tokamaks”, IEEE, TU-F2, pp. 87-88, 2000##
J. Li, J. Luo, et al., “Quasi- steady- state ac plasma current operation in HT-7 tokamak,” Nuclear Fusion, vol. 47, no. 9, pp. 1071–1077, 2007##
Jie, Y. X., Gao, X., Cheng, Y. F., Yang, K., Tong, X. D. “Multi- channel FIR HCN laser interferometer on HT-7 tokamak,” International Journal of Infrared and Millimeter Waves, vol. 21, Issue 9, pp. 1375-1380, 2000##
I. H. Hutchinson, “Principles of plasma diagnostics,” Cambridge University Press, New York, 1992##
(2016). The Effect of the Propagation Mode of a Laser Wave in an Interferometer Diagnostics in Determining of Electron Density of Damavand Tokamak Plasma and Calculation of the Measurement Error. Applied Electromagnetics, 4(2), 47-53.
MLA
. "The Effect of the Propagation Mode of a Laser Wave in an Interferometer Diagnostics in Determining of Electron Density of Damavand Tokamak Plasma and Calculation of the Measurement Error". Applied Electromagnetics, 4, 2, 2016, 47-53.
HARVARD
(2016). 'The Effect of the Propagation Mode of a Laser Wave in an Interferometer Diagnostics in Determining of Electron Density of Damavand Tokamak Plasma and Calculation of the Measurement Error', Applied Electromagnetics, 4(2), pp. 47-53.
VANCOUVER
The Effect of the Propagation Mode of a Laser Wave in an Interferometer Diagnostics in Determining of Electron Density of Damavand Tokamak Plasma and Calculation of the Measurement Error. Applied Electromagnetics, 2016; 4(2): 47-53.
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