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Spatial inhomogeneity effects on burst temperature estimation using a triple probe configuration in Tokamak Chauffage Alfvén Brésilien tokamak

  • W. A. Hernandez (a1) (a2) (a3), Z. O. Guimarães-Filho (a1), G. G. Grenfell (a1) (a4) and I. C. Nascimento (a1)

Abstract

The effects of coherent structures in plasma edge turbulence are an important topic in the study of plasma cross-field transport in magnetically confined plasmas. To properly characterize these structures, their temperature must be measured, which is often done by using Langmuir probes. In this work, the techniques of Langmuir sweep and triple probe are used, considering the effect of plasma sheath expansion in both methods. It is shown that if the sheath expansion is ignored, the triple probe technique gives overestimated temperature values. In addition, the conditional analysis is applied to both techniques in order to evaluate the mean temperature time trace of the coherent structures. It is shown that these time traces can be distorted in the case of the triple probe technique, due to fact that coherent structures destroy the homogeneity condition on the pins array. Therefore, the sweep technique with a conditional selection of points is more suitable than the triple probe to study coherent structures related to bursts, as it performs a local measurement.

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Corresponding author

Email address for correspondence: ahernand@if.usp.br

References

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Adámek, J., Stöckel, J., Hron, M., Ryszawy, J., Tichý, M., Schrittwieser, R., Ionita, C., Balan, P., Martines, E. & Oost, G. V. 2004 A novel approach to direct measurement of the plasma potential. Czech. J. Phys. 54 (S3), C95C99.
Antar, G. Y., Counsell, G., Yu, Y., Labombard, B. & Devynck, P. 2003 Universality of intermittent convective transport in the scrape-off layer of magnetically confined devices. Phys. Plasmas 10 (2), 419428.
Antar, G. Y., Devynck, P., Garbet, X. & Luckhardt, S. C. 2001a Turbulence intermittency and burst properties in tokamak scrape-off layer. Phys. Plasmas 8 (5), 1612.
Antar, G. Y., Krasheninnikov, S. I., Devynck, P., Doerner, R. P., Hollmann, E. M., Boedo, J. A, Luckhardt, S. C. & Conn, R. W. 2001b Experimental evidence of intermittent convection in the edge of magnetic confinement devices. Phys. Rev. Lett. 87 (6), 065001.
Bittencourt, J. A. 2004 Fundamental of Plasma Physics. Springer.
Boedo, J. A., Gray, D., Conn, R. W., Luong, P., Schaffer, M., Ivanov, R. S., Chernilevsky, A. V., Van Oost, G. & Team, T. 1999 On the harmonic technique to measure electron temperature with high time resolution. Rev. Sci. Instrum. 70 (7), 29973006.
Budaev, V. & Ivanov, R. 1989 Correlative properties of edge plasma turbulence in tokamak TV-1. J. Nucl. Mater. 162–164, 322326.
Castro, R. & Heller, M. 1996 Temperature fluctuations and plasma edge turbulence in the Brazilian tokamak TBR. Phys. Plasmas 3 (March), 971977.
Chen, S.-L. & Sekiguchi, T. 1965 Instantaneous direct-display system of plasma parameters by means of triple probe. J. Appl. Phys. 36 (8), 2363.
Desideri, D. & Serianni, G. 1998 Four parameter data fit for Langmuir probes with nonsaturation of ion current. Rev. Sci. Instrum. 69 (6), 23542356.
Dimitrova, M., Popov, T. K., Adamek, J., Kovačič, J., Ivanova, P., Hasan, E., López-Bruna, D., Seidl, J., Vondráček, P., Dejarnac, R. et al. 2017 Plasma potential and electron temperature evaluated by ball-pen and Langmuir probes in the COMPASS tokamak. Plasma Phys. Control. Fusion 59 (12), 125001.
D’Ippolito, D. A., Myra, J. R. & Zweben, S. J. 2011 Convective transport by intermittent blob-filaments: comparison of theory and experiment. Phys. Plasmas 18 (6), 060501.
Gatsonis, N. A, Byrne, L. T., Zwahlen, J. C., Pencil, E. J. & Kamhawi, H. 2004 Current-mode triple and quadruple Langmuir probe methods with applications to flowing pulsed plasmas. IEEE Trans. Plasma Sci. 32 (5), 21182129.
Ghosh, S., Barada, K. K., Chattopadhyay, P. K., Ghosh, J. & Bora, D. 2015 Resolving an anomaly in electron temperature measurement using double and triple Langmuir probes. Plasma Sources Sci. Technol. 24 (1), 015017.
Guimarães-Filho, Z. O., Caldas, I. L., Viana, R. L., Heller, M. V. A. P., Nascimento, I. C., Kuznetsov, Y. K. & Bengtson, R. D. 2008 Electrostatic turbulence driven by high magnetohydrodynamic activity in Tokamak Chauffage Alfén Brésilien. Phys. Plasmas 15 (6), 062501.
Gunn, J. P., Boucher, C., Stansfield, B. L. & Savoie, S. 1995 Flush-mounted probes in the divertor plates of Tokamak de Varennes. Rev. Sci. Instrum. 66 (1), 154159.
Horton, W., Perez, J. C., Carter, T. & Bengtson, R. 2005 Vorticity probes and the characterization of vortices in the Kelvin–Helmholtz instability in the large plasma device experiment. Phys. Plasmas 12 (2), 022303.
Hussain, A. K. M. F. 1983 Coherent structures reality and myth. Phys. Fluids 26 (10), 2816.
Hutchinson, I. H. 2002 Principles of Plasma Diagnostics, 2nd edn. Cambridge University Press.
Johnsen, H., Pecseli, H. L. & Trulsen, J. 1986 Conditional eddies in plasma turbulence. Plasma Phys. Control. Fusion 28 (9B), 15191523.
Laux, M. 2001 Application of triple Probes to Magnetized Plasmas. Contrib. Plasma Phys. 41 (5), 510516.
Nagashima, Y., Inagaki, S., Fujisawa, A., Arakawa, H. & Yamada, T. 2015 Observation of parallel force balance for drift wave fluctuation by a fast voltage sweeping method in a linear plasma. J. Phys. Soc. Japan 063501, 1012.
Nascimento, I. C., Kuznetsov, Y., Guimarães-Filho, Z. O., Chamaa-Neto, I. E., Usuriaga, O., Fonseca, A. M. M., Galvão, R. M. O., Caldas, I. L., Severo, J. H. F., Semenov, I. B. et al. 2007 Suppression and excitation of MHD activity with an electrically polarized electrode at the TCABR tokamak plasma edge. Nucl. Fusion 47 (11), 1570.
Nielsen, A. H., Rasmussen, J. J., Madsen, J., Xu, G. S., Naulin, V., Olsen, J. M. B., Løiten, M., Hansen, S. K., Yan, N., Tophøj, L. et al. 2017 Numerical simulations of blobs with ion dynamics. Plasma Phys. Control. Fusion 59 (2), 025012.
Nold, B. & Holzhauer, E.2012 Electronic issues of Langmuir probe measurements on the midplane manipulator of ASDEX Upgrade. Tech. Rep.
Nold, B., Ribeiro, T. T., Ramisch, M., Huang, Z., Müller, H. W., Scott, B. D. & Stroth, U. 2012 Influence of temperature fluctuations on plasma turbulence investigations with Langmuir probes. New J. Phys. 14 (6), 063022.
Ogram, G. L., Chang, J.-S. & Hobson, R. M. 1979 The triple-probe method applied to the direct display of plasma parameters in a supersonic flowing continuum plasma. J. Appl. Phys. 50 (2), 726.
Pereira, F. A. C., Hernandez, W. A., Toufen, D. L., Guimarães-Filho, Z. O., Caldas, I. L. & Gentle, K. W. 2018 Burst temperature from conditional analysis in Texas Helimak and TCABR tokamak. Phys. Plasmas 25 (4), 042301.
Podestà, M., Fasoli, A., Labit, B., Furno, I., Ricci, P., Poli, F. M., Diallo, A., Müller, S. H. & Theiler, C. 2008 Cross-field transport by instabilities and blobs in a magnetized toroidal plasma. Phys. Rev. Lett. 101 (4), 045001.
Qayyum, A., Ahmad, S., Ahmad, N., Deeba, F. & Hussain, S. 2015 Triple probe measurements in transient plasma of pulsed capacitive discharge. J. Fusion Energy 34 (2), 405410.
Ross, D. W. 1992 On standard forms for transport equations and quasilinear fluxes. Plasma Phys. Control. Fusion 34 (2), 137146.
Spolaore, M., Vianello, N., Furno, I., Carralero, D., Agostini, M., Alonso, J. A., Avino, F., Cavazzana, R., De Masi, G., Fasoli, A. et al. 2015 Electromagnetic turbulent structures: a ubiquitous feature of the edge region of toroidal plasma configurations. Phys. Plasmas 22 (1), 012310.
Theiler, C., Furno, I., Kuenlin, a, Marmillod, P. & Fasoli, a 2011 Practical solutions for reliable triple probe measurements in magnetized plasmas. Rev. Sci. Instrum. 82 (1), 013504.
Theiler, C., Furno, I., Ricci, P., Fasoli, A., Labit, B., Muller, S. H. & Plyushchev, G. 2009 Cross-field motion of plasma blobs in an open magnetic field line configuration. Phys. Rev. Lett. 103 (6), 25.
Toufen, D. L., Pereira, F. A. C., Guimarães-Filho, Z. O., Caldas, I. L. & Gentle, K. W. 2014 Electrostatic turbulence intermittence driven by biasing in Texas Helimak. Phys. Plasmas 21 (12), 122302.
Weinlich, M. & Carlson, A. 1997 Flush mounted Langmuir probes in an oblique magnetic field. Phys. Plasmas 4 (6), 2151.
Zweben, S. J. 1985 Search for coherent structure within tokamak plasma turbulence. Phys. Fluids 28 (3), 974.
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