Hostname: page-component-cd9895bd7-gvvz8 Total loading time: 0 Render date: 2024-12-27T04:59:43.007Z Has data issue: false hasContentIssue false

A Code that Simulates Fast-Ion Dα and Neutral Particle Measurements

Published online by Cambridge University Press:  20 August 2015

W. W. Heidbrink*
Affiliation:
Department of Physics and Astronomy, University of California, Irvine, California, CA 92697, USA
D. Liu*
Affiliation:
Department of Physics and Astronomy, University of California, Irvine, California, CA 92697, USA Department of Physics, University of Wisconsin-Madison, Madison, WI53706, USA
Y. Luo*
Affiliation:
Department of Physics and Astronomy, University of California, Irvine, California, CA 92697, USA Tri Alpha Energy Corporation, 27211 Burbank, Foothill Ranch, CA 92610, USA
E. Ruskov*
Affiliation:
Department of Physics and Astronomy, University of California, Irvine, California, CA 92697, USA
B. Geiger*
Affiliation:
Max-Planck Institute für Plasmaphysik, Garching, Germany
Get access

Abstract

A code that models signals produced by charge-exchange reactions between fast ions and injected neutral beams in tokamak plasmas is described. With the fast-ion distribution function as input, the code predicts the efflux to a neutral particle analyzer (NPA) diagnostic and the photon radiance of Balmer-alpha light to a fast-ion Dα (FIDA) diagnostic. Reactions with both the primary injected neutrals and with the cloud of secondary “halo” neutrals that surround the beam are treated. Accurate calculation of the fraction of neutrals that occupy excited atomic states (the collisional-radiative transition equations) is an important element of the code. Comparison with TRANSP output and other tests verify the solutions. Judicious selection of grid size and other parameters facilitate efficient solutions. The output of the code has been validated by FIDA measurements on DIII-D but further tests are warranted.

Type
Research Article
Copyright
Copyright © Global Science Press Limited 2011

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

[1]Hutchinson, I. H., Principles of Plasma Diagnostics, Cambridge University Press, New York, 1987.Google Scholar
[2]Artsimovich, L. A., Afrostimov, V. V. and Gladkovskij, I. P.et al., in Plasma Physics and Controlled Nuclear Fusion Research 1965, Volume 2, pp. 595, Vienna, 1966, IAEA.Google Scholar
[3]Heidbrink, W. W., Burrell, K. H., Luo, Y., Pablant, N. A. and Ruskov, E., Hydrogenic fast-ion diagnostic using Balmer-alpha light, Plasma. Phys. Control. Fusion., 46 (2004), 1855–1875.Google Scholar
[4]Heidbrink, W. W., Fast-ion Dα measurements of the fast-ion distribution (invited), Rev. Sci. Instrum., 81 (2010), 10D727.CrossRefGoogle ScholarPubMed
[5]Heidbrink, W. W., Luo, Y. and Burrell, K. H.et al., Measurements of fast-ion acceleration at cyclotron harmonics using Balmer-alpha spectroscopy, Plasma. Phys. Control. Fusion., 49 (2007), 1457–1475.Google Scholar
[6]Egedal, J. and Bindslev, H., Reconstruction of gyrotropic phase-space distributions from 1D projections, Phys. Plasma., 11 (2004), 2191–2198.Google Scholar
[7]Salewski, M., Meo, F. and Stejner, M.et al., Comparison of fast-ion collective Thomson scattering measurements at ASDEX upgrade with numerical simulations, Nucl. Fusion., 50 (2010), 035012.Google Scholar
[8]Pankin, A., Mccune, D., Andre, R., Bateman, G. and Kritz, A., The tokamak Monte Carlo fast-ion module NUBEAM in the national transport code collaboration library, Comput. Phys. Commun., 159 (2004), 157–184.Google Scholar
[9]Budny, R. V., A standard DT supershot simulation, Nucl. Fusion., 34 (1994), 1247,CrossRefGoogle Scholar
[10]Lao, L. L., John, H.St., Stambaugh, R. D., Kellman, A. G. and Pfeiffer, W., Reconstruction of current profile parameters and plasma shapes in tokamaks, Nucl. Fusion., 25 (1985), 1611–1622.Google Scholar
[11]Chan, V. S., Chiu, S. C. and Omelchenko, Y. A., Radio-frequency-driven radial current and plasma rotation in a tokamak, Phys. Plasma., 9 (2002), 501–510.Google Scholar
[12]Harvey, R. W. and Mccoy, M. G., The CQL3D Fokker-Planck code, in Proceedings of IAEA Technical Committee Meeting on Advances in Simulation and Modeling of Thermonuclear Plasmas, Montreal, 1992, IAEA.Google Scholar
[13]Liu, D., Heidbrink, W. W. and Podesta, M.et al., Profiles of fast ions that are accelerated by high harmonic fast waves in the national spherical torus experiment, Plasma. Phys. Control. Fusion., 52 (2010), 025006.CrossRefGoogle Scholar
[14]Gianakon, T. A., Fonck, R. J., Callen, J. D., Durst, R. D. and Kim, J. S., Effects of edge plasma turbulence on radial correlation length measurements with BES, Rev. Sci. Instrum., 63 (1992), 4931–4933.CrossRefGoogle Scholar
[15]Hutchinson, I. H., Excited-state populations in neutral beam emission, Plasma. Phys. Control. Fusion., 44 (2002), 71–84.Google Scholar
[16]Series, G. W., The Spectrum of Atomic Hydrogen, Oxford University Press, New York, 1987.Google Scholar
[17]Press, W. H., Teukolsky, S. A., Vetterling, W. T. and Flannery, B. P., Numerical Recipes: The Art of Scientific Computing, Cambridge.Google Scholar
[18]Mandl, W., Development of active Balmer-alpha spectroscopy at JET, Technical Report JET-IR(92)05, JET, 1992.Google Scholar
[19]Van Zeeland, M. A., Heidbrink, W. W. and Yu, J., Fast-ion Dα imaging in the DIII-D tokamak, Plasma. Phys. Control. Fusion., 51 (2009), 055001.CrossRefGoogle Scholar
[21]Anderson, H., Von Hellermann, M. and Hoekstra, R.et al., Neutral beam stopping and emission in fusion plasmas I: deuterium beams, Plasma. Phys. Control. Fusion., 42 (2000), 781–806.CrossRefGoogle Scholar
[22]Janev, R. K., Boley, C. D. and Post, D. E., Penetration of energetic neutral beams into fusion plasmas, Nucl. Fusion., 29 (1989), 2125.Google Scholar
[23]Lodge, J. G., Percival, I. C. and Richards, D., Semi-empirical cross sections for excitation of hydrogen atoms by protons, J. Phys. B., 9 (1976), 239–254.Google Scholar
[24]Janev, R. K., Langer, W. D., Post, Jr. D. E. and Evans, Jr. K., Elementary Processes in Hydrogen-Helium Plasmas, Springer-Verlag, Berlin, 1987.Google Scholar
[25]Vriens, L. and Smeets, A. H. M., Cross-section and rate formulas for electron-impact ion-ization, excitation, deexcitation, and total depopulation of excited atoms, Phys. Rev. A., 22 (1980), 940–951.CrossRefGoogle Scholar
[26]Janev, R., Reiter, D. and Samm, U., Technical Report 4105, Juel Report, 2004, http://www.eirene.de.Google Scholar
[27]Bell, R. E., Carbon ion plume emission produced by charge exchange with neutral beams on NSTX, Technical Report PPPL-4167, Princeton Plasma Physics Laboratory, 2006.Google Scholar
[28]Finkenthal, D. F., The Measurement of Absolute Helium Ion Density Profiles on the DIII-D Tokamak Using Charge Exchange Recombination Spectroscopy, PhD thesis, University of California, Berkeley, 1994.Google Scholar
[29]Tang, V., Experimental and Numerical Characterization of Ion-cyclotron Heated Protons on the Alcator C-Mod Tokamak, PhD thesis, Massachusetts Institute of Technology, 2006.Google Scholar
[30]Luo, Y., Heidbrink, W. W., Burrell, K. H., Kaplan, D. H. and Gohil, P., Measurement of the Dα spectrum produced by fast ions in DIII-D, Rev. Sci. Instrum., 78 (2007), 033505.Google Scholar
[31]Goldston, R. J. and Rutherford, P. H., Introduction to Plasma Physics, Institute of Physics Publishing, Bristol, 1995.CrossRefGoogle Scholar
[32]Zeeland, M. A.Van, Yu, J. H. and Brooks, N. H.et al., Active and passive spectroscopic imaging in the DIII-D tokamak, Plasma. Phys. Control. Fusion., 52 (2010), 045006.Google Scholar
[33]Grierson, B.et al., Nucl. Fusion, (2011), submitted.Google Scholar
[34]Luo, Y., Heidbrink, W. W., Ruskov, E., Burrell, K. H. and Solomon, W. M., Fast-ion Dα measurements and simulations in quiet plasmas, Phys. Plasmas., 14 (2007), 112503.Google Scholar
[35]Heidbrink, W. W., Murakami, M. and Park, J. M.et al., Beam-ion confinement for different injection geometries, Plasma. Phys. Control. Fusion., 51 (2009), 125001.Google Scholar
[36]Geiger, B.et al., Fast-ion Dα measurements at ASDEX upgrade, Plasma. Phys. Control. Fusion., 53 (2011), 065010.Google Scholar