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Neoclassical transport processes in weakly collisional plasmas with fractured velocity distribution functions

Part of: Collisions in Collisionless Plasmas Focus on Fusion

Published online by Cambridge University Press:  15 September 2014

A. A. Kabantsev ,
C. F. Driscoll ,
D. H. E. Dubin  and
Yu. A. Tsidulko
A. A. Kabantsev*
Affiliation:
University of California at San Diego, La Jolla, CA 92093, USA
C. F. Driscoll
Affiliation:
University of California at San Diego, La Jolla, CA 92093, USA
D. H. E. Dubin
Affiliation:
University of California at San Diego, La Jolla, CA 92093, USA
Yu. A. Tsidulko
Affiliation:
Budker Institute of Nuclear Physics, Novosibirsk 630090, Russian Federation
*
†Email address for correspondence: [email protected]
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Abstract

Ripples in magnetic or electrostatic confinement fields give rise to trapping separatrices, and conventional neoclassical transport theory describes the collisional trapping/detrapping of particles with fractured distribution function. Our experiments and novel theory have now characterized a new kind of neoclassical transport processes arising from chaotic (nominally collisionless) separatrix crossings, which occur due to E × B plasma rotation along θ−ruffled or wave-perturbed separatrices. This chaotic neoclassical transport becomes dominant at low collisionality when the collisional spreading of particle energy during the dynamical period is less than the separatrix energy ruffle.

Type
Research Article
Information
Journal of Plasma Physics , Volume 81 , Issue 1 , January 2015 , 305810105
Copyright
Copyright © Cambridge University Press 2014 

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References

REFERENCES

Beidler, C. D. et al. 2011 Benchmarking of the mono-energetic transport coefficients–-results from the international collaboration on neoclassical transport in stellarators (ICNTS). Nucl. Fusion 51 (7), 076001–28.17.CrossRefGoogle Scholar
Dubin, D. H. E. 2008 Theory and simulations of electrostatic field error transport. Phys. Plasmas 15 (7), 072112–26.CrossRefGoogle Scholar
Dubin, D. H. E., Driscoll, C. F. and Tsidulko, Yu. A. 2010 Neoclassical transport caused by collisionless scattering across an asymmetric separatrix. Phys. Rev. Lett. 105 (18), 185003–4.Google Scholar
Dubin, D. H. E. and Tsidulko, Yu. A. 2011 Neoclassical transport and plasma mode damping caused by collisionless scattering across an asymmetric separatrix. Phys. Plasmas 18 (6), 062114–17.Google Scholar
Eggleston, D. L. and O'Neil, T. M. 1999 Theory of asymmetry-induced transport in a non-neutral plasma. Phys. Plasmas 6 (7), 2699–2704.Google Scholar
Eggleston, D. L. and Williams, J. M. 2008 Magnetic field dependence of asymmetry-induced transport: a new approach. Phys. Plasmas 15 (3), 032305–6.CrossRefGoogle Scholar
Gilson, E. P. and Fajans, J. 2003 Quadrupole-induced resonant-particle transport in pure electron plasma. Phys. Rev. Lett. 90 (1), 015001–4.Google Scholar
Helander, P. and Sigmar, D. J. 2002 Collisional Transport in Magnetized Plasmas, Cambridge: Cambridge University Press.Google Scholar
Hilsabeck, T. J. and O'Neil, T. M. 2003 Trapped-particle diocotron modes. Phys. Plasmas 10 (9), 3492–3505.Google Scholar
Kabantsev, A. A. and Driscoll, C. F. 2002 Trapped-particle modes and asymmetry-induced transport in single-species plasmas. Phys. Rev. Lett. 89 (24), 245001–4.Google Scholar
Kabantsev, A. A. and Driscoll, C. F. 2006 Trapped-particle mediated collisional damping of nonaxisymmetric plasma waves. Phys. Rev. Lett. 97 (9), 095001–4.Google Scholar
Kabantsev, A. A., O'Neil, T. M., Tsidulko, Yu. A. and Driscoll, C. F. 2008 Resonant drift-wave coupling modified by non-linear separatrix dissipation. Phys. Rev. Lett. 101 (6), 065002–4.Google Scholar
Mynick, H. E. 1983 Effect of collisionless detrapping on non-axisymmetric transport in a stellarator with radial electric field. Phys. Fluids 26 (9), 2609–2615.Google Scholar
Ohkawa, T., Gilleland, J. R. and Tamano, T. 1972 Observation of neoclassical, intermediate, and Pfirsch-Schulter diffusion in the dc octople. Phys. Rev. Lett. 28 (17), 1107–1111.Google Scholar
Pedrosa, M. A., Alonso, J. A., Garcéa-Regaña, J. M., Hidalgo, C., Velasco, J. L., Calvo, I. Silva, C., Helander, P. Electrostatic potential variations along flux surfaces in stellarators. arXiv:1404.0932.Google Scholar
Rosenbluth, M. N., Ross, D. W. and Kostomarov, D. P. 1972 Stability regions of dissipative trapped-ion instability. Nucl. Fusion 12 (1), 3–37.CrossRefGoogle Scholar
Zarnstorff, M. C. et al. 1990 Parallel electric resistivity in the TFTR tokamak. Phys. Fluids B 2 (8), 1852–1857.CrossRefGoogle Scholar