Dielectric tensor expression for non-Maxwellian distribution functions and applications to α-particle damping in ICRH

Abstract.The components of the dielectric tensor for the distribution function given by Leubner and Schupfer have been obtained. The effect of the loss-cone index appearing in the particle distribution function in a hot magnetized plasma has been studied. A case study has been performed to calculate temporal growth rates of Bernstein waves using the distribution function given by Summers and Thorne and Leubner and Schupfer. The effect of the loss-cone index on growth rates is found to be quite different for the two distribution functions.

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Effects of Landau Damping and Collision on Stimulated Raman Scattering with Various Phase-Space Distributions

Chinese Physics B ◽

10.1088/1674-1056/ac3ba7 ◽

2021 ◽

Author(s):

Shanxiu XIE ◽

Yong CHEN ◽

Junchen YE ◽

Yugu CHEN ◽

Na PENG ◽

...

Keyword(s):

Growth Rate ◽

Raman Scattering ◽

Stimulated Raman Scattering ◽

Deep Understanding ◽

Distribution Functions ◽

Maxwellian Distribution ◽

Landau Damping ◽

Hot Electron ◽

Collisional Damping ◽

Stimulated Raman

Abstract Stimulated Raman scattering (SRS) is one of the main instabilities affecting the success of the fusion ignition. Here, we study the relationship between Raman growth and Landau damping with various distribution functions combining the analytic formulas and Vlasov simulations. The Landau damping obtained by Vlasov-Poisson simulation and Raman growth rate obtained by Vlasov-Maxwell simulation are anti-correlated, which is consistent with our theoretical analysis quantitatively. Maxwellian distribution, flattened distribution, and bi-Maxwellian distribution are studied in detail, which represent three typical stages of SRS. We have also demonstrated the effects of plateau width, hot-electron fraction, hot-to-cold electron temperature ratio, and collisional damping on the Landau damping and growth rate. It gives us a deep understanding of SRS and possible ways to mitigate SRS through manipulating distribution functions to a high Landau damping regime.

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Weibel instability with non-Maxwellian distribution functions

Physics of Plasmas ◽

10.1063/1.2536159 ◽

2007 ◽

Vol 14 (2) ◽

pp. 022108 ◽

Cited By ~ 41

Author(s):

S. Zaheer ◽

G. Murtaza

Keyword(s):

Distribution Functions ◽

Maxwellian Distribution ◽

Weibel Instability

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Stability of Dense Stellar Clusters against Relativistic Collapse. II. Maxwellian Distribution Functions with Different Cutoff Parameters

The Astrophysical Journal ◽

10.1086/305689 ◽

1998 ◽

Vol 500 (1) ◽

pp. 217-232 ◽

Cited By ~ 10

Author(s):

G. S. Bisnovatyi‐Kogan ◽

M. Merafina ◽

R. Ruffini ◽

E. Vesperini

Keyword(s):

Distribution Functions ◽

Maxwellian Distribution ◽

Stellar Clusters ◽

Relativistic Collapse

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Weakly relativistic dielectric tensor in the presence of temperature anisotropy

Journal of Plasma Physics ◽

10.1017/s002237780001521x ◽

1990 ◽

Vol 44 (2) ◽

pp. 319-335 ◽

Cited By ~ 5

Author(s):

M. Bornatici ◽

G. Chiozzi ◽

P. de Chiara

Keyword(s):

Distribution Function ◽

Cyclotron Frequency ◽

Electron Cyclotron ◽

Maxwellian Distribution ◽

Larmor Radius ◽

Dielectric Tensor ◽

Temperature Anisotropy ◽

Finite Larmor Radius ◽

Maxwellian Distribution Function ◽

Analytical Expressions

Analytical expressions for the weakly relativistic dielectric tensor near the electron-cyclotron frequency and harmonies are obtained to any order in finite-Larmor-radius effects for a bi-Maxwellian distribution function. The dielectric tensor is written in ternis of generalized Shkarofsky dispersion functions, whose properties are well known. Relevant limiting cases are considered and, in particular, the anti-Hermitian part of the (fully relativistic) dielectric tensor is evaluated for two cases of strong temperature anisotropy.

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