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Generalized curvature modified plasma dispersion functions and Dupree renormalization of toroidal ITG [article]

Ö. Gültekin, Ö. D. Gürcan
2019 arXiv   pre-print
of the velocity, can be written entirely using generalized curvature modified plasma dispersion functions: Knm's.  ...  A new generalization of curvature modified plasma dispersion functions is introduced in order to express Dupree renormalized dispersion relations used in quasi-linear theory.  ...  A particular such generalization is the introduction of the so called curvature modified plasma dispersion functions.  ... 
arXiv:1711.11498v2 fatcat:jtl324haijesldhmchjbloun6e

Stable and unstable roots of ion temperature gradient driven mode using curvature modified plasma dispersion functions

Ö Gültekin, Ö D Gürcan
2018 Plasma Physics and Controlled Fusion  
This method requires computing the plasma dielectric function and its derivatives, which are implemented here using modified plasma dispersion functions with curvature and their derivatives, and allows  ...  We provide an open source implementation of the derivatives of modified plasma dispersion functions with curvature, which are used in this formulation.  ...  Recently, a similar, numerically efficient reformulation of local ITG in terms of curvature modified plasma dispersion functions was proposed [10] , which is equivalent to the formulation in Refs.  ... 
doi:10.1088/1361-6587/aa9e27 fatcat:5zp3sr3hhndwpgxiaicxgdn76q

Effects of local features of the equilibrium current density profile on linear tearing modes

F. Militello, G. Huysmans, M. Ottaviani, F. Porcelli
2004 Physics of Plasmas  
A new analytic dispersion relation is derived, which takes into account in a consistent way these new terms and which agrees very well with numerically computed growth rates.  ...  It is shown that local features of the equilibrium current density profile, i.e., its gradient and curvature evaluated at the resonant magnetic surface, can modify considerably the linear behavior of tearing  ...  Our work allows one to resolve the discrepancy that is sometimes observed between the dispersion relation ͑1͒ and numerical computations of tearing mode growth rates.  ... 
doi:10.1063/1.1632495 fatcat:m4rlxgpxkrb63lpfps7kev3yz4

Chiral Plasma Instabilities

Yukinao Akamatsu, Naoki Yamamoto
2013 Physical Review Letters  
We study the collective modes in relativistic electromagnetic or quark-gluon plasmas with an asymmetry between left- and right-handed chiral fermions, based on the recently formulated kinetic theory with  ...  We find that there exists an unstable mode, signaling the presence of a plasma instability.  ...  We show that the Berry curvature corrections dramatically modify the dispersion relation of the collective modes, and in particular, lead to unstable modes, signaling the presence of a plasma instability  ... 
doi:10.1103/physrevlett.111.052002 pmid:23952387 fatcat:43ugazaiczeovbcgeg73j6bd3a

Effects of magnetic curvature on the lower-hybrid-drift instability

Genta Ueno
2001 Physics of Plasmas  
A local dispersion relation is derived for the lower-hybrid-drift instability including the effects of magnetic curvature associated with transverse electromagnetic perturbations.  ...  The effects of the magnetic curvature become larger in high-beta plasmas.  ...  APPENDIX C: THE ALTERED PLASMA DISPERSION FUNCTION In the theory of linearized waves in a hot plasma with a zeroth order curved magnetic field, a certain function of complex argument, which we will call  ... 
doi:10.1063/1.1354646 fatcat:ccokjm6iyrg37h4jbjvmwqtgnq

An FDTD Model for Low and High Altitude Lightning-Generated EM Fields

W. Hu, S.A. Cummer
2006 IEEE Transactions on Antennas and Propagation  
A dispersive and anisotropic realization of the nearly perfectly matched layer (NPML) absorbing boundary condition is adopted in this numerical model for ease of implementation.  ...  Earth curvature is included in the model through the modified refractive index method. The surface impedance boundary condition is adopted to treat arbitrary but homogeneous ground parameters.  ...  Dispersion Analysis In a cold plasma with the presence of a static magnetic field, the dispersion relation is dependent on the wave propagation direction because the medium is anisotropic.  ... 
doi:10.1109/tap.2006.874336 fatcat:f2eu4kb6ybfhtmcimtsaiomsba

Electrostatic fluctuations in the Current Sustained Torus IV at Nagoya University

K. Zhai, M. Kobayashi, K. Tashiro, H. Kojima, M. Takagi, S. Takamura
2000 Physics of Plasmas  
Plasma Fusion Res. 74, 38 ͑1998͔͒ through measurement with an array of Langmuir probes. The observed statistical dispersion relation indicates a drift-wave-type turbulence.  ...  A detailed experimental investigation of plasma fluctuation and its modification due to radial electric field effects, both its shear and curvature, has been carried out on the Current Sustained Torus  ...  ACKNOWLEDGMENTS The authors gratefully acknowledge the useful discussion with Dr. Y. Uesugi and Dr. N. Ohno.  ... 
doi:10.1063/1.874084 fatcat:tphh5sfvurejpjjbmqyqsud2km

Toroidal curvature induced screening of external fields by a resistive plasma response

Yueqiang Liu, J. W. Connor, S. C. Cowley, C. J. Ham, R. J. Hastie, T. C. Hender
2012 Physics of Plasmas  
This numerical factor varies with the choice of plasma equilibria.  ...  The real and imaginary parts of the numerically computed plasma response (dots) and the least-square fits (lines) using the analytic relation (3), for a large aspect ratio equilibrium with finite plasma  ... 
doi:10.1063/1.4739062 fatcat:2cooh7jj3jerxecwhx5syxt6qq

Beta-induced Alfvén-acoustic eigenmodes in National Spherical Torus Experiment and DIII-D driven by beam ions

N. N. Gorelenkov, M. A. Van Zeeland, H. L. Berk, N. A. Crocker, D. Darrow, E. Fredrickson, G.-Y. Fu, W. W. Heidbrink, J. Menard, R. Nazikian
2009 Physics of Plasmas  
Gorelenkov et al., Plasma Phys. Controlled Fusion 49, B371 ͑2007͔͒. The kinetic theory is based on the ballooning dispersion relation where the drift frequency effects are retained.  ...  BAAEs deteriorate the fast ion confinement in DIII-D and can have a similar effect in next-step fusion plasmas, especially if excited together with multiple global toroidicity-induced shear Alfvén eigenmode  ...  Simple BAAE dispersion in electron dominated plasma, š 1 Kinetic dispersion of the modified Alfvén branch in a plasma with dominant electron beta corresponds to the limit Ͼ 2 i 2 ӷ 1.  ... 
doi:10.1063/1.3097920 fatcat:mbmql4b3wnbybowk6u7tmdkjf4

Collisionless and resistive ballooning stability

J. W. Connor, R. J. Hastie
1999 Physics of Plasmas  
Figure 2 shows the numerically computed stability boundary in terms of ZϭZ 0 /(⌬ B Ј G 5/6 ) ͑solid curve͒ as a function of ␦, compared to the approximate values ͑broken curve͒ obtained from inequality  ...  Solution of the dispersion relation numerically shows that the favorable average curvature stabilization of resistive tearing modes, discovered by Glasser et al., 7 persists in the inertial limit (m  ... 
doi:10.1063/1.873693 fatcat:ex4rpwwy4jc6rgwob6qxmjrtwm

Modes in a non-neutral plasma of finite length, m=0,1

S. Neil Rasband, Ross L. Spencer
2003 Physics of Plasmas  
For mϭ1 it is found that the eigenfrequencies are 2% to 3% higher than given by the Fine-Driscoll formula ͓Phys. Plasmas 5, 601 ͑1998͔͒. The "new modes" of Hilsabeck and O'Neil ͓Phys.  ...  , modes is calculated numerically.  ...  This is consistent with solutions inside the plasma proportional to the modified Bessel function I 1 in r and cosh(kz) in z, with k very small such that 1/k is much longer than the length of the confining  ... 
doi:10.1063/1.1559683 fatcat:3apwzjp7abdhfleymwumcbwjpm

Standing sausage modes in curved coronal slabs

D. J. Pascoe, V. M. Nakariakov
2016 Astronomy and Astrophysics  
We extend models of standing sausage modes in low β coronal loops to include the effects of loop curvature.  ...  The ratios of the periods of oscillations for different longitudinal harmonics depend on the dispersive nature of the waveguide and so may be used as a seismological tool to determine coronal parameters  ...  The computational work for this paper was carried out on the joint STFC and SFC (SRIF) funded cluster at the University of St Andrews (Scotland, UK).  ... 
doi:10.1051/0004-6361/201526546 fatcat:aw7ymqj77fe2xfffzvzgyy675u

Refining pulsar radio emission due to streaming instabilities: Linear theory and PIC simulations in a wide parameter range [article]

Alina C. Manthei, Jan Benáček, Patricio A. Muñoz, Jörg Büchner
2020 arXiv   pre-print
The growth rates obtained in dependence on background and beam densities, temperatures and streaming velocities showed a remarkable agreement of the linear dispersion predictions and numerical simulation  ...  We validate the analytical results by comparison with relativistic kinetic particle-in-cell (PIC) numerical simulations.  ...  Computational resources were also supplied by the project "e-Infrastruktura CZ" (e-INFRA LM2018140) provided within the program Projects of Large Research, Development and Innovations Infrastructures.  ... 
arXiv:2011.07377v1 fatcat:czqmfbcnazdvbeymfp4ys3hpnu

Surface plasmon polaritons in concentric cylindrical structures

J. Pritz, L.M. Woods
2008 Solid State Communications  
Numerical evaluations of the transcendental equation for the dispersion relation are given to analyze the role of factors such as number of shells, dielectric properties of the materials and the environment  ...  , curvature and size of the system.  ...  David Rabson (USF) for helping establish the computer code used for these calculations.  ... 
doi:10.1016/j.ssc.2008.01.039 fatcat:722ieh55k5aupcn733dpzco47u

Three-dimensional measurements of non-diffusive fast ion transport in TORPEX

A Bovet, I Furno, A Fasoli, K Gustafson, P Ricci
2013 Plasma Physics and Controlled Fusion  
In the basic plasma physics device TORPEX, progress in the fundamental understanding of supra-thermal ion transport is achieved by extensive sets of three-dimensional (3D) data, together with numerical  ...  A synthetic diagnostic allows comparing the experimental results with numerical simulations of the fast ion transport in a global fluid simulation of the TORPEX plasma. A good agreement is shown.  ...  Acknowledgments The authors would like to thank Fabio Avino and Joaquim Loizu for their helpful discussions and the CRPP technical team for their essential support.  ... 
doi:10.1088/0741-3335/55/12/124021 fatcat:4vz52vl7afaoxnhcrqkspskhui
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