Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Alfvén and fast wave forces, affecting ions in magnetic traps with closed magnetic surfaces (1999)
    [S.l.] : American Institute of Physics (AIP)
    Physics of Plasmas 6 (1999), S. 1378-1381 
    Details
    ISSN: 1089-7674
    Source: AIP Digital Archive
    Topics: Physics
    Notes: General expressions for time- and surface-averaged radio frequency forces, affecting ions in closed toroidal devices, are obtained in this paper. Toroidal effects are included in these forces. These effects can, for example, be important to calculate Alfvén or fast wave forces in stellarators, spheromaks, or for toroidicity induced Alfvén wave eigenmodes (TAE) in axially symmetric tokamaks. The further simplification of obtained expressions should be fulfilled for the proper kind of rf waves and toroidal devices. It is hoped that these rf force expressions can, for example, be useful for the computer simulations of the transport barrier formation by Alfvén and fast waves in toroidal devices. © 1999 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.873377
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Calculations of Alfvén wave driving forces, plasma flow, and current drive in the Tokamak Chauffage Alfvén wave experiment in Brazil (TCABR) (2001)
    [S.l.] : American Institute of Physics (AIP)
    Physics of Plasmas 8 (2001), S. 210-215 
    Details
    ISSN: 1089-7674
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The current and plasma flows driven by ponderomotive forces are calculated for tokamak plasmas, using a kinetic code in the Alfvén range of frequencies. The rf (radio frequency) ponderomotive force is expressed as a sum of a gradient part and of a wave momentum transfer force, which is proportional to wave dissipation (electron Landau damping and transit time magnetic pumping). Finally, the rf force is balanced by the viscous force in the fluid momentum response to the rf fields in the plasma. The relative magnitudes of the different forces for kinetic and global Alfvén waves with low phase velocities are explicitly calculated. It is shown that, dissipating in electrons, Alfvén waves can drive ion flow via the gradient force, which is dominated in m=0-sideband harmonic resonance induced by toroidal mode coupling. Estimates of power requirements to drive substantial poloidal flow in the Tokamak Chauffage Alfvén wave heating experiment in Brazil (TCABR) [L. Ruchko, M. C. Andrade, R. M. O. Galva˜o, Nucl. Fusion 30, 503 (1996)] are made. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1332813
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Comment on "Alfvén wave current drive in tokamak rotating plasma with negative magnetic shear" [Phys. Plasmas 6, 4633 (1999)] (2000)
    [S.l.] : American Institute of Physics (AIP)
    Physics of Plasmas 7 (2000), S. 3119-3119 
    Details
    ISSN: 1089-7674
    Source: AIP Digital Archive
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.874170
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Alfvén wave heating and current drive : The 42nd annual meeting of the division of plasma physics of the American Physical Society and the 10th international congress on plasma physics (2001)
    [S.l.] : American Institute of Physics (AIP)
    Physics of Plasmas 8 (2001), S. 2050-2056 
    Details
    ISSN: 1089-7674
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Progress in the theory of Alfvén wave (AW) heating, current drive, and plasma flow, which may be relevant for improved confinement scenarios in tokamaks, is discussed. The effect of poloidal mode coupling on the power deposition of AW eigenmodes is investigated. Resonant absorption of the coupled side bands causes a broad power deposition close to the plasma boundary which can surpass the power deposition of the main global AW at the plasma center. A small population of impurities, such as carbon, in a hydrogen plasma can strongly modify the dispersion of the global AW, the AW continuum and the wave dissipation profile. The ponderomotive forces produced by rf fields are expressed as a sum of a gradient (radial derivative) part and of a wave momentum transfer force found to be proportional to wave dissipation. Finally, the rf force is balanced by the friction (or neo-classical viscosity) force to calculate relevant current drive and plasma specie flows. Estimates of AW power requirements to drive substantial heating, current, and poloidal flow are made for plasmas in the Tokamak Chauffage Alfvén wave experiment in Brazil (TCABR) [L. Ruchko et al., Nucl. Fusion 30, 503 (1996)]. The first results of Alfvén wave heating and current drive experiments with a low level of wave dissipation in the TCABR are discussed. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1350572
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    The Coulomb scattering effect on trapped particles bounce-resonance dissipation in magnetized toroidal plasmas (1999)
    [S.l.] : American Institute of Physics (AIP)
    Physics of Plasmas 6 (1999), S. 1547-1553 
    Details
    ISSN: 1089-7674
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The solution of the Vlasov equation with a simplified Fokker–Planck collision operator is presented for axially symmetric tokamak plasmas with a circular cross section of magnetic surfaces. The analytical expression for the parallel component of the dielectric permittivity tensor of trapped particles is obtained. This expression is used for theoretical analyses of the collision effect on the bounce-resonance wave dissipation. Conditions for a collisionless description of radio-frequency (rf) oscillations are found. This dielectric tensor components can be used for computer calculations of the rf field structure and the rf dissipated power related to trapped electrons in tokamak plasmas. © 1999 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.873408
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Anomalous electron precipitation near the Earth's auroral zone induced by the wave–particle interaction (1997)
    [S.l.] : American Institute of Physics (AIP)
    Physics of Plasmas 4 (1997), S. 2269-2275 
    Details
    ISSN: 1089-7674
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The results of a numerical simulation of anomalous electron precipitation in the Earth's auroral zone induced by waves are discussed. In order to study the plasma electron–wave interaction, a two-dimensional quasilinear code has been used. A quasilinear operator models the electron Landau damping of any plasma eigenmodes: kinetic Alfvén waves, whistlers, lower hybrid waves, etc. The distribution function structure was analyzed. The electron current induced by waves, the density, and the plasma energy decay, which stimulates the electron precipitation, have also been investigated. © 1997 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.872390
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Alfvén waves and rotation of collisional plasmas in tokamaks (1996)
    [S.l.] : American Institute of Physics (AIP)
    Physics of Plasmas 3 (1996), S. 2818-2820 
    Details
    ISSN: 1089-7674
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The effect of radio frequency fields on a plasma rotation in the edge (collisional) region of slightly rippled tokamaks is considered. The expressions for poloidal and toroidal velocities and for quasistationary radial electric fields are obtained as a function of absorbed rf power. The estimations of these quantities for the Phaedrus-T tokamak [N. Hershkovitz et al., 15th International Atomic Energy Agency Conference on Plasma Physics and Controlled Fusion, Seville, 1994 (International Atomic Energy Agency, Vienna, in press)] are also presented. It is shown that Alfvén waves can strongly modify the rotation velocities and radial electric fields in collisional regions of tokamak plasmas. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.871716
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Hydrodynamic description of Alfvén and fast wave current drive in weakly collisional plasmas of magnetic traps (1995)
    [S.l.] : American Institute of Physics (AIP)
    Physics of Plasmas 2 (1995), S. 2784-2789 
    Details
    ISSN: 1089-7674
    Source: AIP Digital Archive
    Topics: Physics
    Notes: In this paper, general aspects of the Alfvén and fast wave nonresonant and resonant current-drive problem are considered both for collisional and weakly collisional plasmas. The magnetohydrodynamic approach is used for all collisional regimes and Landau damping is taken into account in the weakly collisional plasma case. Averaged in time and over magnetic surface, the general form of current-drive forces are derived, including the viscosity and collision frequency perturbation terms. As an example, a weakly collisional plasma cylinder case is discussed and some disagreements on this problem between different authors results are eliminated. © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.871176
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Rotation of weakly collisional plasmas in tokamaks, operated with Alfvén waves (1996)
    [S.l.] : American Institute of Physics (AIP)
    Physics of Plasmas 3 (1996), S. 4606-4609 
    Details
    ISSN: 1089-7674
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The effect of the kinetic Alfvén waves on weakly collisional plasma rotation in tokamaks has been studied for the plateau and banana regimes. The quasistationary rotation velocities and radial electric field have been found. The estimation of these quantities for the Phaedrus-T tokamak [S. Wukitch et al., Phys. Rev. Lett. 77, 294 (1996)] and for the Joint European Torus (JET) [A. Fasoli et al., Nucl. Fusion, 36, 258 (1996)] has been presented. It is shown that the kinetic Alfvén waves, which are needed for current drive, change weakly the quasistationary rotation velocities and radial electric field, as found from the experimental data of these tokamaks. In conditions with increased rf power, the plasma rotation and radial electric field can essentially grow up. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.872031
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Influence of trapped electrons on the dielectric properties of the Earth's radiation belts (1996)
    [S.l.] : American Institute of Physics (AIP)
    Physics of Plasmas 3 (1996), S. 3798-3808 
    Details
    ISSN: 1089-7674
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The dielectric tensor of an axisymmetric magnetosphere is derived by solving the Vlasov equations for trapped particles for a two-dimensional plasma model with circular magnetic field lines. Because of the nonuniformity of the geomagnetic field any Fourier harmonic of the perturbed current density (after its Fourier expansion over the geomagnetic latitude) is proportional to the sum over all harmonics of the oscillating electric field; that leads to additional wave dissipation effects. The resonant conditions for wave–particle interactions are discussed taking into account the cyclotron and bounce resonances; these conditions in magnetospheric plasmas are entirely different from the Landau damping resonant factor in the uniform magnetic field. The numerical calculations of the longitudinal permeability in the Earth's radiation belts (the equatorial distance of the magnetic field line is five Earth's radii) are carried out for short-period oscillations with the frequency ω∼2 s−1 and longitudinal wave numbers n=1,...,15. The different energy levels of the trapped electrons, T∼40–4000 eV, are considered. It is shown that, in the low-frequency region, the imaginary part of the longitudinal permeability decreases as ∼T−2.5 whereas the electron temperature increases. This decrease is stronger than ∼T−1.5 for plasmas in a straight magnetic field. For a given wave frequency, the basic contribution of trapped electrons to the imaginary part of longitudinal permeability is associated with the low numbers of bounce resonances and the low longitudinal wave numbers. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.871512
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...