摘要:

AbstractMagneto‐acoustic waves generated by fluctuations in the Hall parameter, the electric conductivity and the stream velocity are theoretically investigated in a weakly ionized plasma streaming across a strong external magnetic field and bearing a current flowing perpendicular to both magnetic field and stream velocity. The investigations hold for seeded rare gas plasmas at any degree of seed ionization but are resticted to waves propagating in parallel or antiparallel direction to the current density vector and in parallel or antiparallel direction to the stream velocity vector and to wave lengths which are small in comparsion to the interaction length which occurs as a characteristic wave length. The influence of these waves on the mean current density and the mean Hall field intensity is calculated in case of small amplitudes and low degree of seed ionization up to second order terms.Omitting Ohmic heating the dispersion equation can be solved exactly. A phase shift exists between the fluctuations in gas density and gas velocity. The phase velocity and the amplification rate depend on the wave length. Typical results are represented in a diagram. For both types of waves the phase velocity slightly rises with increasing wave length, while the amplification rate decreases.Waves propagating in opposite direction to the current density vector are amplified, if the electron velocity exceeds a critical value. They reduce the mean current density and the mean Hall field intensity. Waves propagating in opposite direction to the stream velocity vector are also amplified except for very high degrees of seed ionization. The threshold current density is greater than that for the waves of the first type approximately by the Hall parameter as factor. At extremely high degree of seed ionization the phase velocity is directed opposite to the direction occuring at weakly ionized seed.Waves of the second type decrease the mean current density, but increase the mean Hall field intensit

ISSN:0005-8025    

DOI:10.1002/ctpp.19700100302

出版商:WILEY‐VCH Verlag    

年代:1970

数据来源: WILEY

摘要:

AbstractThe phase velocity, the amplification rate and the critical Hall parameter are theoretically determined for ionization waves in a weakly ionized plasma streaming across a strong external magnetic field and bearing a current flowing perpendicular to both the magnetic field and the stream velocity. The investigations hold for seeded rare gases at any degree of seed ionization. The critical Hall parameter βcdepends on the degree of ionization, the ionization energy and the temperatures of electron gasT0and neutral gasTg· βcis always greater than one, if 0

ISSN:0005-8025    

DOI:10.1002/ctpp.19700100303

出版商:WILEY‐VCH Verlag    

年代:1970

数据来源: WILEY

摘要:

AbstractUsing the resolvent representation of the binary Boltzmann operator the second virial coefficient is expressed by a contour integral over the Jost function of the two‐particle scattering problem. This new formula is useful for many general investigations and also for practical calculations if the Jost functions for the scattering problem are known. As special examples real gases with hard core potentials and fully ionized plasmas with Coulomb interactions are treated. For the plasma case the second virial coefficient is derived without approximations with respect to the interaction parameter. The contribution of the bound states to the free energy is discussed and compared with the effect of ionic association to the classical free energy and the conductivit

ISSN:0005-8025    

DOI:10.1002/ctpp.19700100304

出版商:WILEY‐VCH Verlag    

年代:1970

数据来源: WILEY

摘要:

AbstractEs werden die inneren Entladungsparameter (ne,Te,E/p0) der positiven Säule einer Neonentladung bei mittleren Gasdrücken unter Berücksichtigung sowohl einer Abweichung der Energieverteilungsfunktion der Elektronen von einer Maxwell‐Verteilung als auch radiale Inhomogenitäten der Gasdichte und Elektronentemperatur errechnet. Die berechneten Parameter werden mit experimentellen Daten vergl

ISSN:0005-8025    

DOI:10.1002/ctpp.19700100305

出版商:WILEY‐VCH Verlag    

年代:1970

数据来源: WILEY

摘要:

AbstractZur Berechnung der Stromdichte in einem zylindrischen von Diffusion und Attachment bestimmten Elektronenstrahlplasma wird das Magnetfeld als Vektorpotential eingeführt. Für die entstehende elliptische Differentialgleichung werden die Randbedingungen aufgestellt, die im quasineutralen Fall wegen der an den Rändern verschwindenden Dichte gewissen Einschränkungen unterliegen. Das Randwertproblem ist nur numerisch lösbar. Als Beispiel werden Stromdichten und Feldstärken im Glimmlicht von kontrahierten anomalen Wasserstoff‐Glimmentladungen berechnet. Es ergibt sich, daß die Ambipolarität der Radialströme auch bei stärker kontrahierten Entladungen in guter Näherung erfüllt ist. Einige Möglichkeiten für Vergleiche mit Experimenten werden diskutiert.The current density in a cylindrical beam‐generated plasma with diffusion and attachment losses is calculated by introducing the magnetic field as vector potential. The boundary‐values for the elliptic partial differential equation resulting from this procedure are submitted to certain restrictions for the case of a quasineutral plasma. The boundary‐value‐problem is solved numerically.As an example, current densities and electrical fields of the negative glow of constricted anomalous H2‐discharges are computed. The results show that even for higher degrees of constriction the radial currents are ambipolar. Some aspects of comparison to

ISSN:0005-8025    

DOI:10.1002/ctpp.19700100306

出版商:WILEY‐VCH Verlag    

年代:1970

数据来源: WILEY

摘要:

AbstractIt is shown, that the wall current of the striated positive column in a neon low pressure glow discharge is modulated with the frequency of the moving striations. There is a phase shift between wall currents of electrons and ions (∼π/2–3/4π), A mass‐spectrometric analysis of the ion currents shows Ne+and Ne2+ions, both currents are modulated. The modulation factor of the electron and ion current reaches values near 100% and 50%, repectively. The behaviour of the modulated wall currents may by explained by the potential oscillations in the Langmuir sheath near t

ISSN:0005-8025    

DOI:10.1002/ctpp.19700100307

出版商:WILEY‐VCH Verlag    

年代:1970

数据来源: WILEY

ISSN:0005-8025    

DOI:10.1002/ctpp.19700100301

出版商:WILEY‐VCH Verlag    

年代:1970

数据来源: WILEY