Die Methode der Normallösungen für die Vlasov-BGK-Gleichung

The linearized Vlasov equation with collision damping is solved by the method of normal modes of Van Kampen and Case. The system considered is an infinitely extended nonrelativistic nondegenerate electron gas with neutralizing ion background and neutral particles. There is no magnetic field. Collision damping is taken into account by complete Bhatnagar-Gross-Krook collision integrals for electron-electron collisions and electronion collisions; in the case of a partially ionized gas elastic collisions between electrons and neutrals can be included likewise. The Vlasov-BGK operator is transformed into an integral operator yielding complex singular normal modes even if the equilibrium distribution is a Maxwellian. The adjoint integral equation belongs to a more complicated type than that of a collision-free system. Its solutions must be orthogonalized. The set of all normal modes is complete rendering the exact solution of the initial value problem possible. The completeness is shown by transformations and regularization of the singular integral equation of the initial value problem, the techniques of Case not being applicable because of the complicated type of this equation.     

Die Geschwindigkeitsverteilung der Ionen in der Freifallsäule

The velocity distribution of the ions in the positive column of the free-fall type discharge is derived by means of the method of characteristics from collisionless Boltzmann equation extended by a source term in plane and cylindrical geometries. A homogeneous axial magnetic field and the initial distribution of ion velocities is taken into account. The formula of Tonks and Langmuir for ion density is reproduced in case of vanishing initial velocity of the ions and vanishing magnetic field.     

Die Anwendung der Methode der zeitlich korrelierten assoziierten Teilchen (MEZKAT)

The TCAPM was developed to absolute and precise fission cross section measurement for neutron energies from 2 MeV up to 19 MeV. Experimental results of absolute fission cross section measurements on ²³³U, ²³⁵U, ²³⁸U, -²³⁷Np, ²³⁹Pu and ²¹²Pu are given. Furthermore the TCAPM is suitable for the application of inelastic scattering of neutrons by the analysis of element contents.     

Die Erhaltung der Teilchenzahlen in der allgemeinen Relativitätstheorie

The Conservation of Particle-Numbers in General Relativity If in a special relativistic field theory the particle number is an integral of a conservation law for a particle-current, then the conservation of the particle-number is valid in general relativity, too.     

Die Aktivierungsfläche bei der Versetzungsbewegung

The activation area for the motion of dislocations is deduced by means of thermodynamic theory of the transition state. Assuming an exponential dependence of the slip velocity as a function of the applied stress and using additional simple statements the activation area is obtained in terms of parameters, which can be determined experimentally. Further on it is shown that one has to distinguish between different definitions of the activation area.     

Eine Methode zur Bestimmung der Viskosität eines Plasmas bei Atmosphärendruck

In this paper a simple method is described to measure the viscosity of a plasma at atmospheric pressure: If spheres move through a cylindrical plasma perpendicular to the axis they undergo a deflection from which the resistance coefficient can be calculated. Measuring too the dynamic pressure and the temperature and knowing the resistance coefficient as function of the Reynolds number the viscosity can be computed. As an example the measurement of the viscosity of a nitrogen plasma is reported.