Theory of a Probe in a Strong Magnetic Field. AT(30-1)-1238-MATT 599

A kinetic approach is used to develop a theory of electrostatic probes in a fully ionized plasma in the presence of a magnetic field. A consistent asymptotic expansion is obtained assuming that the electron Larmor radius is small compared to the radius of the probe. The order of magnitude of neglected terms is given. It is found that the electric potential within the tube of force defined by the cross section of the probe decays non-mono tonic ally from the probe; this bump disappears at a certain probe voltage and the theory is valid up to this voltage. The transition region, which extends beyond plasma potential, is not exponential. The possible saturation of the electron current is discussed. Restricted numerical results are given; they seem to be useful for weaker magnetic fields down to the zero-field limit. Extensions of the theory a r e considered.

Discurso pronunciado por el Excmo. Sr. D. Rafael Portaencasa Baeza, Rector Magnífico de la Universidad Politécnica de Madrid, en el acto de apertura del curso académico universitario 1991-92

Discurso pronunciado por D. Rafael Portaencasa Baeza, Rector de la Universidad Politécnica de Madrid, en el acto de apertura del curso académico universitario 1991-92. En sus palabras el Rector hace un balance de sus primeros ocho meses y medio como máximo responsable de la UPM y analiza la situación de los distintos centros de esta institución.