(e, 3e) test on e-e correlations in helium

The angular variations of the five-fold differential cross section obtained by using different wave functions of helium are compared with experimental data. It is found that in the coplanar geometry two kinematical arrangements, (i) equal energy sharing between the two ejected electrons with one of them ejected along the momentum transfer direction and the other along varying direction and (ii) the Bethe ridge condition with fixed sum of ejected electron energies and varying angle between them, are very sensitive to e-e correlations contained in the target wave function. This comparison has been used to show that open-shell class of wave functions better incorporate e-e correlations than the closed-shell class.     

The thermistor problem

In this paper we prove the existence of a classical solution of the thermistor problem. Received May 15, 1995     

Theory of sheath in a collisional multi-component plasma

The aim of this brief report is to study the behaviour of sheath structure in a multi-component plasma with dust-neutral collisions. The plasma consists of electrons, ions, micron size negatively charged dust particles and neutrals. The sheath-edge potential and sheath width are calculated for collisionally dominated sheath. Comparison of collisionless and collisionally dominated sheath are made.     

Nachweis und Bestimmung von Nitraten in der Milch

Ohne Zusammenfassung     

(e, 3e) Differential cross section of He (21 S) and He (23 S)

The angular distribution of the five-fold differential cross section for the electron impact double ionization of He (2¹ S) and He (2³ S) has been studied. The kinematical conditions for maxima/minima in the angular distribution for the two cases have been compared. The two-step process for the double ionization is found to contribute very little in the triplet case.     

Static aes-the adequate mode of aes for surface reaction and submonolayer adsorption studies

Evidence is presented of a need for static AES, i.e. direct counting of the N(E) distribution at low primary electron current densities and under UHV conditions, in the investigation of metal-adsorbate interactions in the monolayer and submonolayer range. After appropriate modifications of the standard equipment, sufficient sensitivity can be reached by this method without undesired peak distortion by potential modulation and beam-induced surface changes.