arXiv subjects

Manfred Fink

Publications and source records attributed to Manfred Fink.

2 recordsLinked to original sources

arXiv1999

Investigation of a 90 Degree Spherical Deflecting Analyzer Operated in an Asymmetrically Charged Configuration

The electron optics of a 90 degree spherical deflecting analyzer (SDA-90) is investigated with an imaging matrix formalism. As a preanalyzer in the UTA-neutrino experiment, high transmission and reasonable energy resolution are the choices of optimization. The magnification of the source through the analyzer plays the key role in determining the energy resolution. The imaging matrix approach provides graphical information to facilitate such an evaluation. We can demonstrate that in case where the analyzer is asymmetrically charged, the rotation of the image helps increase both transmission probability and resolution. A telefocus electron gun is used to check the numerical result, and to investigate the transverse focusing behavior.

physics.optics↗

arXiv1999

Emission Optics of the Steigerwald Type Electron Gun

The emission optics of a Steigerwald type electron gun is re-examined. The virtual and real points of divergence, divergence angles and beam-widths of the electron beams at different telefocusing strength are measured in detail for first time . Two different Wehnelt cylinders are used to establish a contrasting viewpoint. The original `focusing' curves measured by Braucks are reconstructed and will be explained only through a `new' interpretation which is different from the conventional views. While the image of the emitting surface in front of the filament is indeed telefocused beyond the anode, the envelope of the beam does not `focus' as expected. A new model for the emission mechanism is established based on our results.

physics.optics↗