Dortmund 2006 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

T: Teilchenphysik

T 205: Neutrinos I

T 205.9: Vortrag

Dienstag, 28. März 2006, 16:00–16:15, HG2-HS6

The condensed ^83mKr Calibration Source for KATRIN — •Matthias Prall — Institut für Kernphysik, Westfälische Wilhelms-Unversität, Wilhelm-Klemm Str. 9, D-48149 Münster

The KATRIN experiment relies on the stability of the retarding voltage of 3 ppm at 18.6 kV. KATRIN will apply this retarding voltage to a third retarding spectrometer, the ‘monitor’ spectrometer, with which a sharp and well-defined electron line will be measured frequently or continuosly. Several sources based on atomic and nuclear standards are under development. Our approach is the K-32 conversion line of ^83mKr at 17.8 keV with a width of 2.9 eV. The half-life of ^83mKr is 1.83h, therefore the reproducibility is the challenge. The ^83mKr is frozen with possible noble gas underlayers as submonolayer onto a graphite substrate. We present a UHV set up with which we are able to produce thin films with high purity, measure their thickness with ellipsometry and transport ^83mKr atoms towards the substrate. The set up cleans noble gases with cold and getter traps. The substrate is cleaned with pulses from a Q-switched laser. Our condensed ^83mKr conversion electron source is currently being tested at the Mainz MAC-E Filter.

This work is supported by German Bundesministerium für Bildung und Forschung under contract 05CK5MA/0 and by the virtual institute VIDMAN of the Helmholtz Gemeinschaft.