Berlin 2005 – wissenschaftliches Programm
SYCM 2.3: Hauptvortrag
Samstag, 5. März 2005, 15:30–16:00, HU Audimax
Cold molecules for studying cold chemical reactions — •Hansjürgen Loesch, Ning-Ning Liu, and Dirk Weber — Fakultät für Physik, Universität Bielefeld, Universitätsstraße 25, D-33615 Bielefeld
Elementary chemical reactions form an important and attractive field of application for cold molecules. Detailed experimental information about these processes at low collision energies deepens the insight into their dynamics and is crucial e.g. for a better understanding of the molecule formation mechanisms in cold interstellar gas clouds. Theoretical studies predict interesting quantum phenomena such as tunnelling and resonances. Candidates for first investigations are the three centre reactions of the type A+BC→ AB+C. There are now very efficient methods available to cool down the reagent atoms (A) and new techniques are being developed to produce cold molecules (BC). In this talk a novel technique for the formation of cold molecules is introduced. It is based on reactive collisions between metal atoms (K) and hydrogen-halide molecules (HBr) in the course of which cold salt molecules (KBr) are formed. So far, a significant flux of slow molecules (<30 m/s) has been observed. In addition, the rotating-nozzle-technique for the generation of cold molecules is briefly discussed and results obtained with our improved set-up are presented. To date, quasi-continuous beams of atoms and molecules with peak velocities near 30 m/s have been created.