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Updated: Jul 16, 2026

An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Kinematic slowing of molecules formed by reactive collisions
Ning-Ning Liu1, Hansjürgen Loesch
1Fakultät für Physik, Universität Bielefeld, Universitätsstrasse 25, D-33615 Bielefeld, Germany.
Abstract:
We report the generation of a beam of slow (translationally cold) KBr molecules formed by exoergic reactive collisions in counterpropagating beams of K atoms and HBr molecules. The intensity of the slow beam is estimated to 4x10(11) s-1 sr-1. The velocity distribution (density) peaks at 42.5 m/s corresponding to a formal temperature of 13 K. About 7% of the molecules move at velocities between 14.2 and 20 m/s and an estimated fraction of 7% is slower than 14.2 m/s.
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