Speed ratios of neon nozzle beams

At the present time there appears to be no limit in the speed ratios of nozzle beam expansions in helium. Large speed ratios are not expected in heavier gases since quantum effects are smaller. Furthermore with increasing dimer dissociation energy condensation effects are anticipated to lead to a heating of the gas. The purpose of the present work was to carry out a careful study of nozzle beams in neon which by virtue of its small dissociation energy (25.30K) and light mass should show a behaviour intermediate between He and the heavier rare gases. In the present study the stagnation temperature was varied from 770K to 6000K. (Auth.)