ISSN:
1089-7623
Source:
AIP Digital Archive
Topics:
Physics
,
Electrical Engineering, Measurement and Control Technology
Notes:
The characteristics of a molecular beam from a piezoelectric pulsed nozzle source are given and, where appropriate, compared to a continuous beam. These include variation during the pulse in the relative intensity and speed ratio for the gases He, Ar, Ne, and N2. The measurements were made by standard time-of-flight and laser-induced fluorescence techniques. For gas valve pulses of time duration less than 500 μs, there was a single peak during which the gases reached continuum steady flow behavior. Typical speed ratios (parallel temperatures) for the gases He, Ar, Ne, and N2 were 19, 34, 34, and 20 (2.1, 0.7, 0.7, and 1.9 K), respectively. These values are comparable to those from a continuous source with equivalent values of p0d, the product of source pressure and nozzle diameter. The dimer concentrations for Ne and Ar were also measured and found to be 0.4% and 0.7%, respectively. A major problem with the valve was its inability to open fully because of the limited motion of the piezoelectric element.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.1138414
