VELOCITY ANALYSIS OF LAVAL BEAMS (GESCHWINDIGKEITSANALYSE VON LAVAL-STRAHLEN),
Abstract
Velocity distributions of molecular beams of hydrogen, argon, and a mixture of both gases were studied with a transit-time apparatus. It is shown that the use of a Laval nozzle can reduce the relative half-value widths of distributions in pure gases by a factor of 2, relative to normal 'oven' beams. Most probable velocities of 2700, 1450, and 960 m/sec are obtained for hydrogen molecular beams generated with the nozzle: at room temperature, with liquid air as a coolant, and with liquid hydrogen as a coolant. A practically pure argon beam, with a most probable velocity of 1240 m/sec and a half-value width of 260 m/sec, can be obtained at room temperature by accelerating a mixture of 20% argon and 80% hydrogen and then removing the light component. The low relative half-value width of velocity distribution and the large absolute velocity allow the flux density of argon to be raised by one or two orders of magnitude versus that of a normally generated molecular beam. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1964
- Accession Number
- AD0837044
Entities
People
- E. W. Becker
- W. Henkes
Organizations
- American Meteorological Society