Accession Number : AD0837044

Title :   VELOCITY ANALYSIS OF LAVAL BEAMS (GESCHWINDIGKEITSANALYSE VON LAVAL-STRAHLEN),

Corporate Author : AMERICAN METEOROLOGICAL SOCIETY BOSTON MA

Personal Author(s) : Becker, E. W. ; Henkes, W.

Report Date : JUL 1964

Pagination or Media Count : 19

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)

Descriptors :   *MOLECULAR BEAMS), (*LAVAL NOZZLES, HYDROGEN, ARGON, GASES, COOLANTS, VELOCITY, SCATTERING, DENSITY, IONIZATION, NOZZLE GAS FLOW, DISTRIBUTION FUNCTIONS, PARTICLES, DETECTORS, PRESSURE, MIXTURES.

Subject Categories : Test Facilities, Equipment and Methods
      Nuclear Physics & Elementary Particle Physics
      Rocket Engines

Distribution Statement : APPROVED FOR PUBLIC RELEASE