Scattering of Monoenergetic Argon Beams from Heated Platinum: Planar Time-of-Flight Measurements

Time-of-flight measurements were made in the plane of incidence with initially monoenergetic argon beams (speeds 5.4 × 104 and 9.55 × 104 cm/sec) before and after reflection from heated platinum. The time-of-flight data were used to compute low-order moments of velocity distribution: relative number flux, momentum, and energy flux. Flux ratios yield mean speed, mean energy, and speed distribution as functions of angle of reflection. In all cases the mean speed and mean energy of the reflected stream show marked angular dependence, decreasing at a given incidence angle with increasing angle of reflection from the target normal. The mean tangential velocity of the reflected stream is close to that of the incident beam. Calculated incident beam speed distributions are near 0.1 whereas in the reflected streams values are closer to the Maxwellian limit 0.363.