Point Density Measurement, of a Gas by Coincidence-counting Method

Abstract

The conventional methods used to determine the air stream density, distribution density in shock waves shock wave thickness, pressure altitude, etc, are based on the probe-type instruments in the nuclear technology make It possible to measure properties of a gas without disturbing the media being observed. Coincidence-counting techniques simplify the point density measurement by eliminating the need to know absolutely the detect or efficiencies, geometry factors, etc. The background due to cosmic rays, multiple-scattering of photons or particles, wall scattering, etc. is reduced by this method. Therefore the source required for this method is discussed in this work. Calculated results for source size for various altitudes are presented here. This study shows that the Coincidence-counting methods for gas density measurement is good and an experimental trial is feasible.