Sensitivity of Orthopositronium Annihilation Rates to Density Fluctuations in Ethane Gas

Abstract
Orthopositronium annihilation rates have been measured in ethane gas for densities in the range 1.8 to 286 amagats at 306.4 K. The behavior of the measured annihilation rates at densities up to about 70 amagats can be explained in terms of a simple density fluctuation model. New features are observed at higher densities of ethane at 306.4 K.