Negative pion transfer process in a hydrogen-containing gas mixture

Annihilation gamma-rays of pi(0) and pionic X-rays were measured in the gas mixtures of H-2+Z and CH4+Z systems (Z=He, Ne, Ar and Kr). Pion capture pr obability of hydrogen atom was obtained from the annihilation gamma-ray cou nts and the capture probability of Z atom was obtained from the pionic X-ra y intensities. Transfer rates were determined from the data based on a comb ined large mesomolecular model. The transfer rates obtained were smaller th an the systematics of the Russian group. Difference in the transfer rate be tween the gas and the liquid phases was found by a comparison of the presen t results with our previous ones.