Geometrical effects in antiproton annihilation on nuclei - art. no. 027301

The importance of geometrical effects in the A dependence of many observabl es regarding antiproton annihilation on nuclei is expected on theoretical g rounds. The cases of the charged pion multiplicity and of the frequency of the so-called single nucleon events are examined. In the first case. the re spective roles of surface diffuseness, partial nuclear opacity, and pion ab sorption mechanism are examined. The possibility of extracting from compari son with experiment the average location of the annihilation site is critic ally discussed. The obtained values are in agreement with current theoretic al estimates.