The grain density and the process of track formation in nuclear emulsions

The method described in paper I for the evaluation of π (the probability that a grain be impressioned) has been applied to ~ 50 tracks, observed in Ilford G5 Plates and belonging to identifiable particles of a given range. Experimental data have been plotted versus energy loss and compared with the expression given by P. Demers. It is recognized that some modification of the theory is required to account for the results. In fact, it is shown that the discrepancies can be made to disappear if the effect of the electron recombination inside the grain is suitably taken into account.