The Rest Mass of the Mesotron

The experimentally found values for the lifetime at rest of the cosmic-ray mesotron, from recent reliable investigations by various authors, are directly compared after recalculating them on the basis of the same assumed rest mass. The thus corrected values for the lifetime still disagree, but are shown to be a function of the average path length of the radiation employed in each experiment. When, instead of the existence of only one possible value for the rest mass for which we have no experimental evidence, a distribution in rest masses is assumed, the described phenomenon can be accounted for regardless of what form the mass distribution may have. The same assumption leads to explanations of other experimental findings, and predicts an actual lifetime ${\tau }_0$ much smaller than any measured value, strongly indicating that upon correcting the measured results on the basis of the existence of a mass distribution, a value of the order of Yukawa's original prediction ${\tau }_0=5\mathrm{}\times {10}^{ 7}$ sec. is obtained.