Analysis of the Two-Mode-of-Fission Hypothesis

Mass yields for gamma fission of ${\mathrm{U}}^{238}$, proton fission of ${\mathrm{Th}}^{232}$, alpha fission of ${\mathrm{U}}^{238}$, and deuteron fission of normal uranium have been examined in terms of vector spaces for consistency with the hypothesis that for each target and projectile there are two and only two modes of fission. The first three cases are on the whole consistent with the hypothesis. The fourth is not consistent with the hypothesis; the measured yields include some yields from neutron fission. Some consequences of the hypothesis with the added requirement of non-negative yields and non-negative coordinates are derived.