  A predominantly electric E\&m storage ring, with weak superimposed magnetic
bending, is shown to be capable of storing two different particle type bunches,
such as helion (h) and deuteron (d), or h and electron ($e^-$), co-traveling
with different velocities on the same central orbit. Rear-end collisions
occurring periodically in a full acceptance particle detector/polarimeter,
allow the (previously inaccessible) direct measurement of the spin dependence
of nuclear transmutation for center of mass (CM) kinetic energies (KE) ranging
from hundreds of keV up toward pion production thresholds. With the nuclear
process occurring in a semi-relativistic moving frame, all initial and final
state particles have convenient laboratory frame KEs in the tens to hundreds of
MeV. The rear-end collisions occur as faster stored bunches pass through slower
bunches. An inexpensive facility capable of meeting these requirements is
described, with several nuclear channels as examples. Especially noteworthy are
the $e^{+/-}$-induced weak interaction triton (t) $\beta$-decay processes, t +
$e^+ \rightarrow$ h + $\nu$ and h + $e^- \rightarrow$ t + $\nu$. Experimental
capability of measurement of the spin dependence of the induced triton case is
emphasized. For cosmological nuclear physics, the experimental improvement will
be produced by the storage ring's capability to investigate the spin dependence
of nuclear transmutation processes at reduced kinetic energies compared to what
can be obtained with fixed target geometry.
