Can we breed protactinium from thorium by hitting it with accelerated He ions?
If one induces an (alpha, p) reaction, then one could produce Pa. However, it would be much easier to produce Pa with neutron capture in Th-232, which becomes Th-233, which decays to Pa-233, which decays to U-233, which is fissile.
See the attached for nuclides of Th, Pa, and U.
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