Radiation isn't homogeneous. It's mainly alpha particles (helium nuclei), beta particles (electrons), neutrons, gamma rays (high energy photons), and neutrinos. Anti-uranium would produce anti-matter versions of this. You'd take far more damage from the anti-matter hitting you than you would from the radiation from a like amount of normal uranium.

Uranium can decay by alpha emission or spontaneous fission. Smack it with a slow neutron, and you get two smaller (and probably unstable) nuclei, gammas, neutrinos, and some more neutrons. Reverse the sign on everything if it's anti-uranium and an anti-neutron.

Fred

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