Limits on the low energy antinucleon-nucleus annihilations from the   Heisenberg principle
  We show that the quantum uncertainty principle puts some limits on the effectiveness of the antinucleon-nucleus annihilation at very low energies. This is caused by the fact that the realization a very effective short-distance reaction process implies information on the relative distance of the reacting particles. Some quantitative predictions are possible on this ground, including the approximate A-independence of antinucleon-nucleus annihilation rates. 
A.Bianconi, G.Bonomi, M.P.Bussa, E.Lodi Rizzini, L.Venturelli,   A.Zenoni