Pontecorvo reactions of two-body annihilations anti pd and anti p3He and multiquark states in d and 3He

We discuss the probabilities of the Pontecorvo reactions anti p 3He → pn and anti pd → π-p at rest and relate them to the admixtures of multiquark states in d and 3He. The treatment is based on the relativistic two-step model and gives asymptotics of the amplitudes similar to the predictions of reduced QCD amplitude approach. According to our estimation, the ratio R = σ(anti p 3He → pn)/σ(anti pd → π-p) is < or approx. 10-3 for stopped antiprotons. (orig.)