A SIMPLE MECHANISM OF THE PONTECORVO REACTION

The following mechanism of two-particle p-d annihilation is considered . At the first stage, an antiproton annihilates with one of the nucleo ns of the deuteron and produces two mesons. These mesons, in tum, inte ract with the remaining nucleon and produce a nucleon and a pi-meson. The imaginary part of the amplitude of such a process is expressed in terms of the amplitudes of elementary processes in the physical region . The calculation of the contribution from this mechanism is carried o ut under simplifying assumptions and gives, therefore, only an approxi mate estimate. Nevertheless, the numerical results show that the contr ibution of several channels to the branching ratio of the Pontecorvo r eaction is on the order of 10(-5); this value is in agreement with the experimental data.