Pion single-nucleon absorption and the problem of pion condensation

Nuclear reactions induced by stopped negative pions in133Cs,93Nb and45Sc

“…Recent investigation revealed clearly that the absorption process goes through two succesive stepps: i) absorption of a 7z-by a cluster where several fast nucleons and light fragments are produced some of which escape the nucleus without interaction ii) other fast nucleons or light fragments in a series of succesive collisions excite the nucleus which emits direct and evaporated neutrons and charged particles I- [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17].…”

“…Due to the momentum and energy conservation a re-at rest is absorbed by a quasideuteron [1] or by an alphaparticle [2]. Single nucleon absorption involves the nucleon momentum of 500 MeV/c which exceeds significantly the momentum cut-off inside the nucleus and hence it is strongly suppressed [3,4]. The absorption of negative pions has been studied in the past by emulsion, neutron dosimetry and activation technique reviewed for instance by Koltun [-5] and by Htifner [3].…”