Partial inelasticity coefficients of negative pions in p, d, α, <sup>12</sup><font>C</font>+<sup>12</sup><font>C</font> and p, <sup>12</sup><font>C</font>+<sup>181</sup><font>Ta</font> collisions at 4.2 GeV/c per nucleon
Аннотация
The partial inelasticity coefficients of the negative pions were determined in minimum bias p, d, α, 12 C + 12 C and p, 12 C + 18 Ta collisions at 4.2A GeV/c taking into account the average number of participant nucleons of a projectile nucleus. In nucleus–nucleus collisions, the average values of partial inelasticity coefficients (〈K(π - )〉) of the negative pions did not depend on the mass numbers of projectile and target nuclei. Increase of 〈K(π - )〉 in going from p+ 12 C to d, α, 12 C + 12 C collisions was due to an additional source of production of fast negative pions in nucleus–nucleus collisions — a charge exchange conversion of one or more neutrons of a projectile nucleus into a proton and π - . Linking the experimental results of the present analysis at intermediate energy with those obtained at high and ultra-high energies, it was concluded that the average values of partial inelasticity coefficients of pions in nucleon–nucleus and nucleus–nucleus collisions manifest a transitive behavior. At intermediate energies, the values of 〈K(π - )〉 were smaller by a factor of two and more as compared to those at high energies, and they increased further with increasing incident energy, reaching a plateau at E 0 > 100A GeV.