Pion production from heavy-ion collisions is calculated in the independent-particle model, using nucleon-nucleon cross section data as input information. The assumption is made that only the first collision of a nucleon pair can create a pion, and also all collective effects are neglected. For the representative case of ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ bombardment of ${}_{}{}^{238}{}_{}{}^{}\mathrm{U}$ at 250 MeV/nucleon, one out of seven inelastic collisions should produce a pion. One-third of these pions should be able to escape to the outside. The pion spectrum peaks at 20 MeV with an average energy of 50 MeV, viewed in the nucleon-nucleon center-of-mass frame.

NUCLEAR REACTIONS Pion production in heavy-ion collisions, calculate $\sigma$, $\sigma \left(E_{\pi }\right)$.

• Received 20 September 1976

DOI:https://doi.org/10.1103/PhysRevC.15.713