Inclusive and exclusive production of η mesons by pions

Abstract
Inclusive and exclusive (π,η) reactions are studied in the framework of a momentum space DWIA model. It is assumed that both reactions are dominated by formation of an N(1535) resonance. Medium corrections for the self-energy of the intermediate N* are taken into account. Cross sections are calculated for (π+,η) inclusive reactions on C12 and compared with experiment and with existing theoretical calculations. We show that quantitative agreement is obtained with experimental data, assuming this reaction is dominated by quasifree single-nucleon knockout, and using an N* free width of 150 MeV. Differential and total cross sections are calculated for the exclusive reaction C13(π+,η)13N.