Partial-wave analysis of {\pi}-p {\to} {\eta}n and {\pi}-p {\to} K0{\Lambda} reactions

Abstract

We investigate the hadronic reactions {\pi}N {\to} {\eta}N and {\pi}N {\to} K{\Lambda} via single-energy partial-wave analyses in the c.m. energy range 1080 to 2100 MeV. Our results for the K{\Lambda} channel are consistent with prior works; however, for the {\eta}N channel our results differ significantly from previous energy-dependent partial-wave analyses that violate the S-matrix unitarity. We present the first (new) results of {\eta}N and K{\Lambda} partial-wave amplitudes constrained by a unitary energy-dependent model. We obtain excellent predictions of integrated cross sections for the two reactions from a global energy-dependent solution. Our results imply that the region just above S11 (1535) has a major contribution from P11 (1710) for {\pi}-p {\to} {\eta}n, whereas the large peak near 1700 MeV in {\pi}-p {\to} K0{\Lambda} is dominated by contributions from both S11 (1650) and P11 (1710).