Evidence for fixed poles in two body meson baryon scattering is studied. The contributions of wrong signature fixed poles occur in wrong signature sum rules. Evaluated is the first wrong signature sum rule for the t-channel helicity flip amplitude in pion nucleon anti kaon nucleon charge exchange and in hypercharge exchange scatterings. According to recent theoretical analysis the J = O antikaon nucleon charge exchange wrong signature fixed pole is generated, via t-channel unitarity, from the pion nucleon one. Its existence implies a spin = O antikaon nucleon charge exchange right signature fixed pole. Evidence for the existence of a spin = O wrong signature fixed pole is found in all of them. It is also found that the nonperipheral resonances are mainly responsible for all fixed poles. (Author)
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