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Searches have been performed for neutrinoless muon-electron conversion and muon-positron conversion using a time projection chamber. An upper limit on the branching ratio for the coherent reaction R(jd ~+Ti-e~+Ti) <4.6xl0~1 2 [90% confidence level (C.L.)] relative to ordinary muon capture was obtained. For the process n ~ +Ti-* e + + Ca no events were observed for positron momenta p > 96 MeV/c leading to an upper limit on the partial branching ratio relative to ordinary muon capture r p>9 6(M~+Ti^e + + Ca)/rO*-+Ti-capture) <9xl0~1 2 (90% C.L.). With the assumption of a giant-resonance-excitation model the integrated limit would be < 1.7x 10 ~1 0 (90% C.L.).

The data for the total cross section for p + p +rf + d are reanalyzed to obtain the component for s-wave pion production near threshold. This comprehensive analysis yields a value which is compatible with other low-energy pion-nucleon reactions.