The reaction p(e,e′ π+)X0 was studied with two high-resolution magnetic spectrometers to search for narrow baryon resonances. A missing mass resolution of 2.0 MeV was achieved. A search for structures in the mass region of 0.97X0<1.06 GeV yielded no significant signal. The yield ratio of p(e,e′ π+)X0/p(e,e′ π+)n was determined to be (-0.35±0.35) × 10-3 at 1.004 GeV and (0.34±0.42) × 10-3 at 1.044 GeV. This measurement clearly demonstrated the potential of high-resolution missing mass searches in coincidence experiments.
