Proton Resonances Spectroscopy in PHOSPHORUS-29

Proton elastic scattering on ^ {28}Si was measured with good beam energy resolution in the proton energy range E_ {rm p} = 1.4 to E_ {rm p} = 3.75 MeV, and proton inelastic scattering on ^{28}Si was studied from E_{rm p} = 3.0 to 3.75 MeV. A resonance not previously seen in the elastic scattering channel was observed at E_{rm p} = 2.287 MeV; the elastic width was measured to be 80 eV. The resonance at E_{rm p} = 3.102 MeV had been assigned J^pi = 5/2^- from previous proton elastic and inelastic scattering data. From the present measurements the spin and parity of the resonance is J^ pi = 7/2^-. The capture yields were used to locate extremely weak resonances near E_{rm p} = 1.377 MeV and 2.630 MeV. Upper limits for the elastic widths of the resonances at E_{rm p } = 1.377 MeV and 2.630 MeV are 2 eV; this reduced the previous upper limits for the elastic widths by 3 orders of magnitude. The resonance at E_ {rm p} = 2.630 MeV has an inelastic width of 10 eV. Spectroscopic factors for the resonances in ^{29}P were compared with those for the levels in the parent nucleus ^{29}Si. Large Thomas-Ehrman shifts are observed for a number of the mirror levels.