First Experimental Constraints On The Interference Of 3/2(+) Resonances In The F-18(P,Alpha)O-15 Reaction

The interference effects among J(pi)=3/2(+) resonances in the F-18+p system have not been previously measured. R-matrix calculations show that the cross sections above the E-c.m.=665 keV resonance are sensitive to the interference between the E-c.m.=8, 38, and 665 keV resonances. An excitation function for the H-1(F-18,alpha)O-15 reaction has been measured in the energy range of E-c.m.=663-877 keV using radioactive F-18 beams at the Holifield Radioactive Ion Beam Facility (HRIBF). By comparing the observed cross sections with the R-matrix calculations, we provide the first experimental constraints on the interference. Upper limits on proton widths (Gamma(p)) of the E-c.m.=827 and 842 keV resonances have been set as well.