Two-quasiproton states in 190Os and 192Os studied with the (t,α) reaction

Level structures up to 3000 keV in 190Os and 192Os have been studied using the 191Ir and 193Ir (t,α) proton pickup reactions with 15 MeV tritons. The α-particle spectra were obtained with the quadrupole-dipole-dipole-dipole magnetic spectrometer with peak widths of approx.11 keV (full width half maximum). This reaction strongly excites the I,K/sup [/ = 4,4+ levels at 1162 keV in 190Os and at 1070 keV in 192Os, which were previously interpreted as two-phonon γ-vibrational states. The large two-quasiproton amplitude is reasonably explained by assuming single-phonon hexadecapole vibrations which involve the ]5/2 [402], 3/2 [402]] configuration. Many two-quasiproton states are observed in the energy region 2000--3000 keV. The strongest peaks found at an excitation energy of approx.2600 keV in both 190Os and 192Os may be the remaining portions of the two-quasiproton ]5/2 [402], 3/2 [402]]/sub I/,Kπ/sub tsts4,4/+ states