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Gamma-ray angular distributions in oriented 92 Mo produced via the 6 Li+ 89 Y reaction were studied in this work. The characteristic γ rays in 92 Mo were measured by means of the GALILEO array, which is composed of 25 Compton-suppressed HPGe detectors arranged in a nearly 2 π geometry. A detailed analysis of the spin-alignment attenuation factors ( α 2 ) for different excited states in 92 Mo was performed, by analyzing the measured angular distribution coefficients of several pure-E2 transitions. The relationship between α 2 and the spin was established in 92 Mo and the 244-keV transition between the 5 1 - and 4 1 + states resulted to have a E1 + M2 character with a mixing ratio (δ ) of - 0. 05 - 0.06 + 0.05 , consistent with shell model calculations. [ABSTRACT FROM AUTHOR]

Enriched targets of 116,118,120,122,124SnO2 were bombarded with proton and deuteron beams, and the angular distributions of (p,d) and (d,p) on tin isotopes were accurately measured using the high-precision Q3D magnetic spectrograph at the Beijing HI-13 tandem accelerator of the China Institute of Atomic Energy. Distorted-wave Born approximation calculations were performed to extract the neutron spectroscopic factors (SFs) using two different sets of systematic optical potential parameters for these neutron transfer reactions. The SFs of 116-125Sn were obtained and compared to previous values. Our results are consistent with the average of the previous data within the error range. It is worth noting that the reaction products corresponding to 119SnG.S. and 119Sn*0.024, to 123SnG.S. and 123Sn*0.025, and to 125SnG.S. and 125Sn*0.028 were first distinguished by the present experiment; therefore, our results of the low lying states of 119,123,125Sn are more reliable. However, the first excited state of 121Sn is only 0.006 MeV; we failed to identify the products that correspond to the ground state and the first excited state, and the extracted SFs of 120SnG.S.⊗n→121Sn0.006. and 121Sn0.006⊗n→122SnG.S are not reliable. A simple linear formula was used to analyze the relationship of SFs with neutron separation energy Sn(N) and the even-A Sn pairing gap Δ(N), and SFs are found to be positively correlated to Sn(N) and Δ(N). [ABSTRACT FROM AUTHOR]

Excited states of the odd-odd nucleus 158Tb have been studied via the 154Sm(7Li ,3n) 158Tb reaction at a beam energy of 27 MeV. The new level scheme of 158Tb involving a positive parity rotational band is established up to excitation energy ∼2.3 MeV and spin ∼17ħ. By comparing with the rotational bands in the neighboring nuclei 157Tb and 157Gd, the configuration was tentatively assigned as πd5/2⊗ vi13/2 , and the phenomenon of signature inversion is discussed. [ABSTRACT FROM AUTHOR]

The measurement of one-neutron stripping cross sections for the 89Y(6Li,5Li)90Y* reaction at 22 MeV and 34 MeV is reported, using both in-beam and off-beam γ-ray spectroscopy methods. Characteristic γ lines of 90Y are clearly identified by both the γ-γ and proton-γ coincidence methods. The obtained cross section of one-neutron stripping at 34 MeV is found to be much smaller than that at 22 MeV. The one-neutron stripping cross sections measured for this system have the same order of magnitude as the one measured for the same reaction for the 6Li+96Zr system at energies around the Coulomb barrier. Parameter-free coupled reaction channel calculations agree quite well with the experimental data. Theoretical study of the effect of the one-neutron transfer on the elastic total fusion cross section is performed. [ABSTRACT FROM AUTHOR]