High-spin states in^(189)Pt are populated through the heavy-ion fusion-evaporation reaction^(176)Yb(18O,5n)^(189)Pt at 87 MeV beam energy.An array consisting of 13 HPGe detectors is used in conjunction with the plunge...High-spin states in^(189)Pt are populated through the heavy-ion fusion-evaporation reaction^(176)Yb(18O,5n)^(189)Pt at 87 MeV beam energy.An array consisting of 13 HPGe detectors is used in conjunction with the plunger device in CIAE.The lifetimes of two levels in the yrast band are determined by using the recoil distance Doppler shift method.The transition quadrupole moments Qt are extracted.The results show that the 17+/2 state has a much larger Qt value than that of the ground state,whereas the value deceases quickly with spin increasing.This may contribute to the shape driving effect of the quasi-neutron from the i_(13/2)orbital.展开更多
High spin states of the odd-odd nucleus 92Nb are investigated using the S2Se （14N, 4n）92Nb reaction at a beam energy of 54MeV. The level scheme of the 92Nb was extended up to Jπ=（16＋） at about 7.3 MeV and Jπ=（...High spin states of the odd-odd nucleus 92Nb are investigated using the S2Se （14N, 4n）92Nb reaction at a beam energy of 54MeV. The level scheme of the 92Nb was extended up to Jπ=（16＋） at about 7.3 MeV and Jπ=（21-） at about 9.7MeV. According to systematic analyses and a comparison with the neighboring nucleus, the higher spin states could be interpreted by the multi-particle excitations in the π（fs/2,P3/2,p1/2,gg/2）@v（p1/x,gg/2,d5/2, g7/2） configuration space.展开更多
Excited states of the odd-odd nucleus 122I are investigated via the fusion-evaporation reaction 116Cd(11B,5n)at a beam energy of 68 MeV.The two most strongly populated bands in 122I are observed up to excitation energ...Excited states of the odd-odd nucleus 122I are investigated via the fusion-evaporation reaction 116Cd(11B,5n)at a beam energy of 68 MeV.The two most strongly populated bands in 122I are observed up to excitation energies around 10.5 MeV.Their possible configurations at lower spins are assigned toπh_(11/2)■νh_(11/2) andπh_(11/2)■νd_(5/2) based on the observed population,B(M1)/B(E2)values,alignments and signature splitting.E1 transitions are observed connecting theπh_(11/2)■νd_(5/2) band to theπh_(11/2)■νh_(11/2) band,which may be evidence of octupole collectivity.Band terminations caused by the full alignment of the valence nucleons outside the 114Sn core are observed in both bands.展开更多
Excited states in^(120)I are investigated utilizing in-beam gamma-ray spectroscopy following the^(114)Cd(^(11)B,5n)reaction at 70 MeV bombarding energy.A level scheme is constructed with states up to 9 MeV.The levels ...Excited states in^(120)I are investigated utilizing in-beam gamma-ray spectroscopy following the^(114)Cd(^(11)B,5n)reaction at 70 MeV bombarding energy.A level scheme is constructed with states up to 9 MeV.The levels are classified into several bands and their possible configurations at low spins are discussed briefly.Based on the linking transitions between different bands at higher spins,the excitation energy of the previously reported T1/2=53 min isomer is ascertained to be 72 keV.Evidence showing the existence of an isomer at an excitation energy of 6.4 MeV is presented.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 11175259,11075214 and 10927507.
文摘High-spin states in^(189)Pt are populated through the heavy-ion fusion-evaporation reaction^(176)Yb(18O,5n)^(189)Pt at 87 MeV beam energy.An array consisting of 13 HPGe detectors is used in conjunction with the plunger device in CIAE.The lifetimes of two levels in the yrast band are determined by using the recoil distance Doppler shift method.The transition quadrupole moments Qt are extracted.The results show that the 17+/2 state has a much larger Qt value than that of the ground state,whereas the value deceases quickly with spin increasing.This may contribute to the shape driving effect of the quasi-neutron from the i_(13/2)orbital.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11075064, 10927507, 11075214, 10675171, 11175259.
文摘High spin states of the odd-odd nucleus 92Nb are investigated using the S2Se （14N, 4n）92Nb reaction at a beam energy of 54MeV. The level scheme of the 92Nb was extended up to Jπ=（16＋） at about 7.3 MeV and Jπ=（21-） at about 9.7MeV. According to systematic analyses and a comparison with the neighboring nucleus, the higher spin states could be interpreted by the multi-particle excitations in the π（fs/2,P3/2,p1/2,gg/2）@v（p1/x,gg/2,d5/2, g7/2） configuration space.
基金Supported by the National Natural Science Foundation of China(10675053)the National Basic Research Programme of China(2007CB815005)RFDP(20060183048)。
文摘Excited states of the odd-odd nucleus 122I are investigated via the fusion-evaporation reaction 116Cd(11B,5n)at a beam energy of 68 MeV.The two most strongly populated bands in 122I are observed up to excitation energies around 10.5 MeV.Their possible configurations at lower spins are assigned toπh_(11/2)■νh_(11/2) andπh_(11/2)■νd_(5/2) based on the observed population,B(M1)/B(E2)values,alignments and signature splitting.E1 transitions are observed connecting theπh_(11/2)■νd_(5/2) band to theπh_(11/2)■νh_(11/2) band,which may be evidence of octupole collectivity.Band terminations caused by the full alignment of the valence nucleons outside the 114Sn core are observed in both bands.
基金Supported by the National Natural Science Foundation of China under Grant No 10675053the National Basic Research Program of China under Grant No 2007CB815005the Research Fund for the Doctoral Program of Higher Education of China under Grant No 20120061110008.
文摘Excited states in^(120)I are investigated utilizing in-beam gamma-ray spectroscopy following the^(114)Cd(^(11)B,5n)reaction at 70 MeV bombarding energy.A level scheme is constructed with states up to 9 MeV.The levels are classified into several bands and their possible configurations at low spins are discussed briefly.Based on the linking transitions between different bands at higher spins,the excitation energy of the previously reported T1/2=53 min isomer is ascertained to be 72 keV.Evidence showing the existence of an isomer at an excitation energy of 6.4 MeV is presented.
