High spin states of the odd-proton nucleus ^(167)Lu have been studied via ^(152)Sm(^(19)F,4n)^(167)Lu reaction at 87MeV beam energy.A weakly populated new rotationa1 band has been observed and assigned as i13/2 proton...High spin states of the odd-proton nucleus ^(167)Lu have been studied via ^(152)Sm(^(19)F,4n)^(167)Lu reaction at 87MeV beam energy.A weakly populated new rotationa1 band has been observed and assigned as i13/2 proton 1/2^(+)[660] band.This new band and the 1/2^(+)[660] band in ^(171)Ta from the early work are classified as superdeformed bands with triaxiality.展开更多
High spin states in ^(90)Mo have been populated through the ^(59)Co (^(35)Cl,2p2n) 90Mo reaction at beam energy of 116 MeV. Level lifetimes of the positive-parity decay sequence are measured by using the Doppler shift...High spin states in ^(90)Mo have been populated through the ^(59)Co (^(35)Cl,2p2n) 90Mo reaction at beam energy of 116 MeV. Level lifetimes of the positive-parity decay sequence are measured by using the Doppler shift attenuation method. It is observed that the M1 transition strengths show a substantial enhancement at high spin. This behaviour may be related to occupation of high Ω orbitals by a pair of g9/2 protons. A deformed shape with oblate is suggested above the 13^(+) state.展开更多
Transition energies of three triaxial superdeformed bands in 86Zr were fitted by the power-series expansion of spin I in odd powers of rotationalfrequeney ψ and by the two-parameter expression for rotational spectra....Transition energies of three triaxial superdeformed bands in 86Zr were fitted by the power-series expansion of spin I in odd powers of rotationalfrequeney ψ and by the two-parameter expression for rotational spectra. Level spins of these bands were assigned by means of the least-squares fits.展开更多
High-spin states in^(84)Rb have been studied by using the^(70)Zn(^(18)O,p3n)^(84)Rb reaction at a beam energy of 75 MeV.Theγ-γcoincidence,excitation function and ratios for directional correlation of oriented states...High-spin states in^(84)Rb have been studied by using the^(70)Zn(^(18)O,p3n)^(84)Rb reaction at a beam energy of 75 MeV.Theγ-γcoincidence,excitation function and ratios for directional correlation of oriented states were performed.A new level scheme was established in which the positive and negative parity bands have been extended up to 17^(+)and 17^(-)with excitation energy about 7MeV.The signature splitting and signature inversion of the positive parity yrast bands were observed and are discussed.展开更多
Structure of high spin states in ^(87)Zr was studied through the reaction ^(59)Co(^(32)S,3pn)^(87)Zr at a beam energy of 118 MeV using in-beam γ-ray spectroscopic method.Measurement of γ-γ coincidence was performed...Structure of high spin states in ^(87)Zr was studied through the reaction ^(59)Co(^(32)S,3pn)^(87)Zr at a beam energy of 118 MeV using in-beam γ-ray spectroscopic method.Measurement of γ-γ coincidence was performed,and directional correlation orientation ratios of someγrays were determined.The level scheme of ^(87)Zr was established up to spin(37/2^(+))and(43/2^(-)).Many previously unknown states have been observed.Comparison with neighboring isotones indicates that the effect of neutron on nuclear structure property is predominant compared to proton,and there is a tendency of reduction in band crossing frequency with increasing proton number.展开更多
The high-spin states of 160Lu are populated by the fusion-evaporation reaction 144Sm(19F,3n)160 Lu at beam energies of 90 and 106 Me V.A new level scheme of 160Lu is established.A possible isomeric state based on the ...The high-spin states of 160Lu are populated by the fusion-evaporation reaction 144Sm(19F,3n)160 Lu at beam energies of 90 and 106 Me V.A new level scheme of 160Lu is established.A possible isomeric state based on the πh11/2 (0) υh9/2 configuration is observed.The new decoupled band with the configuration of πd3/2[411]1/2^(+) (0)υi13/2[660] 1/2^(+) is established,and the configurations of these similar decoupled bands in the neighboring odd-odd 162-166 Lu nuclei are suggested.A positive parity coupled band is assigned as the πd5/2[402]5/2^(+)(0)υi13/2[660]1 /2^(+)configuration.展开更多
The level states of the nucleus ^(124)Cs have been populated through the ^(116)Sn(^(11) B,3n)reaction at a beam energy of 45MeV,provided by the HI-13 tandem accelerator of the China Institute of Atomic Energy.A number...The level states of the nucleus ^(124)Cs have been populated through the ^(116)Sn(^(11) B,3n)reaction at a beam energy of 45MeV,provided by the HI-13 tandem accelerator of the China Institute of Atomic Energy.A number of low-lying states are constructed.The level states in theπh_(11/2)νg_(7/2) side band are extended down to lower spin by one h.The level energies and spins in the rotational bands are determined through the establishment of various connections,which confirm the spin assignment of the yrast band in ^(124)Cs based on excitation energy systematics.It is revealed that with the present spin assignment,theπh_(11/2)νg_(7/2) side band shows signature inversion at low-spin region and the inversion occurs at a spin of about 16h.展开更多
High-spin states in the odd-proton nucleus^(135)pm have been investigated using the^(107)Ag(^(32)S,2p2n)^(135)pm reaction.Seven rotational bands have been observed in^(135)pm.The yrast band based on a decoupled h_(11/...High-spin states in the odd-proton nucleus^(135)pm have been investigated using the^(107)Ag(^(32)S,2p2n)^(135)pm reaction.Seven rotational bands have been observed in^(135)pm.The yrast band based on a decoupled h_(11/2)proton is found to have a band crossing in ω_(c)~0.43 MeV/h.Two positive-parity bands based on the two signature components of the πg_(7/2)5/2^(+)[413]Nilsson orbital have been observed in the main sidebands.The favoured band with(π,α)=(+,1/2)has been shown to populate below the first pair of proton alignment.Both bands have shown upbend at ω_(1)~0.26 MeV/h and ω_(2)~0.43 MeV/h.These crossing frequencies can be attributed to the decoupling of the first pair of h_(11/2) quasi-proton and h_(11/2) quasi-neutron,respectively.Four weaker bands have been observed in sidebands too.Among them,two states are possibly built on aπd_(5)/23/2^(+)[411]configuration.展开更多
The high-spin states of the odd-odd nucleus 170Ta have been studied by the 150Gd(19F,4n)170Ta reaction at the beam energy of 97 MeV.The α=1 sequence of the semi-decoupled band has been pushed to higher-spin states an...The high-spin states of the odd-odd nucleus 170Ta have been studied by the 150Gd(19F,4n)170Ta reaction at the beam energy of 97 MeV.The α=1 sequence of the semi-decoupled band has been pushed to higher-spin states and the signature inversion point was observed at 19.5ħ.The results are compared with those of the neighboring odd-odd nuclei.展开更多
High-spin states of^(119)Xe have been investigated by in-beam γ-ray spectroscopy via the reaction of ^(16)O bombarding a ^(106)Cd target at beam energies of 67-80MeV. No enhanced E1 transition was observed, the non-e...High-spin states of^(119)Xe have been investigated by in-beam γ-ray spectroscopy via the reaction of ^(16)O bombarding a ^(106)Cd target at beam energies of 67-80MeV. No enhanced E1 transition was observed, the non-existence of octupole correlations in ^(119) Xe.展开更多
Mean lifetimes of the h_(11/2) quasineutron band in 129Ce were measured by using the Doppler shift attenuation method in connection with the reaction ^(116)Sn(^(l6)O,3n)^(129)Ce at a bombarding energy of 73MeV.The dat...Mean lifetimes of the h_(11/2) quasineutron band in 129Ce were measured by using the Doppler shift attenuation method in connection with the reaction ^(116)Sn(^(l6)O,3n)^(129)Ce at a bombarding energy of 73MeV.The data indicate that transition quadrupole moment of ^(129)Ce is smaller than that of 128Ce.This reduction in collectivity caused by the addition of an h_(11/2) neutron can be interpreted as due to triaxiality induced byγdriving effect.展开更多
Lifetimes of the high spin states in the negative parity band of ^(126)Ba were measured by using the Doppler shift attenuation method in conjunction with the reaction ^(116)Sn(^(16)O,2p4n)^(126) Ba at a beam energy of...Lifetimes of the high spin states in the negative parity band of ^(126)Ba were measured by using the Doppler shift attenuation method in conjunction with the reaction ^(116)Sn(^(16)O,2p4n)^(126) Ba at a beam energy of 73 MeV.This band shows a typically collective behavior and possesses a near-axial prolate shape with a deformation parameter β_(2)=0.27±0.01 and triaxiality γ~-5°.展开更多
基金Supported by the National Natural Science Foundation of Chinathe Science Foundation of Nuclear Industry of China.
文摘High spin states of the odd-proton nucleus ^(167)Lu have been studied via ^(152)Sm(^(19)F,4n)^(167)Lu reaction at 87MeV beam energy.A weakly populated new rotationa1 band has been observed and assigned as i13/2 proton 1/2^(+)[660] band.This new band and the 1/2^(+)[660] band in ^(171)Ta from the early work are classified as superdeformed bands with triaxiality.
基金Supported by the National Natural Science Foundation of China under Grant Nos.19675067 and 19975070.
文摘High spin states in ^(90)Mo have been populated through the ^(59)Co (^(35)Cl,2p2n) 90Mo reaction at beam energy of 116 MeV. Level lifetimes of the positive-parity decay sequence are measured by using the Doppler shift attenuation method. It is observed that the M1 transition strengths show a substantial enhancement at high spin. This behaviour may be related to occupation of high Ω orbitals by a pair of g9/2 protons. A deformed shape with oblate is suggested above the 13^(+) state.
文摘Transition energies of three triaxial superdeformed bands in 86Zr were fitted by the power-series expansion of spin I in odd powers of rotationalfrequeney ψ and by the two-parameter expression for rotational spectra. Level spins of these bands were assigned by means of the least-squares fits.
基金Supported by the National Natural Science Foundation of China under Grant No.19635030the Science Foundation of the Nuclear Industry of China.
文摘High-spin states in^(84)Rb have been studied by using the^(70)Zn(^(18)O,p3n)^(84)Rb reaction at a beam energy of 75 MeV.Theγ-γcoincidence,excitation function and ratios for directional correlation of oriented states were performed.A new level scheme was established in which the positive and negative parity bands have been extended up to 17^(+)and 17^(-)with excitation energy about 7MeV.The signature splitting and signature inversion of the positive parity yrast bands were observed and are discussed.
基金Supported by the National Natural Science Foundation of China under Grant No.19675067.
文摘Structure of high spin states in ^(87)Zr was studied through the reaction ^(59)Co(^(32)S,3pn)^(87)Zr at a beam energy of 118 MeV using in-beam γ-ray spectroscopic method.Measurement of γ-γ coincidence was performed,and directional correlation orientation ratios of someγrays were determined.The level scheme of ^(87)Zr was established up to spin(37/2^(+))and(43/2^(-)).Many previously unknown states have been observed.Comparison with neighboring isotones indicates that the effect of neutron on nuclear structure property is predominant compared to proton,and there is a tendency of reduction in band crossing frequency with increasing proton number.
基金Partially supported by the National Natural Science Foundation of China under Grant Nos 11075064 and 21101129the National Basic Research Program of China under Grant No 2007CB815005the Specialized Research Fund for the Doctoral Program of Higher Education of China under Grant No 20050183008.
文摘The high-spin states of 160Lu are populated by the fusion-evaporation reaction 144Sm(19F,3n)160 Lu at beam energies of 90 and 106 Me V.A new level scheme of 160Lu is established.A possible isomeric state based on the πh11/2 (0) υh9/2 configuration is observed.The new decoupled band with the configuration of πd3/2[411]1/2^(+) (0)υi13/2[660] 1/2^(+) is established,and the configurations of these similar decoupled bands in the neighboring odd-odd 162-166 Lu nuclei are suggested.A positive parity coupled band is assigned as the πd5/2[402]5/2^(+)(0)υi13/2[660]1 /2^(+)configuration.
基金Supported by the National Natural Science Foundation of China under Grant No.19775019.
文摘The level states of the nucleus ^(124)Cs have been populated through the ^(116)Sn(^(11) B,3n)reaction at a beam energy of 45MeV,provided by the HI-13 tandem accelerator of the China Institute of Atomic Energy.A number of low-lying states are constructed.The level states in theπh_(11/2)νg_(7/2) side band are extended down to lower spin by one h.The level energies and spins in the rotational bands are determined through the establishment of various connections,which confirm the spin assignment of the yrast band in ^(124)Cs based on excitation energy systematics.It is revealed that with the present spin assignment,theπh_(11/2)νg_(7/2) side band shows signature inversion at low-spin region and the inversion occurs at a spin of about 16h.
基金Supported by the National Natural Science Foundation of China under Grant No.19635030the Science Foundation of the Nuclear Industry of China。
文摘High-spin states in the odd-proton nucleus^(135)pm have been investigated using the^(107)Ag(^(32)S,2p2n)^(135)pm reaction.Seven rotational bands have been observed in^(135)pm.The yrast band based on a decoupled h_(11/2)proton is found to have a band crossing in ω_(c)~0.43 MeV/h.Two positive-parity bands based on the two signature components of the πg_(7/2)5/2^(+)[413]Nilsson orbital have been observed in the main sidebands.The favoured band with(π,α)=(+,1/2)has been shown to populate below the first pair of proton alignment.Both bands have shown upbend at ω_(1)~0.26 MeV/h and ω_(2)~0.43 MeV/h.These crossing frequencies can be attributed to the decoupling of the first pair of h_(11/2) quasi-proton and h_(11/2) quasi-neutron,respectively.Four weaker bands have been observed in sidebands too.Among them,two states are possibly built on aπd_(5)/23/2^(+)[411]configuration.
基金Supported by the National Natural Science Foundation of China under Grant Nos.19635030 and 19675007.
文摘The high-spin states of the odd-odd nucleus 170Ta have been studied by the 150Gd(19F,4n)170Ta reaction at the beam energy of 97 MeV.The α=1 sequence of the semi-decoupled band has been pushed to higher-spin states and the signature inversion point was observed at 19.5ħ.The results are compared with those of the neighboring odd-odd nuclei.
基金Supported by the Chinese Academy of Sciences and the National Natural Science Foundation of Chins under Grant Nos.19675052,19635030 and 19805011.
文摘High-spin states of^(119)Xe have been investigated by in-beam γ-ray spectroscopy via the reaction of ^(16)O bombarding a ^(106)Cd target at beam energies of 67-80MeV. No enhanced E1 transition was observed, the non-existence of octupole correlations in ^(119) Xe.
基金Supported by the National Natural Science Foundation of China under Grant No.19675067the Science Foundation'of Nuclear Industry of China under Grant No.H7196A0115。
文摘Mean lifetimes of the h_(11/2) quasineutron band in 129Ce were measured by using the Doppler shift attenuation method in connection with the reaction ^(116)Sn(^(l6)O,3n)^(129)Ce at a bombarding energy of 73MeV.The data indicate that transition quadrupole moment of ^(129)Ce is smaller than that of 128Ce.This reduction in collectivity caused by the addition of an h_(11/2) neutron can be interpreted as due to triaxiality induced byγdriving effect.
基金Supported by the National Natural Science Foundation of China under Grant No.19675067the Science Foundation of Nuclear Industry of China under Grant No.H7196A0115.
文摘Lifetimes of the high spin states in the negative parity band of ^(126)Ba were measured by using the Doppler shift attenuation method in conjunction with the reaction ^(116)Sn(^(16)O,2p4n)^(126) Ba at a beam energy of 73 MeV.This band shows a typically collective behavior and possesses a near-axial prolate shape with a deformation parameter β_(2)=0.27±0.01 and triaxiality γ~-5°.
