^85Zr的高自旋态和磁转动带研究

质量数80区的过渡性核表现了集体性和单粒子性的能级结构。对质子数Z为37～40、中子数N=45的原子核,如81Kr,87Mo核,在中低自旋时显示了单粒子特性,而在高自旋态时表现出较多的集体性。 近些年来,在过渡区在束γ谱学,如83Rb、83Y等核研究中,观察到了一串建立在较高K态的增强的△I=1的M1跃迁。它被认为是一种新的激发模式,叫做磁转动带。我们对85Zr的研究目的,一是将其能级推到更高自旋,另一个是寻找该核的磁转动带。     

Magnetic Dipole Band in 113In

High spin states in the odd-A nucleus 113In have been investigated using the re-action 110Pd(7Li,4n) at a beam energy of 50 MeV. A new positive parity dipole band with the configuration of π(g9/2)-1ν(h11/2)2ν(g7/2)2 is established. The effective interaction V(θ) values of this band have been successfully described by a semiclassical geometric model based on shear mechanism, which show that the dipole band has the characteristics of magnetic rotation. In addition the collective rotational angular momentum for this band is extracted. The results show that the core contribution increases gradually with the increase of the rotation frequency.     

High-k Structures in (124)～Cs

High spin states in the odd-odd nucleus 124 Cs have been investigated through the fusion-evaporation reaction 116 Sn(11 B,3n) 124 Cs with a beam energy of 45 MeV.A new rotational band is established and assigned as the high-k configuration of πg 9/2 [404]9/2 +νh 11/2 [523]7/2.Some structures linking to this band have also been observed.According to the results of the excitation energy systematics,the lowest level of this band is assigned as 9,and the 8 isomer bandhead has not been observed.Another isomer with a half life of 6.3 s has also been observed with its new decay paths established.Its excitation energy is raised by 79 keV,but its I π is not changed.     

Yrast Band in 122I and Band Termination

High spin states of the odd-odd nucleus 122 I have been investigated via the fusion-evaporation reaction 116 Cd(11B, 5n) at a beam energy of 68 MeV. The yrast band is extended up to Iπ=(29+). The band termination at Iπ=(22+) reported in previous studies is confirmed and interpreted as arising from a shape change from collective prolate to noncollective oblate according to Total-Routhian-Surface (TRS) calculations. In addition, the Iπ=(29+) state is assigned to the [πh11/2(πg7/2)2]23/2-[(νh11/2)3(νd5/2)2]35/2-configuration corresponding to the full alignment of all valance nucleons outside the semi-closed shell.     

New Structures in Odd-Odd 120I

The excited states of the doubly-odd 120 I have been investigated via the 110Pd(14N,4n) and the 114Cd(10B,4n) reactions at beam energies of 64 MeV and 48 MeV, re-spectively. The previously known bands are extended, and a new band structure is established. The yrast band is assigned to the πh11/2νh11/2 configuration instead of the previously as-signed πg7/2νh11/2 configuration. Possible configurations of the other observed bands are also discussed.     

25 ^126I高自旋态的首次观测

本工作对双奇核^126I的高自旋态进行了研究。Burde等曾利用轻粒子核反应对^126I核的能级结构进行了研究，而本工作则是通过重离子融合蒸发反应对该核进行研究。