Band Interaction between Chiral Doublet Bands

Band interaction between the chiral doublet bands based on πh11/2？νh？111/2 configuration is investigated in the particle rotor model with different triaxial deformation γ. The variation of chiral partner states with γ values is understood qualitatively based on the basic picture of two interaction levels, which is confirmed further by the calculated overlap integral of wave functions at different γ values. It is found that the interaction strengths of chiral partner states are obviously different for odd spins and even ones.     

Structure of high spin states in 112In

The high spin states of ¹¹²In have been populated via the ¹¹⁰Pd(⁷Li,5n)¹¹²In reaction with a beam energy of 50 MeV. By analyzing the γ-γ coincidence relations and DCO ratios of γ transitions,A new level scheme of ¹¹²In including seventy-four new gamma transitions and six new bands up to the excitation energy of 6.8 MeV has been presented.     

实验探索原子核中手征与空间反射对称性的联立自发破缺

原子核的手征对称性和空间反射对称性研究是近来原子核结构研究的前沿热点问题,吸引了大量的实验和理论研究。通过在束伽玛谱学的实验方法,在原子核78Br中发现了两对宇称相反的手征双重带,以及它们之间表征八极关联的电偶极跃迁。这是首次在原子核中发现了八极关联的多重手征带,给出了原子核存在手征对称性和空间反射对称性联立自发破缺的实验证据。Spontaneous symmetry breaking is a fundamental concept in nature. Chiral Symmetry Breaking and reflection-asymmetry in nuclei has been a subject of intensive experimental and theoretical investigation. Two pairs of positive-and negative-parity doublet bands together with eight strong electric dipole transitions linking their yrast positive-and negative-parity bands have been identified in 78Br by means of in-beam gamma-ray spectroscopy techniques. These four rotational bands are suggested as multiple chiral doublet bands with octupole correlations. This observation indicates that nuclear chirality can be robust against the octupole correlations. It is of highly scientific interest to search for the chirality-parity quartet bands in nucleus with both stable triaxial and octupole deformations.     

Effects of(La,Sr) co-doping on electrical conduction and magnetic properties of BiFeO_3 nanoparticles

Multiferroic material as a photovoltaic material has gained considerable attention in recent years.Nanoparticles(NPs)La_(0.1)Bi_(0.9-x)Sr_xFeO_y(LBSF,x = 0,0.2,0.4) with dopant Sr~(2+)ions were synthesized by the sol–gel method.A systematic change in the crystal structure from rhombohedral to tetragonal upon increasing Sr doping was observed.There is an obvious change in the particle size from 180 nm to 50 nm with increasing Sr substitution into LBFO.It was found that Sr doping effectively narrows the band gap from～2.08 e V to～1.94 e V,while it leads to an apparent enhancement in the electrical conductivity of LBSF NPs,making a transition from insulator to semiconductor.This suggests an effective way to modulate the conductivity of BiFeO_(3-)based multiferroic materials with pure phase by co-doping with La and Sr at the A sites of BiFeO_3.     

Chiral doublet bands and energy-level crossing

Different definitions for chiral doublet bands based on excitation energies, B(E2) and B(M1) respectively are discussed in the triaxial particle rotor model. For the ideal chiral geometry, the selection rules of the electromagnetic transitions in different band definitions are illustrated. It is also shown that the energy-level crossings between chiral doublet bands may occur.     

Dynamic global load balancing strategy for cross stratum optimization of OpenFlow-enabled triple-M optical networks

With the emergence of high-bitrate applications, cross stratum optimization (CSO) attracts the interest of network operators because of its application in the joint optimization of optical networks and application stratum resources. Given the large-scale growth and high complexity of optical networks, achieving a more effective, accurate, and practical CSO becomes an important research focus. In this letter, we present a CSO-oriented, unified control architecture for OpenFlow-enabled triple-M optical networks. A novel dynamic global load balancing (DGLB) strategy with dynamic resource rating for CSO is presented based on the proposed architecture. The DGLB strategy is then compared with four other strategies by conducting experiments on a SOFT-based testbed with 1000 virtual nodes.     

126I高自旋态的认定

利用重离子融合蒸发反应¹²²Sn(¹¹B,5n2p)布居了双奇核¹²⁶I的激发态,首次建立了具有集体带结构特征的能级纲图,其中包括20条新γ跃迁.所建能级纲图的核素归属指定得到了核反应¹²⁴Sn(⁷Li,5n)的交叉支持.简单讨论了所建带结构的可能组态.     

Possible candidate nuclei for chirality-parity quartet bands

The potential energy surfaces of the even-even~(68-92)Se,~(112-150)Ba,and~(208-230)Ra isotopes are calculated using the macroscopic-microscopic method in a multidimensional space{α_(λ,μ)}including quadrupole(λ=2,μ=0,2)and octupole(λ=3,μ=0,1,2,3)degrees of freedom.The calculated results show that the even-even isotopes~(92)Se,~(112,114,144-150)Ba and~(220-228)Ra can exhibit the coexistence of triaxial and octupole deformations,thereby leading to simultaneous chiral and reflected symmetry breaking.Therefore,chirality-parity quartet bands are expected in these and their neighboring odd-A/odd-odd nuclei.     

πg9/2⊙νh11/2 doublet bands in A~100 mass region

Using the model with one particle and one hole coupled with a triaxial rotor, the πg^－1_9/2⊙νh_11/2 doublet bands in the A~100 mass region are studied, and compared with the πh_11/2⊙νh^－1_11/2 doublet bands. It is found that the calculated results for the configuration of πg^－1_9/2⊙νh_11/2 are very similar the results for a pure h_11/2 proton particle and a neutron quasiparticle with λ_n=ε₅. After including the pair correlation, the model describes the candidate chiral doublet bands in ¹⁰⁶Rh successfully, which supports the interpretation of chirality geometry.     

Shears bands in 112In

A new level scheme of ¹¹²In have been established up to 6.8 MeV in excitation energy and to a tentative spin of (21⁺) through the reaction ¹¹⁰Pd(⁷Li,5n)¹¹²In at a beam energy of 50 MeV. In-beam measurements involving γ-γ coincidences and directional correlation of oriented states were performed. M1 bands consisting of ΔI=1 dipole transitions have been observed. Possible quasiparticle configurations suggest that these bands are similar to the shears bands observed in Pb nuclei.