论文标题
$^{100-140} $ sn同位素链中磁性偶极强度的演变和核子G因子的淬火
The evolution of magnetic dipole strength in $^{100-140}$ Sn isotope chain and quenching of nucleon g factors
论文作者
论文摘要
沿同位素链的电磁过渡的演变对于核结构和动力学以及R过程核合成尤其重要。最近对均匀的无弹性质子散射的测量均匀，什至$^{112-124} $ sn同位素对E1和M1强度分布的同位素依赖性提供了一种新颖的见解。我们基于相对论核能密度功能，从理论的角度研究了M1的M1转变。 M1过渡强度分布的特征是单个和双峰结构之间的相互作用，这可以从单粒子状态的演变，由配对相关性控制的职业以及所涉及的两数quasiparticle跃迁中理解。结果表明，B（M1）过渡强度的模型计算与实验之间的差异要比以前已知要大大降低，并且对于复制M1转换强度的实验数据所需的自由核子的G-FAICTORS的淬火量$ G_ {EFF}/G_ {free}/g_ {free} $ = 0.80-0-0-0.93。由于在非弹性质子散射测量中可能缺少中子阈值的B（M1）强度中的某些强度，因此需要进一步的实验研究以确认是否仅在有生物核中应用裸g因子的少量修饰。
The evolution of electromagnetic transitions along isotope chains is of particular importance for the nuclear structure and dynamics, as well as for the r-process nucleosynthesis. Recent measurement of inelastic proton scattering on even-even $^{112-124}$Sn isotopes provides a novel insight into the isotopic dependence of E1 and M1 strength distributions. We investigate M1 transitions in even-even $^{100-140}$Sn isotopes from a theoretical perspective, based on relativistic nuclear energy density functional. The M1 transition strength distribution is characterized by an interplay between single and double-peak structures, that can be understood from the evolution of single-particle states, their occupations governed by the pairing correlations, and two-quasiparticle transitions involved. It is shown that discrepancy between model calculations and experiment on B(M1) transition strength is considerably reduced than previously known, and the quenching of the g-factors for the free nucleons needed to reproduce the experimental data on M1 transition strength amounts $g_{eff}/g_{free}$=0.80-0.93. Since some of the B(M1) strength above the neutron threshold may be missing in the inelastic proton scattering measurement, further experimental studies are required to confirm if only small modifications of the bare g-factors are actually needed when applied in finite nuclei.
