Debye屏蔽自洽势下Au^(50+)离子的能级与振子强度  

THE ENERGY LEVELS AND OSCILLATOR STRENGTH OF A COMPLEX ATOM——Au 50+ IN A SELF CONSISTENT POTENTIAL

作　　者：冯蓉[1,2] 邹宇[1,2] 方泉玉 

机构地区：[1]中国工程物理研究院北京研究生部 [2]北京应用物理与计算数学研究所

出　　处：《物理学报》1998年第5期738-746,共9页Acta Physica Sinica

基　　金：国家高技术计划惯性约束聚变领域基金;国家自然科学基金

摘　　要：以惯性约束聚变实验中感兴趣的金的类铜离子（Ａｕ５０＋）为例，讨论了等离子体中自由电子对复杂原子中电子行为的影响．采用受Ｄｅｂｙｅ屏蔽的ＨａｒｔｒｅｅＦｏｃｋＳｌａｔｅｒ自洽势，计算了Ａｕ５０＋离子的主量子数ｎ从１到７的２８个本征态，得到了对应于一系列Ｄｅｂｙｅ长度Λ的能量本征值Ｅｎｌ，即轨道束缚能，和能级之间的光学振子强度．与类氢情况相似：自由电子的屏蔽作用使所有能级均从无屏蔽时的位置向连续态移动，即电离限下移；对于每个能量本征态（ｎ，ｌ），存在一个临界屏蔽长度Λ０（ｎ，ｌ），相应于该Λ０的轨道能Ｅｎｌ为零；当Λ值较小时，在较大ｎ处会出现能级交错．此外，用“外屏蔽”的概念，解释了在Λ＞５ａ０情况下，Ｄｅｂｙｅ屏蔽对Ａｕ５０＋离子激发能、振子强度、平均轨道半径等均不产生影响，而仅使各轨道能平移同一常数．Abstract The effects of free electrons in a plasma on a complex atom are discussed, here we are interested in the target ionAu 50+ in inertia confined fusion(ICF). The results are compared with those in the case of hydrogenic ions. Accurate numerical solutions have been obtained for Schrdinger's equation through Debye screened Hartree Fock Slater self consistent potential. Solutions have been computed for 28 eigenstates, 1s through n =7, l =6,yielding the energy eigenvalues for a wide range of Debye screening length Λ . As in the case of hydrogenic ions, under screening, all energy levels are shifted away from their unscreened values toward the continuum, that is, the ionization limits are shifted downward. Conclusions have been made that when Λ >5a 0, that is, in the weak screening case, Debye screening has little effect on oscillator strength, average obital radius, transition matrix elements, etc., of Au 50+ . For each ( n,l ) eigenstate, there is a finite value of screening length Λ 0(n,l) , for which the energy becomes zero. When Λ is sufficiently small, level crossing appears at high n satets. Optical oscillator strength for Au 50+ has also been calculated, the results are compared with those under unscreened potential.

关 键 词：Debye屏蔽 自洽势 金50 能级 振子强度 

分 类 号：O562.1[理学—原子与分子物理]