Chen Guo Xin, Pradhan Anil K
Department of Astronomy, The Ohio State University, Columbus, Ohio 43210, USA.
Phys Rev Lett. 2002 Jul 1;89(1):013202. doi: 10.1103/PhysRevLett.89.013202. Epub 2002 Jun 17.
New theoretical results from large-scale relativistic close coupling calculations reveal the precise effect of resonances in collisional excitation of x-ray lines of Ne-like Fe XVII. By employing the Breit-Pauli R-matrix method and an 89-level eigenfunction expansion, including up to n = 4 levels, significant resonance enhancement of the collision strengths of forbidden and intercombination transitions is shown. The present results should help resolve long-standing discrepancies; in particular, the present line ratios of three benchmark diagnostic lines 3C, 3D, and 3E at 15.014, 15.265, and 15.456 A, respectively, are in excellent agreement with two independent measurements on electron-beam ion traps. Strong energy dependence in cross sections due to resonances is demonstrated.
大规模相对论性紧密耦合计算得出的新理论结果揭示了类氖铁 XVII 的 X 射线谱线碰撞激发中共振的精确效应。通过采用 Breit-Pauli R 矩阵方法和 89 能级本征函数展开（包括高达 n = 4 的能级），展示了禁戒跃迁和组合跃迁碰撞强度的显著共振增强。目前的结果应有助于解决长期存在的差异；特别是，目前分别位于 15.014、15.265 和 15.456 Å 的三条基准诊断谱线 3C、3D 和 3E 的线比，与电子束离子阱的两项独立测量结果高度吻合。证明了由于共振导致的截面强烈能量依赖性。
