Results for energy levels, radiative rates, and collision strengths for transitions among the lowest 97 fine-structure levels belonging to the (1s²2s²2p⁶) 3s²3p², 3s3p³, 3s²3p3d, 3p⁴, 3s3p²3d and 3s²3d² configurations of Fe XIII were recently reported by us [1], and in this work we present our results for excitation rate coecients. The most recent available results for Fe XIII are of Gupta & Tayal (GT: [2]). They have reported energy levels, radiative rates, and collision strengths (Ω) for transitions among 26 fine-structure levels of the 3s²3p², 3s3p³ and 3s²3p3d configurations. They also resolved resonances and reported results for effective collision strengths (Υ) at temperatures below 5×10⁶ K. They included configuration interaction (CI) for generating wavefunctions, and one-body relativistic operators for calculating Ω. Therefore, their results should be the most reliable available today. However, in a recent paper Landi [3] has emphasized a need for fresh calculations, because electron densities derived from line ratios calculated from the atomic data of GT and earlier data of Fawcett & Mason (FM: [4]) differ by a factor of two, and hence provide different results for plasma diagnostics. Therefore, we aim to assess the accuracy of the available data by performing an independent calculation. We have adopted the GRASP [5] and DARC [6] programs for the computations of wavefunctions and Ω, respectively. Thus our calculations are fully relativistic in the jj coupling scheme. Our results of Ω [1] were in broad agreement with those of GT, and the differences, if any, were in accordance with the wavefunctions. However, the corresponding results of FM were found to be deficient. For forbidden transitions, their values of Ω are underestimated, whereas for the allowed transitions they are overestimated. Additionally, for some of the allowed transitions their results of Ω are not in accordance with their corresponding f- values. Our calculations for Ω in thresholds region are nearly complete, and the data are being analyzed. We hope to present comparisons with the Υ results of GT during the conference. This work has been financed by EPSRC, PPARC and AWE Aldermaston of UK.

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