We report measurements of $K$-shell fluorescence lines induced by fast electrons in ramp-compressed Co targets. The fluorescence emission was stimulated by fast electrons generated through short-pulse laser-solid interaction with an Al target layer. Compression up to $2.1\times$ solid density was achieved while maintaining temperatures well below the Fermi energy, effectively removing the thermal effects from consideration. We observed small but unambiguous redshifts in the $K\beta$ fluorescence line relative to unshifted Cu $K\alpha$. Redshifts up to 2.6 eV were found to increase with compression and to be consistent with predictions from self-consistent models based on density-functional theory.

中文翻译：

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在高达8 Mbar的斜压压缩钴中测量压力引起的Kβ线位移

我们报告的测量 $ķ$快速电子在斜坡压缩的Co靶中诱导的壳荧光线。通过与Al目标层的短脉冲激光-固体相互作用产生的快速电子激发了荧光发射。压缩高达$2.1\times$在保持温度远低于费米能量的同时达到了固体密度，有效地消除了热影响。我们观察到小但明确的红移$ķ\beta$ 相对于未移动Cu的荧光线 $ķ\alpha$。发现高达2.6 eV的红移随压缩而增加，并且与基于密度泛函理论的自洽模型的预测一致。