Using ab initio molecular-dynamics simulations combined with linear-response theory, we studied the x-ray absorption near-edge spectra (XANES) of a two-temperature dense copper plasma. As the temperature increases, XANES spectra exhibit a pre-edge structure balanced by a reduction of the absorption just behind the edge. By performing systematic simulations for various thermodynamic conditions, we establish a formulation to deduce the electronic temperature $T_e$ directly from the spectral integral of the pre-edge that can be used for various thermodynamic conditions encountered in a femtosecond heating experiment where thermal nonequilibrium and expanded states have to be considered.

中文翻译：

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使用ab引发模拟了解两温热致密铜的XANES光谱

使用从头算分子动力学模拟与线性响应理论相结合的方法，我们研究了两温致密铜等离子体的x射线吸收近边缘光谱（XANES）。随着温度升高，XANES光谱显示出边缘前的结构，该边缘前的结构通过边缘后部的吸收减少而达到平衡。通过对各种热力学条件进行系统模拟，我们建立了一个公式来推导电子温度${Ť}_{Ë}$ 直接从可用于飞秒加热实验中遇到的各种热力学条件的前缘光谱积分中，必须考虑热不平衡和膨胀态。