X-ray absorption and core-ionization spectra of molecules pumped by two coherent infrared pulses with different polarizations are studied theoretically. We have found a sensitivity of the vibrational profile of x-ray probe spectra to polarizations of the IR and x-ray pulses. This polarization dependence is qualitatively different for x-ray absorption and x-ray photoelectron spectra. Measurements of this polarization dependence allow to select the difference in Franck-Condon distributions from the lowest and pumped vibrational levels of the electronic ground state. The proposed technique is exemplified numerically using x-ray absorption spectra of the pumped CO molecule. We also show that this kind of pump-probe spectroscopy can enable studies of the dynamics of molecular rotation.

中文翻译：

---

偏振敏感的红外泵浦-x射线探针光谱

从理论上研究了两个不同偏振的相干红外脉冲泵浦分子的X射线吸收和核电离谱。我们发现X射线探针光谱的振动曲线对IR和X射线脉冲的极化具有敏感性。对于X射线吸收和X射线光电子光谱，这种偏振依赖性在质量上是不同的。该极化相关性的测量值允许从电子基态的最低振动水平和抽运振动水平中选择Franck-Condon分布的差异。所提出的技术使用泵浦的CO分子的X射线吸收光谱进行了数值示例。我们还表明，这种泵浦探针光谱可以使分子旋转动力学的研究成为可能。