We present a comprehensive study of photoionization of OH radicals from the ground and first excited electronic states. Cross sections and asymmetry parameters for the valence orbitals are reported for photon energies from near the threshold to 60 eV. The calculations have been performed with the $R$-matrix method. Two different continuum basis types, namely, the Gaussian and $B$-spline bases, are used to assess the quality of the description of the continuum. The results show both types of continuum bases provide a similar quality description in the near threshold resonant region, but the latter can predict more reliable photoionization observables in higher-energy regions. Our calculations are compared with available experimental and theoretical results, and the discussions are provided.

中文翻译：

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OH自由基的基态和第一激发态的光电离截面

我们对来自地面和第一激发电子态的 OH 自由基的光电离进行了全面的研究。报告了从阈值附近到 60 eV 的光子能量的价轨道的横截面和不对称参数。计算是用$\mathrm{电阻}$-矩阵方法。两种不同的连续基类型，即高斯和$乙$-样条基，用于评估连续统描述的质量。结果表明，两种类型的连续基在近阈值共振区域提供了相似的质量描述，但后者可以预测更高能量区域中更可靠的光电离观测值。我们的计算与可用的实验和理论结果进行了比较，并提供了讨论。