Stellar population synthesis is an important method in the galaxy and star-cluster studies. In the stellar population synthesis models, stellar spectral library is necessary for the integrated spectra of the stellar population. Usually, the stellar spectral library is used to the transformation between the stellar atmospheric parameters and the stellar spectrum. The empirical stellar spectral library has irreplaceable advantages than the theoretical library. However, for the empirical spectral library, the distribution of stars is irregularly in the stellar atmospheric parameter space, this makes the traditional interpolator difficult to get the accurate results. In this work, we will provide an improved radial basis function interpolator which is used to obtain the interpolated stellar spectra based on the empirical stellar spectral library. For this interpolator, we use the relation between the standard variance {\sigma} in the Gaussian radial basis function and the density distribution of stars in the stellar atmospheric parameter space to give the prior constraint on this {\sigma}. Moreover, we also consider the anisotropic radius basis function by the advantage of the local dispersion of stars in the stellar atmospheric parameter space. Furthermore, we use the empirical stellar spectral library MILES to test this interpolator. On the whole, the interpolator has a good performance except for the edge of the low-temperature region. At last, we compare this interpolator with the work in Cheng et al. (2018), the interpolation result shows an obvious improvement. Users can use this interpolator to get the interpolated spectra based on the stellar spectral library quickly and easily.

中文翻译：

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基于经验恒星光谱库的光谱计算径向基函数网络的升级插值器

星族合成是星系和星团研究的重要方法。在星族合成模型中，星族谱库是综合星族谱的必要条件。通常，恒星光谱库用于恒星大气参数与恒星光谱的转换。经验恒星光谱库比理论库具有不可替代的优势。然而，对于经验谱库，恒星大气参数空间中恒星的分布是不规则的，这使得传统的插值器难以得到准确的结果。在这项工作中，我们将提供一种改进的径向基函数插值器，用于获得基于经验恒星光谱库的插值恒星光谱。对于这个插值器，我们使用高斯径向基函数中的标准方差{\sigma}与恒星大气参数空间中恒星的密度分布之间的关系来给出对这个{\sigma}的先验约束。此外，我们还利用恒星在恒星大气参数空间中局部分散的优势，考虑了各向异性半径基函数。此外，我们使用经验恒星光谱库 MILES 来测试这个内插器。整体来看，除低温区边缘外，插值器性能良好。最后，我们将这个插值器与 Cheng 等人的工作进行了比较。(2018)，插值结果显示出明显的改善。用户可以使用该插值器快速轻松地获得基于恒星光谱库的插值光谱。