一种基于Ca线线指数回归的恒星大气金属丰度估计方法

A Method to Estimate Metal Abundance from Stellar Spectra Using Ca Line Index

提出一种基于BP神经网络及Ca线线指数估计恒星大气金属丰度的方法。该方法以从斯隆数字巡天SDSS中恒星光谱以及SSPP给出的参数作为训练样本,其中每条恒星光谱计算16个Ca线线指数,结合其他方法得到的表面有效温度Teff作为输入,以SSPP得到的金属丰度[Fe/H]作为输出,对训练样本进行重采样后通过训练得到一个人工神经网络,通过该网络可以用来预测恒星光谱的[Fe/H]。通过相关实验表明,提出的方法能够准确而且有效的测量出恒星光谱的[Fe/H]。

This paper presents a method to estimate stellar metallicity based on BP neural network and Ca line index.This meth-od trains a BP ANN model from SDSS/SEGUE stellar spectra and parameters provided by SSPP.The values of Teff and the line index of Ca lines are the input of network while the [Fe/H]values are the oputput of the network.A set of samples are resam-pled from the set of all and then a network model Is trained.The network can be used to predict the stellar metallicity from low-resolution spsectra.The experiment shows that the proposed method can accurately and effectively measure the [Fe/H]from the stellar spectra.