论文标题
使用高斯工艺自动测量类星体红移
Automated Measurement of Quasar Redshift with a Gaussian Process
论文作者
论文摘要
我们开发了一种自动化技术，可以在斯隆数字天空调查（SDSS）的巴属振荡光谱调查（BOSS）中测量类星体红移。我们的技术是一种早期的高斯工艺方法的扩展，该方法用于检测具有已知红移的类星体光谱中的lyman-Alpha吸收剂（DLAS）。我们将此技术应用于SDSS DR12的子样本，而BAL类星体已删除和大于2.15的红移。我们表明，我们与现有的类星红移估计器具有广泛的竞争力，在仅0.38％的光谱中，PCA红移不同意0.5。我们的方法为类星体红移产生了概率密度函数，从而使类星体红移不确定性传播到下游用户。我们将此方法应用于检测DLA，以贝叶斯方式进行红移不确定性进行核算。与我们先前具有已知类星性红移的方法相比，我们检测到DLA的能力中等，主要是在最噪声中。曲线下的面积从0.96下降到0.91。我们的代码公开可用。
We develop an automated technique to measure quasar redshifts in the Baryon Oscillation Spectroscopic Survey (BOSS) of the Sloan Digital Sky Survey (SDSS). Our technique is an extension of an earlier Gaussian process method for detecting damped Lyman-alpha absorbers (DLAs) in quasar spectra with known redshifts. We apply this technique to a subsample of SDSS DR12 with BAL quasars removed and redshift larger than 2.15. We show that we are broadly competitive to existing quasar redshift estimators, disagreeing with the PCA redshift by more than 0.5 in only 0.38% of spectra. Our method produces a probabilistic density function for the quasar redshift, allowing quasar redshift uncertainty to be propagated to downstream users. We apply this method to detecting DLAs, accounting in a Bayesian fashion for redshift uncertainty. Compared to our earlier method with a known quasar redshift, we have a moderate decrease in our ability to detect DLAs, predominantly in the noisiest spectra. The area under curve drops from 0.96 to 0.91. Our code is publicly available.
