论文标题
银河光谱分析中播层培养基的有效不透明度
Effective Opacity of the Intergalactic Medium from Galaxy Spectra Analysis
论文作者
论文摘要
我们从281个Lyman-Break Galaxies（LBGS）的复合光谱（$τ_{eff} $）的有效不透明度（$τ_{eff} $）中测量Redshift范围中的281个Lyman-Break Galaxies（LBG）的有效不透明度（IGM）。我们的光谱取自W.M.上低分辨率成像光谱仪（LRIS）得出的Cosmos Lyman-Alpha映射和层析成像观测值（Clamato）调查。凯克我望远镜。我们以两个红移间隔生成复合光谱，并使用由简单恒星种群组成的光谱能量分布（SED）模型。将这些SED型号推送到Ly $α$ Forest中，我们在$ 2.02 \ leq Z \ LEQ 2.44 $范围内测量有效的$ ly $α$不透明度（$τ_{eff} $）。在$ z = 2.22 $，我们估计$τ_{eff} = 0.159 \ pm 0.001 $从powerlaw Fit到数据。这些测量值与$ z <2.5 $的类星体分析中的估计值一致，表明与标准类的continua相关的系统错误并不是很大的。我们提供了我们结果的高斯流程模型以及以前的$τ_{eff} $测量值，该测量描述了$ z = 1.5-4 $的$τ_{eff} $中陡峭的红移演变。
We measure the effective opacity ($τ_{eff}$) of the Intergalactic Medium (IGM) from the composite spectra of 281 Lyman-Break Galaxies (LBGs) in the redshift range $2 \lesssim z \lesssim 3$. Our spectra are taken from the COSMOS Lyman-Alpha Mapping And Tomographic Observations (CLAMATO) survey derived from the Low Resolution Imaging Spectrometer (LRIS) on the W.M. Keck I telescope. We generate composite spectra in two redshift intervals and fit them with spectral energy distribution (SED) models composed of simple stellar populations. Extrapolating these SED models into the Ly$α$ forest, we measure the effective Ly$α$ opacity ($τ_{eff}$) in the $2.02 \leq z \leq 2.44$ range. At $z = 2.22$, we estimate $τ_{eff} = 0.159 \pm 0.001$ from a power-law fit to the data. These measurements are consistent with estimates from quasar analyses at $z<2.5$ indicating that the systematic errors associated with normalizing quasar continua are not substantial. We provide a Gaussian Processes model of our results and previous $τ_{eff}$ measurements that describes the steep redshift evolution in $τ_{eff}$ from $z = 1.5 - 4$.
