论文标题
高红移星系的LYC逃生分数估算的警示性故事
A Cautionary Tale of LyC Escape Fraction Estimates from High Redshift Galaxies
论文作者
论文摘要
测量逃逸分数，$ f _ {\ rm esc} $，电离，莱曼连续体（Lyc）辐射是我们对宇宙恢复过程的理解的关键。在本文中，我们提供了一种方法，用于恢复LYC逃生部分的后验概率分布，$ f _ {\ rm ESC}^{\ rm pdf} $，考虑到观察性的不确定性和模拟传输函数的合并，并通过Intergalactic介质（IGM）。我们介绍了该方法的一个示例，适用于$ z = 3.64 $的Vuds星系，找到$ f _ {\ rm Esc}^{\ rm pdf} $ = 0.51 $ = 0.51 $^{+0.33} _ { - 0.34} $，并与之相比，并不考虑到均值的镜头，并且相比之下。美元我们的结果突出显示了假设平均光滑传输功能的方法的局限性。我们还提供了基于$ z> 3.4 $的光度红移选择的七个LYC候选者的样本的Mosfire数据，但发现所有七个均已高估了$ΔZ\ sim 0.2 $的高估光度红移0.2 $，这使得它们不适合LYC测量。这可能是由于我们的选择标准引起的偏见。
Measuring the escape fraction, $f_{\rm esc}$, of ionizing, Lyman Continuum (LyC) radiation is key to our understanding of the process of cosmic reionization. In this paper we provide a methodology for recovering the posterior probability distribution of the LyC escape fraction, $f_{\rm esc}^{\rm PDF}$, considering both the observational uncertainties and ensembles of simulated transmission functions through the intergalactic medium (IGM). We present an example of this method applied to a VUDS galaxy at $z=3.64$ and find $f_{\rm esc}^{\rm PDF}$ = 0.51$^{+0.33}_{-0.34}$ and compare this to the values computed assuming averaged IGM transmission with and without consideration of detection bias along average sightlines yielding $f_{\rm esc}^{\langle T \rangle}$ = 1.40$^{+0.80}_{-0.42}$, and $f_{\rm esc}^{\rm bias}$ = 0.82$^{+0.33}_{-0.16}$. Our results highlight the limitations of methods assuming average, smooth transmission functions. We also present MOSFIRE data for a sample of seven LyC candidates selected based on photometric redshifts at $z > 3.4$, but find that all seven have overestimated photometric redshifts by $Δz \sim 0.2$ making them unsuitable for LyC measurements. This results likely due to a bias induced by our selection criteria.
