论文标题
TDCOSMO III：暗物质子结构符合暗能量 - （子）光环对$ H_0 $的强镜测量的影响
TDCOSMO III: Dark matter substructure meets dark energy -- the effects of (sub)halos on strong-lensing measurements of $H_0$
论文作者
论文摘要
时间延迟宇宙学使用强度重力镜片中图像之间的到达时间延迟来测量宇宙参数，尤其是哈勃常数$ h_0 $。在时间延迟宇宙学上使用的镜头模型省略了暗物质Subhalos和视线光环，因为假定它们的效果可以忽略不计。我们通过分析包括暗物质Subhalos和视线光晕的模拟透镜系统来明确量化这一假设，并应用文献中使用的相同的建模假设来推断$ H_0 $。我们将模拟透镜基于六个四倍成像的类星体，这些类星体对哈勃常数进行了测量，并按照镜头的基础量化了其他不确定性和/或偏差。我们表明，省略深色子结构不会偏向$ H_0 $的推断。但是，子结构的扰动在$ h_0 $的推断值中贡献了一个随机不确定性的附加来源，该$ h_0 $缩放为镜头量的平方根除以最长的时间延迟。我们提供拟合功能的这种附加不确定性来源范围为$ 0.7-2.4 \％$。它可能需要将其纳入错误预算中，因为单镜头的精确推论的精度有所改善，并确定了单镜头推断的精确限制。
Time delay cosmography uses the arrival time delays between images in strong gravitational lenses to measure cosmological parameters, in particular the Hubble constant $H_0$. The lens models used in time delay cosmography omit dark matter subhalos and line-of-sight halos because their effects are assumed to be negligible. We explicitly quantify this assumption by analyzing mock lens systems that include full populations of dark matter subhalos and line-of-sight halos, applying the same modeling assumptions used in the literature to infer $H_0$. We base the mock lenses on six quadruply-imaged quasars that have delivered measurements of the Hubble constant, and quantify the additional uncertainties and/or bias on a lens-by-lens basis. We show that omitting dark substructure does not bias inferences of $H_0$. However, perturbations from substructure contribute an additional source of random uncertainty in the inferred value of $H_0$ that scales as the square root of the lensing volume divided by the longest time delay. This additional source of uncertainty, for which we provide a fitting function, ranges from $0.7 - 2.4\%$. It may need to be incorporated in the error budget as the precision of cosmographic inferences from single lenses improves, and sets a precision limit on inferences from single lenses.
