论文标题
解释具有湍流介质的环境培养基中吸收线的观察
Interpreting Observations of Absorption Lines in the Circumgalactic Medium with a Turbulent Medium
论文作者
论文摘要
单相光电离平衡（PIE）模型通常用于推断出在不同电离势下吸收离子时探测的星系卤素的潜在物理特性。为了结合湍流的影响，我们使用Maihem代码对暴露于红移零的元乳酸紫外线背景的各向同性湍流介质进行建模，同时跟踪电离，重组和物种的辐射辐射冷却，以使其散发出多种离子。通过比较马尔可夫链蒙特卡洛技术的广泛湍流速度，密度和金属性的观察和模拟，我们发现Maihem模型提供了与观察到的低离子化物种相比相比与PIE模型相比的低离子化物种同样适合的，而在同一时间上以\ ion等高离子化为\ ion，例如\ ion {si} {siion} {4 iion} {4 iiN} {通过包含多个阶段，与PIE型号相比，Cargalactic培养基具有更高的金属度（$ z/z_ \ odot \约40 \％$）。此外，所有解决方案都需要一定数量的湍流（$σ_ {\ rm 3d} \ geqslant 26 \ {\ rm km} \ {\ rm {\ rm s}^{ - 1} $）。湍流，金属性，柱密度和影响参数之间的相关性与驱动光环内湍流的机制讨论。
Single-phase photoionization equilibrium (PIE) models are often used to infer the underlying physical properties of galaxy halos probed in absorption with ions at different ionization potentials. To incorporate the effects of turbulence, we use the MAIHEM code to model an isotropic turbulent medium exposed to a redshift zero metagalactic UV background, while tracking the ionizations, recombinations, and species-by-species radiative cooling for a wide range of ions. By comparing observations and simulations over a wide range of turbulent velocities, densities, and metallicity with a Markov chain Monte Carlo technique, we find that MAIHEM models provide an equally good fit to the observed low-ionization species compared to PIE models, while reproducing at the same time high-ionization species such as \ion{Si}{4} and \ion{O}{6}. By including multiple phases, MAIHEM models favor a higher metallicity ($Z/Z_\odot \approx 40\%$) for the circumgalactic medium compared to PIE models. Furthermore, all of the solutions require some amount of turbulence ($σ_{\rm 3D} \geqslant 26\ {\rm km}\ {\rm s}^{-1}$). Correlations between turbulence, metallicity, column density, and impact parameter are discussed alongside mechanisms that drive turbulence within the halo.
