We study the hydrostatic density structure of the inner disc rim around HerbigAe stars using the thermo-chemical hydrostatic code ProDiMo. We compare the Spectral Energy Distributions (SEDs) and images from our hydrostatic disc models to that from prescribed density structure discs. The 2D continuum radiative transfer in ProDiMo includes isotropic scattering. The dust temperature is set by the condition of radiative equilibrium. In the thermal-decoupled case the gas temperature is governed by the balance between various heating and cooling processes. The gas and dust interact thermally via photoelectrons, radiatively, and via gas accommodation on grain surfaces. As a result, the gas is much hotter than in the thermo-coupled case, where the gas and dust temperatures are equal, reaching a few thousands K in the upper disc layers and making the inner rim higher. A physically motivated density drop at the inner radius ("soft-edge") results in rounded inner rims, which appear ring-like in near-infrared images. The combination of lower gravity pull and hot gas beyond ~1 AU results in a disc atmosphere that reaches a height over radius ratio z/r of 0.1 while this ratio is 0.2 only in the thermo-coupled case. This puffed-up disc atmosphere intercepts larger amount of stellar radiation, which translates into enhanced continuum emission in the 3- 30 micron wavelength region from hotter grains at ~500 K. We also consider the effect of disc mass and grain size distribution on the SEDs self-consistently feeding those quantities back into the gas temperature, chemistry, and hydrostatic equilibrium computation.
A family portrait of disk inner rims around Herbig Ae/Be stars: Hunting for warps, rings, self shadowing, and misalignments in the inner astronomical units
Ammonium salt formation and abundance in protoplanetary disks
Université Bordeaux, CNRS, Bordeaux INP, ISM, UMR 5255（波尔多大学）；Carl Sagan Center, SETI Institute（卡尔·萨根中心，SETI研究所）；NASA Ames Research Center（NASA艾姆斯研究中心）
Gas chemistry in the dust depleted inner regions of protoplanetary disks. I. Near-IR spectra and overtones
Max-Planck Institute for extraterrestrial physics（马克斯·普朗克地外物理研究所）；Kapteyn Astonomical Institute, University of Groningen（格罗宁根大学卡普坦天文研究所）；University Observatory, Faculty of Physics, Ludwig-Maximilians-University at Munchen（慕尼黑路德维希-马克西米利安大学物理学院天文台）；Max-Planck-Institut fur Astronomie（马克斯·普朗克天文学研究所）
Constraining the radial drift of millimeter-sized grains in the protoplanetary disks in Lupus
最近ALMA对原行星盘的调查表明，对于大多数盘，气体排放的程度大于毫米级尘埃的热排放程度。线光学深度和径向依赖的晶粒生长和径向漂移的组合效应可能有助于这种观察到的效果。对于一个样本的10个磁盘从狼疮调查，我们调查如何以及尘埃为基础的模型没有径向尘埃演变再现所观察到的12CO外半径，并确定是否需要径向尘埃演变，以匹配所观察到的气体尘埃尺寸差异。我们使用的热化学代码DALI获得12 CO合成排放图和测量气体和尘埃的外半径（Rco，Rmm）使用相同的方法适用于观测，这是比较的观测源的基础上。对于5个圆盘，我们发现观测到的气尘尺寸差大于由光学厚度引起的气尘尺寸差，这表明我们需要尘埃演化和光学厚度效应来解释观测到的气尘尺寸差。对于其他5个磁盘所观察到的气体尘埃的尺寸差异可以解释只有线光学深度效应。我们还确定了6个磁盘不包括在我们的初始样本，但同一恒星形成区域的调查的一部分，显示显着的12CO排放超过4 x Rmm。这些磁盘，没有Rco是可用的，可能有气体尘埃的大小差异大于4，很难解释没有实质性的尘埃演变。我们的研究结果表明，径向漂移和晶粒生长是共同的特点，明亮和暗淡的磁盘。在尘埃和气体半径显著不同的圆盘中可以观察到径向漂移和晶粒生长的影响，而在差异较小的圆盘中需要更详细的模型和更深入的观察才能看到这种影响。
HD far infrared emission as a measure of protoplanetary disk mass
年轻恒星周围的原行星盘是行星形成的场所。虽然尘埃质量可以用标准方法估算，但确定气体质量-从而确定可形成巨行星的材料数量-已被证明非常困难。氘化氢（HD）是一个很有前途的替代常用的气体质量示踪剂，CO。我们的目标是检查HD的磁盘气体质量的示踪剂的鲁棒性，特别是气体质量对HD FIR发射的影响及其对垂直结构的敏感性。在热化学代码DALI中实现了与HD相关的氘化学反应，并针对一系列磁盘质量和垂直结构运行了模型。HD J=1-0线强度直接取决于气体质量通过一个次线性幂律关系与斜率为~0.8。假设没有关于盘的垂直结构的先验知识，并且仅使用HD 1-0通量，对于低质量盘（M $_{\rm disk} < 10^{-3}$ M $_\odot$），气体质量可以被估计为在2的因子内。对于更大质量的磁盘，这种不确定性增加到超过一个数量级。增加HD 2-1谱线或关于垂直结构的独立信息可以将这种不确定性降低到所有磁盘质量的约3倍。对于TW Hya，使用Kama等人2016 b的径向和垂直结构，观测结果将气体质量限制为$6\cdot10^{-3}$ M $_\odot$ < M $_{\rm disk} < 9\cdot10^{-3}$ M $_\odot$。未来的观测要求$σ$的灵敏度为$1.8\cdot10^{-20}$ W m $^{-2}$（$2.5\cdot10^{-20}$ W m $^{-2…
Tree-based solvers for adaptive mesh refinement code FLASH -- IV: An X-ray radiation scheme to couple discrete and diffuse X-ray emission sources to the thermochemistry of the interstellar medium
