发表机构
University of Exeter; University of Michigan; Texas State University（埃克塞特大学; 密歇根大学; 德克萨斯州立大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究利用新二维模型MAGPIE，量化了扩散、平流及卵石漂移等动力学过程对原行星盘水丰度和红外光谱的影响，发现输运可补充水层并改变谱线特征，但卵石漂移对冷水示踪物影响有限。
AI 中文摘要
原行星盘的红外水光谱（例如由JWST观测到的）编码了关于底层水分布和物理条件的信息。在这项工作中，我们使用一个名为“分子发射受气体、卵石和冰演化影响”（MAGPIE）的新二维模型，检验并量化各种动力学过程（单独或联合作用）对水丰度和涌现光谱的影响。该模型结合了水（及相关物种）和尘埃颗粒的扩散与平流，以及空气动力学解耦的卵石，并包含光解离和气相水形成方案。总体而言，我们发现输运过程对内盘的水含量有重大影响，并且可以（重新）补充冰储层上方的层，而在静态模型中，该层由于光解离而水贫乏。特别是，将扩散添加到化学模型中可能导致光谱的强烈变化（例如，较冷水线相比较热水线的通量增加），最近的工作已将此与卵石漂移联系起来。添加卵石漂移显著增加了内盘的水丰度，但令人惊讶的是，并未轻易导致冷水示踪物的进一步增加，因为（1）水蒸气的高效向外输运受到进入卵石的传送带效应的抑制，以及（2）热水线通量的增加掩盖了较冷线的较小增加。我们得出结论，动力学过程对水光谱具有显著但复杂的影响。未来的工作应探索一系列恒星（例如紫外线照射）和盘的性质，以全面理解观测到的水发射多样性。
英文摘要
Protoplanetary discs' infrared water spectra (e.g. as observed by JWST) encode information about the underlying water distribution and physical conditions. In this work, we examine and quantify the imprint of various dynamical processes (operating alone or in unison) on water abundances and emerging spectra using a new 2D model called Molecular emission Affected by Gas, Pebble, and Ice Evolution (MAGPIE). This model combines diffusion and advection for water (and associated species) and dust grains with aerodynamically decoupled pebbles, and photodissociation and a gas-phase water formation prescription. In general, we find that transport processes have a major impact on the inner disc's water content and can (re)plenish the layer above the ice reservoir which in static models is water-poor due to photodissociation. In particular, adding diffusion to a chemical model can result in strong changes in the spectrum (e.g. a flux increases of colder compared to warmer water lines) that recent work has associated with pebble drift. Adding pebble drift dramatically increases the inner disc water abundance but, surprisingly, does not readily lead to a further increase of cold water tracers as (1) efficient outward transport of water vapour is inhibited by a conveyor belt effect of incoming pebbles, and (2) the increase in hot water line fluxes overshadows smaller increases of colder lines. We conclude that dynamical processes have a significant but complex impact on water spectra. Future work should explore a range in stellar (e.g. UV irradiation) and disc properties to comprehensively understand the observed diversity of water emission.
Comments25 pages, 23 figures; accepted for publication in MNRAS
