AI 中文总结
研究以天蝎座上盘为对象，构建辐射传输模型网格提高尘埃质量估计精度，通过对比得出该区域盘的尘埃质量中值，发现其远低于豺狼座I盘，证实恒星质量与尘埃质量相关性及差异，揭示盘演化中尘埃颗粒的变化情况。
AI 中文摘要
原行星盘的总尘埃质量是决定行星形成潜力的关键属性。年龄约为5 - 12百万年的天蝎座上盘（USco），为研究与行星形成时间尺度相当的尘埃库演化提供了重要平台。在本研究中，我们利用该区域目前最大的ALMA 0.88毫米连续谱样本，分析了USco中136个完整和过渡盘的尘埃质量分布。为提高尘埃质量估计的准确性，构建了918个自洽辐射传输模型网格，考虑了恒星质量相关的盘大小、吸积率和多孔尘埃属性。模型得出了尘埃温度与恒星光度之间的新校准关系，预测低质量恒星的尘埃温度比常用公式更高。使用这些修正后的尘埃温度和多孔尘埃不透明度，我们得出了USco盘的尘埃质量，并与豺狼座I恒星形成区域中较年轻的样本进行比较。我们发现USco盘的尘埃质量中值为0.95M_E，约为豺狼座I盘（5.69M_E）的六分之一，这为盘演化最初几百万年中毫米大小尘埃颗粒的大量消耗提供了有力证据。我们证实了之前恒星质量与尘埃质量之间高度显著的相关性，且USco中的关系比豺狼座I中略陡。USco中观测到的低尘埃质量，以及与成熟系外行星系统的比较表明，很大一部分原始固体库已被纳入更大天体、因径向漂移而移除或在5 - 12百万年时对毫米观测不可见。
英文摘要
The total dust mass of protoplanetary disks is a key property that determines the potential for planet formation. Upper Scorpius (USco), with an age of ~5-12Myr, provides an important laboratory for investigating the evolution of dust reservoirs on timescales comparable to those of planet formation. In this work, we analyze the dust mass distribution of 136 full and transitional disks in USco using the largest ALMA 0.88mm continuum sample currently available for the region. To improve the accuracy of dust mass estimates, we construct a grid of 918 self-consistent radiative transfer models that account for stellar-mass-dependent disk sizes, accretion rates, and porous dust properties. The models yield a new calibration between dust temperature and stellar luminosity, predicting systematically higher dust temperatures for low-mass stars than commonly adopted prescriptions. Using these revised dust temperatures together with porous dust opacities, we derive dust masses for the USco disks and compare them with those of a younger sample in the Chamaeleon~I star-forming region. We find a median dust mass of 0.95M_E for the USco disks, approximately six times lower than that of the Chamaeleon I disks (5.69M_E), providing strong evidence for substantial depletion of millimeter-sized dust grains over the first several Myr of disk evolution. We confirm the previous finding of a highly significant correlation between stellar mass and dust mass, with a slightly steeper relation in USco than in Chamaeleon I. The low dust masses observed in USco, together with their comparison to mature exoplanetary systems, suggest that a large fraction of the primordial solid reservoir has already been incorporated into larger bodies, removed by radial drift, or hidden from millimeter observations by ages of 5-12 Myr.
Comments14 pages, 5 figures, accepted for publication in Research in Astronomy and Astrophysics
