Abstract

Variable circumstellar extinction models as applied to T Tauri stars are considered. In contrast to hotter UX Ori stars, for which simplified eclipse models are applicable, the star is deemed a point source of light, while the circumstellar dust clouds obscuring the star are assumed to be homogeneous. In the case considered here, both these simplifications may not work. Hot accretion spots are formed through accretion on T Tauri stars, while the dust structures obscuring the star from the observer can be inhomogeneous within the stellar disk. The families of color–magnitude diagrams have been computed by taking into account these two factors. It is shown that in such models the color tracks on the diagrams can differ greatly in shape from those computed in eclipse models for hot UX Ori stars. The results obtained may be applicable to AA Tau stars demonstrating eclipses by the inner circumstellar disk regions.

中文翻译：

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可变星际消光模型中T Tauri星的颜色指标

摘要

考虑了应用于T Tauri恒星的可变星际灭绝模型。相对于较热的UX Ori恒星，适用简化的月食模型，该恒星被认为是点光源，而假定遮盖恒星的星云尘埃云是均匀的。在这里考虑的情况下，这两种简化可能都不起作用。在T Tauri恒星上通过吸积形成热吸积点，而从观测者遮挡恒星的尘埃结构在恒星盘内可能是不均匀的。通过考虑这两个因素，可以计算出色阶图的族。结果表明，在这样的模型中，图中的颜色轨迹的形状可能与针对UX Ori恒星的日食模型中计算出的颜色轨迹大不相同。