A Tale of Two Herbig Ae Stars, MWC 275 and AB Aurigae: Comprehensive Models for Spectral Energy Distribution and Interferometry
A Tale of Two Herbig Ae Stars, MWC 275 and AB Aurigae: Comprehensive Models for Spectral Energy Distribution and Interferometry
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两颗 Herbig Ae 星 MWC 275 和 AB Aurigae 的故事：光谱能量分布和干涉测量的综合模型
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发表时间：
2008
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通讯作者：
N. Turner
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文献类型：
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作者：
A. Tannirkulam;J. Monnier;T. Harries;R. Millan;Z. Zhu;E. Pedretti;M. Ireland;P. Tuthill;T. Brummelaar;H. Mcalister;C. Farrington;P. J. Goldfinger;J. Sturmann;L. Sturmann;N. Turner
我们提出了全面的赫比格Ae星MWC 275和AB Aur的模型，旨在解释他们的光谱能量分布（从紫外线到毫米）和长基线干涉（从近红外到毫米）的同时。文献中的数据，结合新的中红外（MIR）干涉从凯克段倾斜实验，使用轴对称蒙特卡罗辐射传输代码建模。模型中，大部分的近红外（NIR）发射来自尘埃边缘不适合近红外光谱能量分布（SED）和亚毫角秒近红外CHARA干涉。根据最近的工作，我们包括一个额外的气体排放组件，具有类似的尺寸尺度的尘埃边缘，升华半径内，以适应近红外SED和长基线近红外干涉MWC 275和AB Aur。在没有气体对星光的屏蔽的情况下，我们证明了这些YSO中的气尘过渡区必须包含高度耐火的尘埃，在~1850 K升华。尽管MWC 275和AB Aur在热近红外光谱中具有几乎相同的结构，但它们的外盘却有很大的不同。与AB Aur盘相反，MWC 275在盘的大气中缺乏能够产生超过~7 Au的显著10-20 μm发射的小颗粒，迫使外部区域进入内部盘的“阴影”。
We present comprehensive models for the Herbig Ae stars MWC 275 and AB Aur that aim to explain their spectral energy distribution (from UV to millimeter) and long-baseline interferometry (from near-infrared to millimeter) simultaneously. Data from the literature, combined with new mid-infrared (MIR) interferometry from the Keck Segment Tilting Experiment, are modeled using an axisymmetric Monte Carlo radiative transfer code. Models in which most of the near-infrared (NIR) emission arises from a dust rim fail to fit the NIR spectral energy distribution (SED) and sub-milliarcsecond NIR CHARA interferometry. Following recent work, we include an additional gas emission component with similar size scale to the dust rim, inside the sublimation radius, to fit the NIR SED and long-baseline NIR interferometry on MWC 275 and AB Aur. In the absence of shielding of starlight by gas, we show that the gas-dust transition region in these YSOs will have to contain highly refractory dust, sublimating at ~1850 K. Despite having nearly identical structure in the thermal NIR, the outer disks of MWC 275 and AB Aur differ substantially. In contrast to the AB Aur disk, MWC 275 lacks small grains in the disk atmosphere capable of producing significant 10-20 μm emission beyond ~7 AU, forcing the outer regions into the “shadow” of the inner disk.