Tidal stripping and disk kinematics in the RW Aurigae system
Tidal stripping and disk kinematics in the RW Aurigae system
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RW Aurigae 系统中的潮汐剥离和圆盘运动学
DOI：
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发表时间：
2006
期刊：
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通讯作者：
C. Dougados
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作者：
S. Cabrit;J. Pety;N. Pesenti;C. Dougados
我们展示了用 IRAM Plateau de Bure 干涉仪在 CO(2-1)、CO(1-0) 和附近连续谱中获得的 RW~Aur 系统的干涉图。亚弧秒角分辨率 (0.89'' x 0.58'') 和在 1.3mm 处达到的高灵敏度使我们能够解析三种分子结构：(1) 围绕 RWAur A 绕光学射流轴旋转的光学厚盘，(2) RWAur B 周围受干扰的不对称峰，(3) 从 RWAur A 盘拖尾的 600 个天文单位长的材料“臂”。与开普勒模型的比较表明，RWAur A盘是迄今为止在金牛座T星（半径40-57 AU）周围检测到的最小的盘，并且外缘的CO排放层比尘埃更温暖（T〜60-100 K）并且相对较厚（Nwarm〜0.1-10 x 1e22 cm-2）。所检测到的特征的形态和运动学强烈表明，我们正在目睹 RWAur B 最近飞过的主盘的潮汐剥离。我们推测，潮汐耗散可能解释了与典型的金牛座 T 星相比，RWAur A 盘中气体温度更高的原因，并且可能在其吸积率升高中发挥了作用。我们还发现 RWAur A 盘的旋转方向与 Woitas 等人报道的光学射流中的横向速度变化相反。 （2005）。我们认为这些横向位移可能仅代表真实射流旋转速度的上限。这些限制与从磁盘启动的 MHD 的当前型号保持一致。
We present interferometric maps of the RW~Aur system obtained with the IRAM Plateau de Bure Interferometer in CO(2-1), CO(1-0), and nearby continuum. The sub-arcsecond angular resolution (0.89'' x 0.58'') and high-sensitivity reached at 1.3mm enable us to resolve three molecular structures: (1) an optically thick disk around RWAur A in rotation about the optical jet axis, (2) a disturbed asymmetric peak around RWAur B, (3) a 600 AU-long ``arm'' of material trailing from the RWAur A disk. Comparison with Keplerian models indicate that the RWAur A disk is the smallest detected so far around a T Tauri star (radius 40-57 AU) and that the CO emitting layer at the outer edge is warmer than the dust (T ~ 60-100 K) and relatively thick (Nwarm ~ 0.1-10 x 1e22 cm-2). The morphology and kinematics of the detected features strongly suggest that we are witnessing tidal stripping of the primary disk by the recent fly-by of RWAur B. We speculate that tidal dissipation might explain the warmer gas temperatures in the RWAur A disk compared with typical T Tauri stars, and perhaps play a role in its elevated accretion rate. We also find that the rotation sense of the RWAur A disk is opposite to transverse velocity shifts in the optical jet reported by Woitas et al. (2005). We argue that these transverse shifts are likely to represent only upper limits to the true jet rotation speed. The limits remain consistent with current models of MHD launching from the disk.