Cavities in inner disks : the GM Aurigae case
Cavities in inner disks : the GM Aurigae case
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内盘中的空洞：GM Aurigae 案例
DOI：
10.1051/0004-6361:200810732
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发表时间：
2008
影响因子：
6.5
通讯作者：
D. Semenov
中科院分区：
文献类型：
--
作者：
A. Dutrey;S. Guilloteau;V. Piétu;E. Chapillon;F. Gueth;T. Henning;R. Launhardt;Y. Pavlyuchenkov;K. Schreyer;D. Semenov
上下文最近的建模的基础上未解决的红外观测光谱能量分布（SED）的御夫座GM建议，这一单一的金牛座星星的内盘被截断的内半径为25 Au。目标。我们试图找到这个内孔的气体分布的证据，使用光谱与高角分辨率。方法.利用IRAM阵列，我们获得了13条CO $J=2{-}1$和C18 O $J= 2 {-} 1 $以及13条CO $J=1{-}0$线的高角分辨率（~1.5”）和高信噪比的单道观测结果。 一个标准的参数磁盘模型被用来拟合傅立叶平面中的线数据，并推导出CO磁盘属性。我们的测量是基于对以开普勒速度旋转的CO盘的光谱轮廓的详细分析。毫米连续谱，跟踪灰尘，也进行了分析。结果我们在4.5 σ水平上探测到一个半径为19 ± 4 Au的内腔。黑洞的表现是在内部半径处没有超过开普勒速度（投影）的发射。我们还限制了圆盘中的温度梯度。结论.我们的数据揭示了在GM Aur气盘中存在一个内孔。它的起源仍不清楚，但可能与行星的形成有关，或与靠近中心星星（约5-15 Au）的低质量恒星伴星有关。频繁发现的内部空腔表明，要么双星是金牛座星星形成的最常见的场景，要么巨行星的形成很早就开始了。
Context. Recent modeling based on unresolved infrared observations of the spectral energy distribution (SED) of GM Aurigae suggests that the inner disk of this single TTauri star is truncated at an inner radius of 25 AU. Aims. We attempt to find evidence of this inner hole in the gas distribution, using spectroscopy with high angular resolution. Methods. Using the IRAM array, we obtained high angular resolution (~1.5”) observations with a high S/N per channel of the 13 CO $J=2{-}1$ and C 18 O $J=2{-}1$ and of the 13 CO $J=1{-}0$ lines. A standard parametric disk model is used to fit the line data in the Fourier-plane and to derive the CO disk properties. Our measurement is based on a detailed analysis of the spectroscopic profile from the CO disk rotating in Keplerian velocity. The millimeter continuum, tracing the dust, is also analyzed. Results. We detect an inner cavity of radius 19 ± 4 AU at the 4.5 σ level. The hole manifests itself by a lack of emission beyond the (projected) Keplerian speed at the inner radius. We also constrain the temperature gradient in the disk. Conclusions. Our data reveal the existence of an inner hole in GM Aur gas disk. Its origin remains unclear, but can be linked to planet formation or to a low mass stellar companion orbiting close to the central star (~5-15 AU). The frequent finding of inner cavities suggests that either binarity is the most common scenario of star formation in Taurus or that giant planet formation starts early.