First Detection of Submillimeter Polarization from T Tauri Stars
First Detection of Submillimeter Polarization from T Tauri Stars
复制标题
首次探测到金牛座 T 星的亚毫米偏振
DOI：
--
复制
发表时间：
1999
期刊：
影响因子：
--
通讯作者：
M. Momose
中科院分区：
文献类型：
--
作者：
M. Tamura;J. Hough;J. Greaves;J. Morino;A. Chrysostomou;W. Holland;M. Momose
本文报道了首次对金牛座T星GM Aur和DG Tau的850 μm连续辐射偏振的观测。这些都是单一的和经典的TTS。辐射主要来自致密的（r < 100 Au）吸积盘。偏振（在~3%的水平，在3 σ）解释的热辐射的磁盘中的磁性排列的尘埃颗粒。因此，这些亚毫米极化探测磁盘中的磁场结构，而以前报道的毫米/亚毫米极化的原恒星和过渡对象从原恒星到TTTS跟踪磁场在较大的包络区。在这两个TTS中，从我们的亚毫米极化推断出的磁场方向平行于通过干涉观测测量的致密尘埃盘的平面，这表明盘中的环形磁场分量占主导地位。讨论了星周环境的磁演化，以及对年轻恒星喷流和外流的MHD模型的限制。
We report a first detection of polarization of the 850 μm continuum emission from two T Tauri stars (TTSs), GM Aur and DG Tau. These are both single and classical TTSs. The emission mostly comes from the compact (r < 100 AU) accretion disks. The polarization (at ~3% level at 3 σ) is interpreted in terms of thermal emission by magnetically aligned dust grains in the disk. Thus these submillimeter polarizations probe the magnetic field structure in the disk, while the previously reported millimeter/submillimeter polarizations of protostars and the transitional objects from the protostars to TTSs trace the magnetic fields in the larger envelope region. In both TTSs, the direction of the magnetic field inferred from our submillimeter polarizations is parallel to the plane of the compact dust disk measured by interferometric observations, suggesting the dominance of a toroidal magnetic field component in the disk. The magnetic evolution of the circumstellar environments is discussed, as well as the constraints on the MHD models of the jets and outflows from young stellar objects.