The Ionized Warped Disk and Disk Wind of the Massive Protostar Monoceros R2-IRS2 Seen with ALMA
The Ionized Warped Disk and Disk Wind of the Massive Protostar Monoceros R2-IRS2 Seen with ALMA
复制标题
用 ALMA 观测到的巨型原恒星麒麟座 R2-IRS2 的电离扭曲盘和盘风
DOI：
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发表时间：
2020
影响因子：
4.9
通讯作者：
V. Rivilla
中科院分区：
文献类型：
--
作者：
I. Jímenez;A. Baez;J. Martín;Qizhou Zhang;V. Rivilla
大质量星星形成理论预测，大质量原恒星通过星周盘吸积气体。虽然由于高角分辨率干涉测量已经发现了几个案例，但这些盘的内部物理结构仍然未知，特别是它们是否存在翘曲或内部孔，就像在低质量原行星盘中观察到的那样。在这里，我们报告了用阿塔卡马大型毫米/亚毫米阵列（光束为80 mas × 60 mas，或70 Au × 50 Au）对麒麟座R2恒星形成星团中的IRS 2大质量年轻恒星天体在第9波段进行的H21α射电复合线的高角分辨率观测。H21α谱线显示了脉泽放大效应，这使我们能够研究大质量原恒星周围电离气体的运动学和物理结构，其空间尺度可达Au 1-2。我们的阿尔马图像和三维辐射传输模型显示，IRS 2周围的电离气体分布在开普勒环星盘和膨胀风。H21α的发射中心在速度介于−10和20 km s−1之间时偏离盘平面，表明盘发生了翘曲。这可以用系统中存在的次要物体（恒星伴星或大质量行星）来解释。电离风似乎是从距中心星星约11 Au的盘表面发射的，与磁调节盘风模型一致。这表明了一个类似的风发射机制，最近发现的演化大质量恒星，如MWC 349 A和MWC 922。
Theories of massive star formation predict that massive protostars accrete gas through circumstellar disks. Although several cases have been found already thanks to high angular-resolution interferometry, the internal physical structure of these disks remains unknown, in particular whether they present warps or internal holes, as observed in low-mass protoplanetary disks. Here, we report very high angular-resolution observations of the H21α radio recombination line carried out in Band 9 with the Atacama Large Millimeter/submillimeter Array (beam of 80 mas × 60 mas, or 70 au × 50 au) toward the IRS2 massive young stellar object in the Monoceros R2 star-forming cluster. The H21α line shows maser amplification, which allows us to study the kinematics and physical structure of the ionized gas around the massive protostar down to spatial scales of ∼1–2 au. Our ALMA images and 3D radiative transfer modeling reveal that the ionized gas around IRS2 is distributed in a Keplerian circumstellar disk and an expanding wind. The H21α emission centroids at velocities between −10 and 20 km s−1 deviate from the disk plane, suggesting a warping for the disk. This could be explained by the presence of a secondary object (a stellar companion or a massive planet) within the system. The ionized wind seems to be launched from the disk surface at distances ∼11 au from the central star, consistent with magnetically-regulated disk wind models. This suggests a similar wind-launching mechanism to that recently found for evolved massive stars such as MWC349A and MWC922.
揭晓 CEPHEUS A HW2 区域的主要热源
DOI：
10.1088/0004-637x/703/2/l157
发表时间：
2009
期刊：
The Astrophysical Journal
影响因子：
--
作者：
Jiménez-Serra I
通讯作者：
Jiménez-Serra I