论文标题
搜索与Calypso的0级原始恒星周围开普勒磁盘的运动学证据
Searching for kinematic evidence of Keplerian disks around Class 0 protostars with CALYPSO
论文作者
论文摘要
原星盘的形成尚不清楚。要了解这些磁盘的形成方式以及何时形成，至关重要的是，以高角度分辨率来表征最年轻的原恒星的运动学。在这里，我们研究了16类原恒星的样本，以测量其从50到500 au的尺度上的旋转曲线，并搜索开普勒旋转。我们使用了使用高原bure干涉仪获得的高角度分辨率线观测作为Calypso大型程序的一部分。 From $\mathrm{^{13}CO}$ ($J=2-1$), $\mathrm{C^{18}O}$ ($J=2-1$) and SO ($N_{j}=5_{6}-4_{5}$) moment maps, we find that seven sources show rotation about the jet axis at a few hundred au scales: SerpS-MM18, L1448-C，L1448-NB，L1527，NGC1333- IRAS2A，NGC1333-IRAS4B和SVS13-B。我们在$ UV $平面中分析了这些来源的运动学，以将旋转曲线得出至50〜AU量表。我们发现仅在两个来源的L1527和L1448-C中旋转开普勒旋转的证据。总体而言，这表明大于50个AU的开普勒磁盘周围很少见。但是，在某些来源中，线发射可能是光学厚的，并由信封发射占主导地位。由于这些信封的光学厚度，在我们的观察结果中，某些磁盘可能仍未被发现。
The formation of protoplanetary disks is not well understood. To understand how and when these disks are formed, it is crucial to characterize the kinematics of the youngest protostars at a high angular resolution. Here we study a sample of 16 Class 0 protostars to measure their rotation profile at scales from 50 to 500~au and search for Keplerian rotation. We used high-angular-resolution line observations obtained with the Plateau de Bure Interferometer as part of the CALYPSO large program. From $\mathrm{^{13}CO}$ ($J=2-1$), $\mathrm{C^{18}O}$ ($J=2-1$) and SO ($N_{j}=5_{6}-4_{5}$) moment maps, we find that seven sources show rotation about the jet axis at a few hundred au scales: SerpS-MM18, L1448-C, L1448-NB, L1527, NGC1333- IRAS2A, NGC1333-IRAS4B, and SVS13-B. We analyzed the kinematics of these sources in the $uv$ plane to derive the rotation profiles down to 50~au scales. We find evidence for Keplerian rotation in only two sources, L1527 and L1448-C. Overall, this suggests that Keplerian disks larger than 50 au are uncommon around Class 0 protostars. However, in some of the sources, the line emission could be optically thick and dominated by the envelope emission. Due to the optical thickness of these envelopes, some of the disks could have remained undetected in our observations.
