论文标题
中间质量恒星形成区域NGC 2071 IR中的磁盘和流出
Disks and Outflows in the Intermediate-mass Star Forming Region NGC 2071 IR
论文作者
论文摘要
我们提出了ALMA带6/7（1.3 mm/0.87毫米）和VLA KA带（9 mm）的观测值NGC 2071 IR，一个中间质量恒星形成区域。 We characterize the continuum and associated molecular line emission towards the most luminous protostars, i.e., IRS1 and IRS3, on ~100 au (0. 2") scales. IRS1 is partly resolved in millimeter and centimeter continuum, which shows a potential disk. IRS3 has a well resolved disk appearance in millimeter continuum and is further resolved into a close binary system separated by ~40 au at 9 MM。 1.4-1.5 $ m_ \ odot $。基于运动型模型及其频谱分布的中心质量为3-5 $ m_ \ odot $，假设它是由IRS1和IRS的单个Protostar所占据的。 IRS1，可以通过单个进取的喷气机构来更好地解释〜50 $^{\ circ} $的〜50 $^{\ circ} $。
We present ALMA band 6/7 (1.3 mm/0.87 mm) and VLA Ka band (9 mm) observations toward NGC 2071 IR, an intermediate-mass star forming region. We characterize the continuum and associated molecular line emission towards the most luminous protostars, i.e., IRS1 and IRS3, on ~100 au (0. 2") scales. IRS1 is partly resolved in millimeter and centimeter continuum, which shows a potential disk. IRS3 has a well resolved disk appearance in millimeter continuum and is further resolved into a close binary system separated by ~40 au at 9 mm. Both sources exhibit clear velocity gradients across their disk major axes in multiple spectral lines including C18O, H2CO, SO, SO2, and complex organic molecules like CH3OH, 13CH3OH and CH3OCHO. We use an analytic method to fit the Keplerian rotation of the disks, and give constraints on physical parameters with a MCMC routine. The IRS3 binary system is estimated to have a total mass of 1.4-1.5$M_\odot$. IRS1 has a central mass of 3-5$M_\odot$ based on both kinematic modeling and its spectral energy distribution, assuming that it is dominated by a single protostar. For both IRS1 and IRS3, the inferred ejection directions from different tracers, including radio jet, water maser, molecular outflow, and H2 emission, are not always consistent, and for IRS1, these can be misaligned by ~50$^{\circ}$. IRS3 is better explained by a single precessing jet. A similar mechanism may be present in IRS1 as well but an unresolved multiple system in IRS1 is also possible.
