论文标题
在0年的内部100 au区域中，磁性磁盘形成0年轻恒星对象OMC-3/mms〜6由JVLA和ALMA解决
Magnetically regulated disk-formation in the inner 100 au region of the Class 0 young stellar object OMC-3/MMS~6 resolved by JVLA and ALMA
论文作者
论文摘要
我们已经对档案JVLA（$ \ sim $ 9毫米）进行了极化校准，对0级年轻恒星对象（YSO）OMC-3/mms 6（也称为HOPS-87），然后与档案ALMA 1.2 mm的观测值进行比较。我们发现，OMC-3/mms 6的最内向的$ \ sim $ 100 AU区域可能非常厚（例如，$τ\ gg $ 1），$ \ sim $ 1毫米波长，因此主导的极化机制是二甲级灭绝。它在$ \ sim $ 9毫米波长时略有光学上的薄（例如，$τ\ sillsim $ 1），因此JVLA观察值可以直接从非球形灰尘探测线性极化的发射。假设预计的灰尘晶粒的长轴是垂直于磁场（B场）线对准的，我们建议整个B场拓扑类似于一个沙漏的形状，而此“沙漏”出现$ \ sim $ 40 $^{\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ field拓扑。该系统的几何形状与磁调节的致密（伪）磁盘一致。基于观察到的29.45 GHz通量密度，并假设吸收灰尘的不透明性$κ^{abs} _ {29.45 \，GHz} = $ 0.0096 cm $ $^{2} $ g $ g $ g $^{ - 1} $，$ \ sim $ 43 au $ $ $ $ $ $ \ y $ 140000 $ \ m. From this case study, it appears to us that some previous 9 mm surveys towards Class 0/I YSOs might have systematically underestimated dust masses by one order of magnitude, owing to that they assumed the too high dust absorption opacity ($\sim$0.1 cm$^{2}$ g$^{-1}$) for $\sim$9 mm wavelengths but without self-consistently considering the dust scattering不透明度。
We have carried out polarization calibration for archival JVLA ($\sim$9 mm) full polarization observations towards the Class 0 young stellar object (YSO) OMC-3/MMS 6 (also known as HOPS-87), and then compared with the archival ALMA 1.2 mm observations. We found that the innermost $\sim$100 au region of OMC-3/MMS 6 is likely very optically thick (e.g., $τ\gg$1) at $\sim$1 mm wavelength such that the dominant polarization mechanism is dichroic extinction. It is marginally optically thin (e.g., $τ\lesssim$1) at $\sim$9 mm wavelength such that the JVLA observations can directly probe the linearly polarized emission from non-spherical dust. Assuming that the projected long axis of dust grains is aligned perpendicular to magnetic field (B-field) lines, we propose that the overall B-field topology resembles an hourglass shape, while this "hourglass" appears $\sim$40$^{\circ}$ inclined with respect to the previously reported outflow axis. The geometry of this system is consistent with a magnetically regulated dense (pseudo-)disk. Based on the observed 29.45 GHz flux density and assuming a dust absorption opacity $κ^{abs}_{29.45\,GHz}=$0.0096 cm$^{2} $g$^{-1}$, the derived overall dust mass within a $\sim$43 au radius is $\sim$14000 $M_{\oplus}$. From this case study, it appears to us that some previous 9 mm surveys towards Class 0/I YSOs might have systematically underestimated dust masses by one order of magnitude, owing to that they assumed the too high dust absorption opacity ($\sim$0.1 cm$^{2}$ g$^{-1}$) for $\sim$9 mm wavelengths but without self-consistently considering the dust scattering opacity.
