We report our Submillimeter Array (SMA) observations of the Class I–II protostar HL Tau in 13CO (2–1), C18O (2–1), SO(56–45), and 1.3 mm dust-continuum emission and our analyses of the ALMA long baseline data of HCO+ (1–0) emission. The 1.3 mm continuum emission observed with the SMA shows compact (~08?×?05) and extended (~65?×?43) components, tracing the protoplanetary disk and the protostellar envelope, respectively. The 13CO, C18O, and HCO+ show a compact (~200 au) component at velocities higher than 3 km s?1 from the systemic velocity and an extended (~1000 au) component at lower velocities. The high-velocity component traces the Keplerian rotating disk, and the low-velocity component traces the infalling envelope. The HCO+ high-velocity component is fitted with a Keplerian disk model with a central stellar mass of 1.4 M ⊙. The radial intensity profiles of 13CO and C18O along the disk major axis are fitted with a disk+envelope model, and the gas masses of the disk and envelope are estimated to be (2–40) × 10–4 M ⊙ and M ⊙, respectively. The disk dust mass has been estimated to be (1–3)?×?10?3 M ⊙ in the literature. Thus, our estimated disk gas mass suggests that the gas-to-dust mass ratio in the disk is.
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机译:我们报告了在13CO(2-1),C18O(2-1),SO(56-45)和1.3 mm连续粉尘排放中I–II类原恒星HL Tau的亚毫米波阵列(SMA)观测结果以及我们的分析HMA +(1–0)排放的ALMA长基线数据。用SMA观测到的1.3 mm连续辐射显示出紧凑的(〜08?×?05)和扩展的(〜65?×?43)分量,分别追踪到原行星盘和原星包膜。 13CO,C18O和HCO +在高于系统速度的3 km s?1处显示出紧凑的(〜200 au)分量,而在较低的速度下显示出扩展的(〜1000 au)分量。高速分量跟踪开普勒旋转圆盘,而低速分量跟踪下降的包络线。 HCO +高速组件装有Keplerian圆盘模型,其中心恒星质量为1.4 M⊙。用圆盘+包络模型拟合13CO和C18O沿圆盘主轴的径向强度分布,圆盘和封套的气体质量估计为(2–40)×10–4 M⊙和M⊙,分别。在文献中,盘尘质量估计为(1-3)×××10×3 M M⊙。因此,我们估计的磁盘气体质量表明磁盘中的气尘质量比为。
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