Imaging a Central Ionized Component, a Narrow Ring, and the CO Snowline in the Multigapped Disk of HD 169142
Imaging a Central Ionized Component, a Narrow Ring, and the CO Snowline in the Multigapped Disk of HD 169142
复制标题
对 HD 169142 多间隙盘中的中心电离成分、窄环和 CO 雪线进行成像
DOI：
10.3847/1538-4357/aa6620
复制
发表时间：
2017
期刊：
影响因子：
--
通讯作者：
A. Sierra
中科院分区：
文献类型：
--
作者：
E. Macías;G. Anglada;M. Osorio;J. Torrelles;C. Carrasco;José F. Gómez;Luis F. Rodriguez;A. Sierra
我们报告了赫比格Ae星HD 169142在7毫米、9毫米和3厘米处的超大型阵列观测结果。这些观测使我们能够研究这个具有迄今为止最高角分辨率(0.“12×0.”09，或14 Au×11 Au，7 mm)的圆盘的毫米发射。我们的7毫米和9毫米图像显示了一个半径为∼25Au的狭窄发射环，跟踪着内部缝隙的外缘。这个环呈现出一种不对称的形态，它可能是由圆盘和正在形成的行星之间的动力学相互作用产生的。此外，7毫米和9毫米图像的方位平均径向强度分布证实了之前在∼45Au上报告的间隙的存在，并揭示了在∼85Au上新的间隙。我们分析了存档的DCO+(3-2)和C18O(2-1)ALMA观测结果，表明CO雪线位于这个第三个外层空隙附近。这表明，靠近CO雪线的大尘埃颗粒的生长和积累可能是造成这个提议的外部空隙的机制。最后，在朝向盘中心的7 mm、9 mm和3 cm处检测到致密的发射源。它的通量密度和光谱指数表明，它是由电离气体的自由发射所主导的，这可能与内盘、独立物体或电离喷流的光致电离有关。
We report Very Large Array observations at 7 mm, 9 mm, and 3 cm toward the pre-transitional disk of the Herbig Ae star HD 169142. These observations have allowed us to study the millimeter emission of this disk with the highest angular resolution so far (0.″12 × 0.″09, or 14 au × 11 au, at 7 mm). Our 7 and 9 mm images show a narrow ring of emission at a radius of ∼25 au tracing the outer edge of the inner gap. This ring presents an asymmetric morphology that could be produced by dynamical interactions between the disk and forming planets. Additionally, the azimuthally averaged radial intensity profiles of the 7 and 9 mm images confirm the presence of the previously reported gap at ∼45 au and reveal a new gap at ∼85 au. We analyzed archival DCO+(3–2) and C18O(2–1) ALMA observations, showing that the CO snowline is located very close to this third outer gap. This suggests that growth and accumulation of large dust grains close to the CO snowline could be the mechanism responsible for this proposed outer gap. Finally, a compact source of emission is detected at 7 mm, 9 mm, and 3 cm toward the center of the disk. Its flux density and spectral index indicate that it is dominated by free–free emission from ionized gas, which could be associated with the photoionization of the inner disk, an independent object, or an ionized jet.
影响因子：
6.5
作者：
M. Flock;J. P. Ruge;N. Dzyurkevich;T. Henning;H. Klahr;S. Wolf
通讯作者：
M. Flock;J. P. Ruge;N. Dzyurkevich;T. Henning;H. Klahr;S. Wolf