Kinematics around the B335 protostar down to au scales
Kinematics around the B335 protostar down to au scales
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B335 原恒星周围的运动学小至 au 尺度
DOI：
10.1051/0004-6361/201935948
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发表时间：
2019
影响因子：
6.5
通讯作者：
Persson, Magnus V.
中科院分区：
文献类型：
--
作者：
Bjerkeli, Per;Ramsey, Jon P.;Harsono, Daniel;Calcutt, Hannah;Kristensen, Lars E.;van der Wiel, Matthijs H.;Jørgensen, Jes K.;Muller, Sébastien;Persson, Magnus V.
外流发射和年轻恒星周围吸积盘的形成之间的关系仍然没有完全理解，这就是为什么需要光谱和空间分辨观测。最近，阿塔卡马大型毫米/亚毫米阵列（阿尔马）进行了长基线观测对少数年轻的来源，揭示了外流和内部区域的disks.AimsHere的连接，我们的目标是确定小尺度的运动学和形态学特性的外流从孤立的原恒星B335没有开普勒磁盘，到目前为止，被观察到的规模下降到10 Au。MethodsWe使用阿尔马在其最长的基线配置，观察排放CO同位素，SiO，SO2，和CH 3OH。B335的接近提供了~3 Au（0.03 "）的分辨率。我们还结合我们的长基线数据与档案观测，以产生一个高保真度的图像，覆盖规模高达700 Au（7 "）。结果12 CO具有X形的形态与臂的宽度约50 Au，我们与流出腔的壁，类似于在更大的尺度上观察到的。长基线连续辐射局限于距离原恒星<7 Au，而短基线连续辐射则跟随12 CO流出和空腔壁。在原恒星的~30 Au范围内检测到甲醇。在原恒星附近也检测到SiO，但沿着流出物沿着延伸。结论在距离原恒星约30 Au处，12 CO流出物没有明显的旋转迹象。SiO在小尺度上跟踪原恒星喷流，但没有明显的旋转。CH_3OH和SO_2在一个直径小于16 Au的区域内跟踪，该区域以连续峰为中心，明显地旋转。使用情节，高速，12 CO功能，我们估计发射半径的外流是<0.1 Au和动力学的时间尺度的顺序为几年。
ContextThe relationship between outflow launching and the formation of accretion disks around young stellar objects is still not entirely understood, which is why spectrally and spatially resolved observations are needed. Recently, the Atacama Large Millimetre/sub-millimetre Array (ALMA) carried out long-baseline observations towards a handful of young sources, revealing connections between outflows and the inner regions of disks.AimsHere we aim to determine the small-scale kinematical and morphological properties of the outflow from the isolated protostar B335 for which no Keplerian disk has, so far, been observed on scales down to 10 au.MethodsWe used ALMA in its longest-baseline configuration to observe emission from CO isotopologues, SiO, SO2, and CH3OH. The proximity of B335 provides a resolution of ~3 au (0.03′′). We also combined our long-baseline data with archival observations to produce a high-fidelity image covering scales up to 700 au (7′′).Results12CO has an X-shaped morphology with arms ~50 au in width that we associate with the walls of an outflow cavity, similar to what is observed on larger scales. Long-baseline continuum emission is confined to <7 au from the protostar, while short-baseline continuum emission follows the12CO outflow and cavity walls. Methanol is detected within ~30 au of the protostar. SiO is also detected in the vicinity of the protostar, but extended along the outflow.ConclusionsThe12CO outflow does not show any clear signs of rotation at distances ≳30 au from the protostar. SiO traces the protostellar jet on small scales, but without obvious rotation. CH3OH and SO2trace a region <16 au in diameter, centred on the continuum peak, which is clearly rotating. Using episodic, high-velocity,12CO features, we estimate the launching radius of the outflow to be <0.1 au and dynamical timescales of the order of a few years.
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B335 最内层包络线的运动学和物理条件
DOI：
10.1088/0004-637x/742/1/57
发表时间：
2011
期刊：
The Astrophysical Journal
影响因子：
--
作者：
Hsi;S. Takakuwa;N. Ohashi
通讯作者：
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影响因子：
6.5
作者：
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通讯作者：
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影响因子：
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作者：
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通讯作者：
Li, Zhi-Yun
DOI：
10.1086/161481
发表时间：
1983-11
期刊：
The Astrophysical Journal
影响因子：
--
作者：
R. Pudritz;C. Norman
通讯作者：
R. Pudritz;C. Norman
赫歇尔恒星形成区域的水（WISH）
影响因子：
6.5
作者：
J. Mottram;L. Kristensen;E. V. Dishoeck;S. Bruderer;I. S. Jose;A. Karska;R. Visser;G. Santangelo;A. Benz;E. Bergin;P. Caselli;F. Herpin;M. Hogerheijde;D. Johnstone;T. V. Kempen;R. Liseau;B. Nisini;M. Tafalla;F. V. D. Tak;F. V. D. Tak;F. Wyrowski
通讯作者：
F. Wyrowski