论文标题
湍流和积聚:B5丝的高分辨率研究
Turbulence and Accretion: a High-resolution Study of the B5 Filaments
论文作者
论文摘要
对珀尔修斯B5“核心”的高分辨率观察以前已经表明,该亚音速区域实际上是由几根细丝组成的,这些细丝可能是在形成四倍体恒星系统的过程中。由于认为亚音速丝是通过湍流压缩以$ \ sim 0.1 $ PC Sonic量表生产的,因此一项详细的运动学研究对于在核心和恒星形成的背景下测试这种情况至关重要。在这里,我们使用VLA和GBT组合的观测值介绍了B5丝的详细运动随访研究,该研究以0.009 PC分辨率进行了分辨率。使用精确鉴定的细丝刺,我们发现每个细丝的平均宽度曲线和类似掉落的功能之间的相似之处很大,其中丝具有$ \ sim 0.03 $ pc的FWHM宽度。细丝的速度分散曲线也显示出对细丝刺的趋势下降。此外,B5中的速度梯度场似乎是局部有序的($ \ sim 0.04 $ PC),但全球复杂,运动行为表明,表明对细丝上的不均匀湍流积聚,并沿着一丝丝状的局部过度密度朝向局部过度。
High-resolution observations of the Perseus B5 "core" have previously revealed that this subsonic region actually consists of several filaments that are likely in the process of forming a quadruple stellar system. Since subsonic filaments are thought to be produced at the $\sim 0.1$ pc sonic scale by turbulent compression, a detailed kinematic study is crucial to test such a scenario in the context of core and star formation. Here we present a detailed kinematic follow-up study of the B5 filaments at a 0.009 pc resolution using the VLA and GBT combined observations fitted with multi-component spectral models. Using precisely identified filament spines, we find a remarkable resemblance between the averaged width profiles of each filament and Plummer-like functions, with filaments possessing FWHM widths of $\sim 0.03$ pc. The velocity dispersion profiles of the filaments also show decreasing trends towards the filament spines. Moreover, the velocity gradient field in B5 appears to be locally well ordered ($\sim 0.04$ pc) but globally complex, with kinematic behaviors suggestive of inhomogeneous turbulent accretion onto filaments and longitudinal flows towards a local overdensity along one of the filaments.