论文标题
加利福尼亚L1482云中的细丝旋转
Filament rotation in the California L1482 cloud
论文作者
论文摘要
我们分析了加利福尼亚分子云（CMC）L1482细丝的气体质量分布，气体运动学和年轻恒星对象（YSO）含量。我们得出511 $^{+17} _ { - 16} $ PC的Gaia Dr2 ySO距离。我们为平均气体质量（M/L）概况得出无标度的幂律；我们计算与这些相一致的重力和场曲线。我们提出IRAM 30 m c $^{18} $ O（1-0）（和其他示踪剂）位置 - 速度（PV）图，显示出复杂的速度扭曲和转弯结构。我们在C $^{18} $ O垂直于Southern Filment Ridgeline中找到一个旋转轮廓。该配置文件是常规的，限制的（$ r \ lyssim0.4 $ pc），反对称，并且以$ r \ sim0.25 $ PC的休息为单位线性。内部（外部）梯度的时间尺度为$ \ sim $ 0.7（6.0）MYR。我们表明，与重力相比，中心力向断裂增加。当力之比接近统一时，剖面在实现细丝破裂之前就翻转了。重力与旋转的时间标准和相对作用表明该结构是稳定的，长期存在的（$ \ sim $几次6 Myr），并且经历了外部进化。此外，这种丝实际上没有恒星形成，垂直的普朗克磁场（POS）磁场形态和POS“ Zig-Zag”形态，它与旋转曲线一起导致了3D形状是带有螺旋磁场的软木丝丝。这些结果及其在猎户座和G035.39-00.33中的结果，表明旋转细丝的较高密度的进化偏向角动量。因此，磁场可能是高质量（M $ \ sim10^5 $ m $ _ {\ odot} $）的基本特征。
We analyze the gas mass distribution, the gas kinematics, and the young stellar object (YSO) content of the California Molecular Cloud (CMC) L1482 filament. We derive a Gaia DR2 YSO distance of 511$^{+17}_{-16}$ pc. We derive scale-free power-laws for the mean gas line-mass (M/L) profiles; we calculate the gravitational potential and field profiles consistent with these. We present IRAM 30 m C$^{18}$O (1-0) (and other tracers) position-velocity (PV) diagrams that exhibit complex velocity twisting and turning structures. We find a rotational profile in C$^{18}$O perpendicular to the southern filament ridgeline. The profile is regular, confined ($r\lesssim0.4$ pc), anti-symmetric, and to first order linear with a break at $r\sim0.25$ pc. The timescales of the inner (outer) gradients are $\sim$0.7 (6.0) Myr. We show that the centripetal force, compared to gravity, increases toward the break; when the ratio of forces approaches unity, the profile turns over, just before filament breakup is achieved. The timescales and relative roles of gravity to rotation indicate that the structure is stable, long lived ($\sim$ a few times 6 Myr), and undergoing outside-in evolution. Moreover, this filament has practically no star formation, a perpendicular Planck plane-of-the-sky (POS) magnetic field morphology, and POS "zig-zag" morphology, which together with the rotation profile lead to the suggestion that the 3D shape is a corkscrew filament with a helical magnetic field. These results, combined with results in Orion and G035.39-00.33, suggest evolution toward higher densities as rotating filaments shed angular momentum. Thus, magnetic fields may be an essential feature of high-mass (M $\sim10^5$ M$_{\odot}$) cloud filament evolution toward cluster formation.
