论文标题
对LKH $α$α$ 101的磁场观察，该bistro调查与JCMT-POL-2一起进行
Observations of magnetic fields surrounding LkH$α$ 101 taken by the BISTRO survey with JCMT-POL-2
论文作者
论文摘要
我们报告了LKH $α$ 101的磁场的第一个高空间分辨率测量，这是Auriga-California分子云的一部分。在詹姆斯·麦克斯韦（James Clerk Maxwell）望远镜（BISTRO）调查中，在B场的框架内，在James Clerk Maxwell望远镜（BISTRO）框架内使用POL-2偏振仪进行观察。发现在850 $μ$ m处观察到的热灰尘发射的极化主要与云的红移气体成分有关。磁场显示相对复杂的形态。 Davis-Chandrasekhar-Fermi方法的两种变体，即UNSHARP屏蔽和结构函数，用于计算天空平面中磁场的强度，从而产生$ b _ {\ rm pos} \ sim 115 $ $ $ $ $ \ $ \mathrmμ$ g的相似结果。关键值单位的质量磁通量比率为$λ\ sim0.3 $，是POL-2调查的其他地区获得的值中最小的。这意味着LKH $α$ 101区域是亚临界区域，磁场足够强以防止重力塌陷。推断的$ΔB/b_0 \ sim 0.3 $表示磁场的大规模组成部分主导了湍流。幂律的变化可以由$α= 0.82 \ pm0.03 $的幂律拟合，该指数在先前报道的分子云的范围内。我们发现，随着该地区唯一的早期B恒星（LKH $α$ 101）的距离，极化分数迅速减少。磁场缠结以及晶粒比对的关节效应和辐射扭矩的旋转破坏是解释这种减少趋势的潜力。
We report the first high spatial resolution measurement of magnetic fields surrounding LkH$α$ 101, a part of the Auriga-California molecular cloud. The observations were taken with the POL-2 polarimeter on the James Clerk Maxwell Telescope within the framework of the B-fields In Star-forming Region Observations (BISTRO) survey. Observed polarization of thermal dust emission at 850 $μ$m is found to be mostly associated with the red-shifted gas component of the cloud. The magnetic field displays a relatively complex morphology. Two variants of the Davis-Chandrasekhar-Fermi method, unsharp masking and structure function, are used to calculate the strength of magnetic fields in the plane of the sky, yielding a similar result of $B_{\rm POS}\sim 115$ $\mathrmμ$G. The mass-to-magnetic-flux ratio in critical value units, $λ\sim0.3$, is the smallest among the values obtained for other regions surveyed by POL-2. This implies that the LkH$α$ 101 region is sub-critical and the magnetic field is strong enough to prevent gravitational collapse. The inferred $δB/B_0\sim 0.3$ implies that the large scale component of the magnetic field dominates the turbulent one. The variation of the polarization fraction with total emission intensity can be fitted by a power-law with an index of $α=0.82\pm0.03$, which lies in the range previously reported for molecular clouds. We find that the polarization fraction decreases rapidly with proximity to the only early B star (LkH$α$ 101) in the region. The magnetic field tangling and the joint effect of grain alignment and rotational disruption by radiative torques are potential of explaining such a decreasing trend.
