论文标题
星际云中的磁场形态与速度梯度技术
Magnetic Field Morphology in Interstellar Clouds with the Velocity Gradient Technique
论文作者
论文摘要
磁场虽然在许多天体物理环境中无处不在,但在观察中的测量很具有挑战性。基于磁化湍流中涡流各向异性的特性,速度梯度技术是一种与粉尘极化法的方法,能够追踪天际磁场的磁场,测量星际介质的磁化并估算使用光谱构图中的分子构图中引力崩溃气体的分数。在本文中,我们将此技术应用于古尔德带中的五个低质量恒星形成的分子云,并将结果与从极化灰尘发射获得的磁场方向进行比较。我们发现两种方法的磁场方向的估计值和磁化均在统计上相似。我们估计所选云中崩溃的气体的分数。通过速度梯度技术,我们还提出了史密斯云的天空平面磁场方向和磁化,为此,灰尘偏振仪数据不可用。
Magnetic fields, while ubiquitous in many astrophysical environments, are challenging to measure observationally. Based on the properties of anisotropy of eddies in magnetized turbulence, the Velocity Gradient Technique is a method synergistic to dust polarimetry that is capable of tracing plane-of-the-sky magnetic field, measuring the magnetization of interstellar media and estimating the fraction of gravitational collapsing gas in molecular clouds using spectral line observations. In this paper, we apply this technique to five low-mass star-forming molecular clouds in the Gould Belt and compare the results to the magnetic-field orientation obtained from polarized dust emission. We find the estimates of magnetic field orientations and magnetization for both methods are statistically similar. We estimate the fraction of collapsing gas in the selected clouds. By means of the Velocity Gradient Technique, we also present the plane-of-the-sky magnetic field orientation and magnetization of the Smith cloud, for which dust polarimetry data are unavailable.