arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2007.15436astro-ph.GAastro-ph.SR
收藏

南冕座分子云复合体中致密核SL42（CrA-E）的磁场畸变

Distortion of Magnetic Fields in the Dense Core SL42 (CrA-E) in the Corona Australis Molecular Cloud Complex

Ryo Kandori, Motohide Tamura, Masao Saito, Kohji Tomisaka, Tomoaki Matsumoto, Ryo Tazaki, Tetsuya Nagata, Nobuhiko Kusakabe, Yasushi Nakajima, Jungmi Kwon, Taka… 展开作者

Ryo Kandori, Motohide Tamura, Masao Saito, Kohji Tomisaka, Tomoaki Matsumoto, Ryo Tazaki, Tetsuya Nagata, Nobuhiko Kusakabe, Yasushi Nakajima, Jungmi Kwon, Takahiro Nagayama, Ken'ichi Tatematsu

备注：
23 pages, 12 figures, accepted for publication in ApJ; For the convenience of readers, we explained our procedures of various data calibration/reduction/analysis methods again in this paper, instead of omitting detailed explanations by citing our previous papers
阅读 PDF
arXiv 页面 ↗HTML 原文 ↗

AI总结：

本文利用近红外偏振观测和沙漏磁场模型研究致密核SL42的磁场结构，发现其磁场弯曲、强度约22.4 μG，临界质量与观测质量接近，表明该核处于接近临界坍缩状态。

摘要：

基于背景星的近红外偏振观测，通过测量磁排列尘埃颗粒产生的二向色偏振光，研究了南冕座分子云复合体中致密核SL42（CrA-E）的详细磁场结构。利用206颗恒星绘制了SL42内部及其周围的磁场图，并识别出弯曲的磁场。在简单沙漏（抛物线）磁场模型的基础上，估计该核在天球平面上的磁轴为$40^{\circ} \pm 3^{\circ}$。发现SL42的天球平面磁场强度为$22.4 \pm 13.9$ $μ$G。考虑热/湍流压力和天球平面磁场分量的影响，得到SL42的临界质量为$M_{\rm cr} = 21.2 \pm 6.6$ M$_{\odot}$，这与观测到的核质量$M_{\rm core} \approx 20$ M$_{\odot}$接近。因此我们得出结论：如果磁场接近天球平面，SL42处于接近临界状态的条件。由于在SL42中心存在一个极低光度天体（VeLLO），该核不太可能处于高度亚临界状态（即磁倾角显著偏离天球平面）。该核可能从接近运动学临界状态开始坍缩。除沙漏磁场模型外，Inoue \\& Fukui（2013）机制或许可以解释SL42区域弯曲磁场的起源。

英文摘要：

Detailed magnetic field structure of the dense core SL42 (CrA-E) in the Corona Australis molecular cloud complex was investigated based on near-infrared polarimetric observations of background stars to measure dichroically polarized light produced by magnetically aligned dust grains. The magnetic fields in and around SL42 were mapped using 206 stars and curved magnetic fields were identified. On the basis of simple hourglass (parabolic) magnetic field modeling, the magnetic axis of the core on the plane of sky was estimated to be $40^{\circ} \pm 3^{\circ}$. The plane-of-sky magnetic field strength of SL42 was found to be $22.4 \pm 13.9$ $μ$G. Taking into account the effects of thermal/turbulent pressure and the plane-of-sky magnetic field component, the critical mass of SL42 was obtained to be $M_{\rm cr} = 21.2 \pm 6.6$ M$_{\odot}$, which is close to the observed core mass of $M_{\rm core} \approx 20$ M$_{\odot}$. We thus conclude that SL42 is in a condition close to the critical state if the magnetic fields lie near the plane of the sky. Since there is a very low luminosity object (VeLLO) toward the center of SL42, it is unlikely this core is in a highly subcritical condition (i.e., magnetic inclination angle significantly deviated from the plane of sky). The core probably started to collapse from a nearly kinematically critical state. In addition to the hourglass magnetic field modeling, the Inoue \& Fukui (2013) mechanism may explain the origin of the curved magnetic fields in the SL42 region.

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

↑