Observations of magnetic fields surrounding LkH$α$ 101 taken by the BISTRO survey with JCMT-POL-2
Creators: name: Ngoc, Nguyen Bich
name: Diep, Pham Ngoc
name: Parsons, Harriet
name: Pattle, Kate
name: Hoang, Thiem
name: Ward-Thompson, Derek
name: Tram, Le Ngoc
name: Hull, Charles L. H.
name: Tahani, Mehrnoosh
name: Furuya, Ray
name: Bastien, Pierre
name: Qiu, Keping
name: Hasegawa, Tetsuo
name: Kwon, Woojin
name: Doi, Yasuo
name: Lai, Shih-Ping
name: Coude, Simon
name: Berry, David
name: Ching, Tao-Chung
name: Hwang, Jihye
name: Soam, Archana
name: Wang, Jia-Wei
name: Arzoumanian, Doris
name: Bourke, Tyler L.
name: Byun, Do-Young
name: Chen, Huei-Ru Vivien
name: Chen, Zhiwei
name: Chen, Wen Ping
name: Chen, Mike
name: Cho, Jungyeon
name: Choi, Yunhee
name: Choi, Minho
name: Chrysostomou, Antonio
name: Chung, Eun Jung
name: Dai, Sophia
name: Di Francesco, James
name: Duan, Yan
name: Duan, Hao-Yuan
name: Eden, David
name: Eswaraiah, Chakali
name: Fanciullo, Lapo
name: Fiege, Jason
name: Fissel, Laura M.
name: Franzmann, Erica
name: Friberg, Per
name: Friesen, Rachel
name: Fuller, Gary
name: Gledhill, Tim
name: Graves, Sarah
name: Greaves, Jane
name: Griffin, Matt
name: Gu, Qilao
name: Han, Ilseung
name: Hatchell, Jennifer
name: Hayashi, Saeko
name: Houde, Martin
name: Inoue, Tsuyoshi
name: Inutsuka, Shu-ichiro
name: Iwasaki, Kazunari
name: Jeong, Il-Gyo
name: Johnstone, Doug
name: Kang, Ji-hyun
name: Kang, Sung-ju
name: Kang, Miju
name: Kataoka, Akimasa
name: Kawabata, Koji
name: Kemper, Francisca
name: Kim, Kee-Tae
name: Kim, Jongsoo
name: Pyo, Tae-Soo
name: Qian, Lei
name: Rao, Ramprasad
name: Rawlings, Mark
name: Rawlings, Jonathan
name: Retter, Brendan
name: Richer, John
name: Rigby, Andrew
name: Sadavoy, Sarah
name: Saito, Hiro
name: Savini, Giorgio
name: Scaife, Anna
name: Seta, Masumichi
name: Kim, Gwanjeong
name: Kim, Shinyoung
name: Kim, Kyoung Hee
name: Kim, Mi-Ryang
name: Kirchschlager, Florian
name: Kirk, Jason
name: Kobayashi, Masato I. N.
name: Koch, Patrick M.
name: Konyves, Vera
name: Kusune, Takayoshi
name: Kwon, Jungmi
name: Lacaille, Kevin
name: Law, Chi-Yan
name: Lee, Sang-Sung
name: Lee, Yong-Hee
name: Lee, Chin-Fei
name: Lee, Jeong-Eun
name: Lee, Hyeseung
name: Lee, Chang Won
name: Li, Di
name: Li, Hua-bai
name: Li, Dalei
name: Liu, Hong-Li
name: Liu, Junhao
name: Liu, Tie
name: Liu, Sheng-Yuan
name: Lu, Xing
name: Lyo, A-Ran
name: Mairs, Steve
name: Matsumura, Masafumi
name: Matthews, Brenda
name: Moriarty-Schieven, Gerald
name: Nagata, Tetsuya
name: Nakamura, Fumitaka
name: Nakanishi, Hiroyuki
name: Ohashi, Nagayoshi
name: Onaka, Takashi
name: Park, Geumsook
name: Peretto, Nicolas
name: Shimajiri, Yoshito
name: Shinnaga, Hiroko
name: Tamura, Motohide
name: Tang, Ya-Wen
name: Tang, Xindi
name: Tomisaka, Kohji
name: Tsukamoto, Yusuke
name: Viti, Serena
name: Wang, Hongchi
name: Whitworth, Anthony
name: Xie, Jinjin
name: Yen, Hsi-Wei
name: Yoo, Hyunju
name: Yuan, Jinghua
name: Yun, Hyeong-Sik
name: Zenko, Tetsuya
name: Zhang, Yapeng
name: Zhang, Chuan-Peng
name: Zhang, Guoyin
name: Zhou, Jianjun
name: Zhu, Lei
name: de Looze, Ilse
name: Andre, Philippe
name: Dowell, C. Darren
name: Eyres, Stewart
name: Falle, Sam
name: Robitaille, Jean-Francois
name: van Loo, Sven
Publisher: name: arXiv
Year: 2020
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: 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.
description: 25 pages, 19 figures, Accepted for publication in The Astrophysical Journal