Observations of Magnetic Fields Surrounding LkHα 101 Taken by the BISTRO Survey with JCMT-POL-2

Abstract

We report the first high spatial resolution measurement of magnetic fields surrounding LkHα 101, 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 μm is found to be mostly associated with the redshifted 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 BPOS ~ 115 μG. The mass-to-magnetic-flux ratio in critical value units, λ ~ 0.3, is the smallest among the values obtained for other regions surveyed by POL-2. This implies that the LkHα 101 region is subcritical, and the magnetic field is strong enough to prevent gravitational collapse. The inferred δB/B0 ~ 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 ± 0.03, 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 (LkHα 101) in the region. Magnetic field tangling and the joint effect of grain alignment and rotational disruption by radiative torques can potentially explain such a decreasing trend.

Metadata

Item Type:	Article
Authors/Creators:	Ngoc, NB Diep, PN Parsons, H Pattle, K Hoang, T Ward-Thompson, D Tram, LN Hull, CLH Tahani, M Furuya, R Bastien, P Qiu, K Hasegawa, T Kwon, W Doi, Y Lai, S-P Coudé, S Berry, D Ching, T-C Hwang, J Soam, A Wang, J-W Arzoumanian, D Bourke, TL Byun, D-Y Chen, H-RV Chen, Z Chen, WP Chen, M Cho, J Choi, Y Choi, M Chrysostomou, A Chung, EJ Dai, S Francesco, JD Duan, Y Duan, H-Y Eden, D Eswaraiah, C Fanciullo, L Fiege, J Fissel, LM Franzmann, E Friberg, P Friesen, R Fuller, G Gledhill, T Graves, S Greaves, J Griffin, M Gu, Q Han, I Hatchell, J Hayashi, S Houde, M Inoue, T Inutsuka, S-I Iwasaki, K Jeong, I-G Johnstone, D Kang, J-H Kang, S-J Kang, M Kataoka, A Kawabata, K Kemper, F Kim, K-T Kim, J Pyo, T-S Qian, L Rao, R Rawlings, M Rawlings, J Retter, B Richer, J Rigby, A Sadavoy, S Saito, H Savini, G Scaife, A Seta, M Kim, G Kim, S Kim, KH Kim, M-R Kirchschlager, F Kirk, J Kobayashi, MIN Koch, PM Konyves, V Kusune, T Kwon, J Lacaille, K Law, C-Y Lee, S-S Lee, Y-H Lee, C-F Lee, J-E Lee, H Lee, CW Li, D Li, H-B Li, D Liu, H-L Liu, J Liu, T Liu, S-Y Lu, X Lyo, A-R Mairs, S Matsumura, M Matthews, B Moriarty-Schieven, G Nagata, T Nakamura, F Nakanishi, H Ohashi, N Onaka, T Park, G Peretto, N Shimajiri, Y Shinnaga, H Tamura, M Tang, Y-W Tang, X Tomisaka, K Tsukamoto, Y Viti, S Wang, H Whitworth, A Xie, J Yen, H-W Yoo, H Yuan, J Yun, H-S Zenko, T Zhang, Y Zhang, C-P Zhang, G Zhou, J Zhu, L Looze, ID André, P Dowell, CD Eyres, S Falle, S https://orcid.org/0000-0002-6663-7675 Robitaille, J-F Van Loo, S https://orcid.org/0000-0003-4746-8500
Copyright, Publisher and Additional Information:	© 2021. The American Astronomical Society. All rights reserved. This is an author-created, un-copyedited version of an article published in Astrophysical Journal. IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from it. The Version of Record is available online at https://doi.org/10.3847/1538-4357/abd0fc
Keywords:	Interstellar magnetic fields; Molecular clouds; Star formation
Dates:	Published: 10 February 2021 Published (online): 8 February 2021 Accepted: 3 December 2020
Institution:	The University of Leeds
Academic Units:	The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Mathematics (Leeds) > Applied Mathematics (Leeds) The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Physics and Astronomy (Leeds) > Astrophysics (Leeds)
Depositing User:	Symplectic Publications
Date Deposited:	30 Jul 2021 08:56
Last Modified:	10 Jan 2023 11:05
Status:	Published
Publisher:	American Astronomical Society
Identification Number:	10.3847/1538-4357/abd0fc
Related URLs:	Author
Open Archives Initiative ID (OAI ID):	oai:eprints.whiterose.ac.uk:176582

CORE (COnnecting REpositories)

Observations of Magnetic Fields Surrounding LkHα 101 Taken by the BISTRO Survey with JCMT-POL-2

Abstract

Metadata

Download

Accepted Version

Export

Statistics