Dust polarized emission observations of NGC 6334: BISTRO reveals the details of the complex but organized magnetic field structure of the high-mass star-forming hub-filament network
Journal article, 2021

Context.
Molecular filaments and hubs have received special attention recently thanks to new studies showing their key role in star formation. While the (column) density and velocity structures of both filaments and hubs have been carefully studied, their magnetic field (B-field) properties have yet to be characterized. Consequently, the role of B-fields in the formation and evolution of hub-filament systems is not well constrained. Aims. We aim to understand the role of the B-field and its interplay with turbulence and gravity in the dynamical evolution of the NGC 6334 filament network that harbours cluster-forming hubs and high-mass star formation.
Methods.
We present new observations of the dust polarized emission at 850 μm toward the 2 pc × 10 pc map of NGC 6334 at a spatial resolution of 0.09 pc obtained with the James Clerk Maxwell Telescope (JCMT) as part of the B-field In STar-forming Region Observations (BISTRO) survey. We study the distribution and dispersion of the polarized intensity (PI), the polarization fraction (PF), and the plane-of-The-sky B-field angle (χB_POS) toward the whole region, along the 10 pc-long ridge and along the sub-filaments connected to the ridge and the hubs. We derived the power spectra of the intensity and χBPOS along the ridge crest and compared them with the results obtained from simulated filaments.
Results.
The observations span 3 orders of magnitude in Stokes I and PI and 2 orders of magnitude in PF (from 0.2 to 20%). A large scatter in PI and PF is observed for a given value of I. Our analyses show a complex B-field structure when observed over the whole region ( 10 pc); however, at smaller scales (1 pc), χBPOS varies coherently along the crests of the filament network. The observed power spectrum of χBPOS can be well represented with a power law function with a slope of-1.33 ± 0.23, which is 20% shallower than that of I. We find that this result is compatible with the properties of simulated filaments and may indicate the physical processes at play in the formation and evolution of star-forming filaments. Along the sub-filaments, χBPOS rotates frombeing mostly perpendicular or randomly oriented with respect to the crests to mostly parallel as the sub-filaments merge with the ridge and hubs. This variation of the B-field structure along the sub-filaments may be tracing local velocity flows of infalling matter in the ridge and hubs. Our analysis also suggests a variation in the energy balance along the crests of these sub-filaments, from magnetically critical or supercritical at their far ends to magnetically subcritical near the ridge and hubs. We also detect an increase in PF toward the high-column density (NH2 â 1023 cm-2) star cluster-forming hubs. These latter large PF values may be explained by the increase in grain alignment efficiency due to stellar radiation from the newborn stars, combined with an ordered B-field structure.
Conclusions.
These observational results reveal for the first time the characteristics of the small-scale (down to 0.1 pc) B-field structure of a 10 pc-long hub-filament system. Our analyses show variations in the polarization properties along the sub-filaments that may be tracing the evolution of their physical properties during their interaction with the ridge and hubs. We also detect an impact of feedback from young high-mass stars on the local B-field structure and the polarization properties, which could put constraints on possible models for dust grain alignment and provide important hints as to the interplay between the star formation activity and interstellar B-fields.

Polarization

ISM: clouds

ISM: magnetic fields

Submillimeter: ISM

Stars: formation

ISM: structure

Author

Doris Arzoumanian

University of Porto

Ray S. Furuya

Tokushima University

Tetsuo Hasegawa

National Astronomical Observatory of Japan

M. Tahani

National Research Council Canada

S. I. Sadavoy

Queen's University

Charles L. H. Hull

National Astronomical Observatory of Japan

D. Johnstone

National Research Council Canada

Patrick M. Koch

Academia Sinica

Shu-Ichiro Inutsuka

Nagoya University

Yasuo Doi

University of Tokyo

Thiem Hoang

Korea Astronomy and Space Science Institute

Takashi Onaka

Meisei University

University of Tokyo

Kazunari Iwasaki

National Astronomical Observatory of Japan

Yoshito Shimajiri

National Astronomical Observatory of Japan

Tsuyoshi Inoue

Nagoya University

Nicolas Peretto

Cardiff University

P. André

University Paris-Saclay

Pierre Bastien

Université de Montréal

David Berry

East Asian Observatory

Huei-Ru Vivien Chen

Academia Sinica

J. Di Francesco

National Research Council Canada

Chakali Eswaraiah

Chinese Academy of Sciences

Lapo Fanciullo

Academia Sinica

Laura M. Fissel

Queen's University

Jihye Hwang

Korea Astronomy and Space Science Institute

Ji-hyun Kang

Korea Astronomy and Space Science Institute

Gwanjeong Kim

National Astronomical Observatory of Japan

Kee-Tae Kim

Korea Astronomy and Space Science Institute

F. Kirchschlager

University College London (UCL)

Woojin Kwon

Seoul National University

C.W. Lee

Korea Astronomy and Space Science Institute

Hong-Li Liu

Yunnan University

A. Lyo

Korea Astronomy and Space Science Institute

Kate Pattle

National University of Ireland

Archana Soam

Universities Space Research Association

X. D. Tang

Chinese Academy of Sciences

Anthony Whitworth

Cardiff University

Tao-Chung Ching

Chinese Academy of Sciences

Simon Coudé

Universities Space Research Association

Jia-Wei Wang

Academia Sinica

D. Ward-Thompson

University of Central Lancashire

Shih-Ping Lai

Academia Sinica

Keping Qiu

Nanjing University

T. L. Bourke

SKA Organisation

Do Young Byun

Korea Astronomy and Space Science Institute

Michael Chun-Yuan Chen

University of Victoria

Zhiwei Chen

Chinese Academy of Sciences

Wen Ping Chen

National Central University

Jungyeon Cho

Chungnam National University

Yunhee Choi

Korea Astronomy and Space Science Institute

Minho Choi

Korea Astronomy and Space Science Institute

A. Chrysostomou

SKA Organisation

Eun Jung Chung

Chungnam National University

Sophia Dai

Chinese Academy of Sciences

Pham Ngoc Diep

Vietnam Academy of Science and Technology

Hao-Yuan Duan

National Tsing Hua University

Yan Duan

Chinese Academy of Sciences

D. J. Eden

Liverpool John Moores University

J. Fiege

University of Manitoba

Erica Franzmann

University of Manitoba

P. Friberg

East Asian Observatory

G. A. Fuller

University of Manchester

T. Gledhill

University of Hertfordshire

Sarah F. Graves

East Asian Observatory

J. S. Greaves

Cardiff University

Matt Griffin

Cardiff University

Qilao Gu

Chinese University of Hong Kong

Ilseung Han

Korea Astronomy and Space Science Institute

J. Hatchell

University of Exeter

S. Hayashi

National Astronomical Observatory of Japan

Il-Gyo Jeong

Korea Astronomy and Space Science Institute

Miju Kang

Korea Astronomy and Space Science Institute

Sung-Ju Kang

Korea Astronomy and Space Science Institute

Akimasa Kataoka

National Astronomical Observatory of Japan

K. Kawabata

Hiroshima University

F. Kemper

Academia Sinica

Mi-Ryang Kim

Korea Astronomy and Space Science Institute

Kyoung Hee Kim

Korea Astronomy and Space Science Institute

Jongsoo Kim

Korea Astronomy and Space Science Institute

Shinyoung Kim

Korea Astronomy and Space Science Institute

J. Kirk

University of Central Lancashire

Masato I. N. Kobayashi

Tohoku University

Vera Konyves

University of Central Lancashire

Takayoshi Kusune

National Astronomical Observatory of Japan

Jungmi Kwon

University of Tokyo

Kevin Lacaille

McMaster University

Chi Yan Law

Astronomy and plasmaphysics 2

Chinese University of Hong Kong

Chin-Fei Lee

Academia Sinica

Yong-Hee Lee

East Asian Observatory

Sang Sung Lee

Korea Astronomy and Space Science Institute

H. Lee

Chungnam National University

Jeong Eun Lee

Kyung Hee University

Hua-Bai Li

Chinese University of Hong Kong

D. Li

Chinese Academy of Sciences

Dalei Li

Chinese Academy of Sciences

J. Liu

Nanjing University

Tie Liu

Shanghai Astronomical Observatory

Sheng-Yuan Liu

Academia Sinica

X. Lu

National Astronomical Observatory of Japan

Steve Mairs

East Asian Observatory

Masafumi Matsumura

Kagawa University

B. C. Matthews

National Research Council Canada

Gerald H. Moriarty-Schieven

National Research Council Canada

Tetsuya Nagata

Kyoto University

Fumitaka Nakamura

National Astronomical Observatory of Japan

Hiroyuki Nakanishi

Kagoshima University

Nguyen Bich Ngoc

Vietnam Academy of Science and Technology

Nagayoshi Ohashi

National Astronomical Observatory of Japan

G. Park

Korea Astronomy and Space Science Institute

Harriet Parsons

East Asian Observatory

Tae-Soo Pyo

National Astronomical Observatory of Japan

Lei Qian

Chinese Academy of Sciences

R. Rao

Academia Sinica

J. M.C. Rawlings

University College London (UCL)

M.G. Rawlings

East Asian Observatory

Brendan Retter

Cardiff University

J. Richer

University of Cambridge

Andrew Rigby

Cardiff University

Hiro Saito

University of Tsukuba

G. Savini

University College London (UCL)

A. M. M. Scaife

University of Manchester

Masumichi Seta

Kwansei Gakuin University

H. Shinnaga

Kagoshima University

Motohide Tamura

National Astronomical Observatory of Japan

Ya-Wen Tang

Academia Sinica

Kohji Tomisaka

National Astronomical Observatory of Japan

Le Ngoc Tram

Vietnam Academy of Science and Technology

Yusuke Tsukamoto

Kagoshima University

Serena Viti

University College London (UCL)

Hongchi Wang

Chinese Academy of Sciences

Jinjin Xie

Chinese Academy of Sciences

Hsi-Wei Yen

Academia Sinica

Hyunju Yoo

Korea Astronomy and Space Science Institute

Jinghua Yuan

Chinese Academy of Sciences

Hyeong-Sik Yun

Kyung Hee University

Tetsuya Zenko

Kyoto University

Guoyin Zhang

Chinese Academy of Sciences

Chuan-Peng Zhang

Chinese Academy of Sciences

Yapeng Zhang

Chinese University of Hong Kong

Jianjun Zhou

Chinese Academy of Sciences

Lei Zhu

Chinese Academy of Sciences

I. De Looze

University College London (UCL)

C. D. Dowell

Jet Propulsion Laboratory, California Institute of Technology

S. Eyres

University of South Wales

R. Friesen

National Radio Astronomy Observatory

Jean-François Robitaille

Grenoble Alpes University

Sven Van Loo

University of Leeds

Astronomy and Astrophysics

0004-6361 (ISSN) 1432-0746 (eISSN)

Vol. 647 A78

Subject Categories

Astronomy, Astrophysics and Cosmology

Other Physics Topics

Fusion, Plasma and Space Physics

DOI

10.1051/0004-6361/202038624

More information

Latest update

10/25/2022