1. The JCMT BISTRO Survey: Evidence for Pinched Magnetic Fields in Quiescent Filaments of NGC 1333
- Author
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Doi, Yasuo, Tomisaka, Kohji, Hasegawa, Tetsuo, Coudé, Simon, Arzoumanian, Doris, Bastien, Pierre, Matsumura, Masafumi, Tahani, Mehrnoosh, Sadavoy, Sarah, Hull, Charles L. H., Johnstone, Doug, Di Francesco, James, Shimajiri, Yoshito, Furuya, Ray S., Kwon, Jungmi, Tamura, Motohide, Ward-Thompson, Derek, Le Gouellec, Valentin J. M., Hoang, Thiem, Kirchschlager, Florian, Hwang, Jihye, Eswaraiah, Chakali, Koch, Patrick M., Whitworth, Anthony P., Pattle, Kate, Kwon, Woojin, Kang, Jihyun, Inutsuka, Shu-ichiro, Bourke, Tyler L., Tang, Xindi, Fanciullo, Lapo, Lee, Chang Won, Liu, Hong-Li, Lyo, A-Ran, Qiu, Keping, Lai, Shih-Ping, Department of Earth Science and Astronomy, The University of Tokyo (UTokyo), National Astronomical Observatory of Japan (NAOJ), NASA Ames Research Center Cooperative for Research in Earth Science in Technology (ARC-CREST), NASA Ames Research Center (ARC), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Université de Montréal (UdeM), Institut de Recherche sur les Exoplanètes (iREX), Kagawa University [Japan], National Research Council of Canada (NRC), Queen's University [Kingston, Canada], NRC Herzberg Astronomy and Astrophysics, Conseil National de Recherches Canada (CNRC), Tokushima University, Jeremiah Horrocks Institute for Mathematics, Physics and Astronomy [Preston], University of Central Lancashire [Preston] (UCLAN), Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Agence Spatiale Européenne = European Space Agency (ESA), Korea Astronomy and Space Science Institute (KASI), University College of London [London] (UCL), Indian Institute of Science Education and Research Thiruvananthapuram (IISER TVM), Academia Sinica Institute of Astronomy and Astrophysics (ASIAA), Academia Sinica, School of Physics and Astronomy [Cardiff], Cardiff University, Seoul National University [Seoul] (SNU), Nagoya City University [Nagoya, Japan], Jodrell Bank Centre for Astrophysics (JBCA), University of Manchester [Manchester], Xinjiang Astronomical Observatory, Chinese Academy of Sciences [Beijing] (CAS), Yunnan Agricultural University, Nanjing University of Aeronautics and Astronautics [Nanjing] (NUAA), and National Tsing Hua University [Hsinchu] (NTHU)
- Subjects
interstellar medium ,Interstellar filaments (842) ,FOS: Physical sciences ,Astronomy and Astrophysics ,F500 ,Submillimeter astronomy (1647) ,Astrophysics::Cosmology and Extragalactic Astrophysics ,submillimeter astronomy ,Interstellar magnetic fields (845) ,Astrophysics - Astrophysics of Galaxies ,star formation ,interstellar magnetic fields ,Space and Planetary Science ,[SDU]Sciences of the Universe [physics] ,Astrophysics of Galaxies (astro-ph.GA) ,interstellar filaments ,Polarimetry (1278) ,Star formation (1569) ,Interstellar medium (847) ,Astrophysics::Galaxy Astrophysics ,polarimetry - Abstract
We investigate the internal 3D magnetic structure of dense interstellar filaments within NGC 1333 using polarization data at $850 \mu\mathrm{m}$ from the $B$-fields In STar-forming Region Observations survey at the James Clerk Maxwell Telescope. Theoretical models predict that the magnetic field lines in a filament will tend to be dragged radially inward (i.e., pinched) toward the central axis due to the filament's self-gravity. We study the cross-sectional profiles of the total intensity ($I$) and polarized intensity (PI) of dust emission in four segments of filaments unaffected by local star formation that are expected to retain a pristine magnetic field structure. We find that the filaments' FWHM in PI are not the same as those in $I$, with two segments being appreciably narrower in PI (FWHM ratio $\simeq 0.7-0.8$) and one segment being wider (FWHM ratio $\simeq 1.3$). The filament profiles of the polarization fraction ($P$) do not show a minimum at the spine of the filament, which is not in line with an anticorrelation between $P$ and $I$ normally seen in molecular clouds and protostellar cores. Dust grain alignment variation with density cannot reproduce the observed $P$ distribution. We demonstrate numerically that the $I$ and PI cross-sectional profiles of filaments in magnetohydrostatic equilibrium will have differing relative widths depending on the viewing angle. The observed variations of FWHM ratios in NGC 1333 are therefore consistent with models of pinched magnetic field structures inside filaments, and especially if they are magnetically near-critical or supercritical., Comment: Accepted for publication in ApJL
- Published
- 2021