B-fields in Star-forming Region Observations (BISTRO): Magnetic Fields in the Filamentary Structures of Serpens Main

Woojin Kwon , Kate Pattle , Sarah Sadavoy , Charles L. H. Hull , Doug Johnstone , Derek Ward-Thompson , James Di Francesco , Patrick M. Koch , Ray Furuya , Yasuo Doi , Valentin J. M. Le Gouellec , Jihye Hwang , A. -Ran Lyo , Archana Soam , Xindi Tang , Thiem Hoang , Florian Kirchschlager , Chakali Eswaraiah , Lapo Fanciullo , Kyoung Hee Kim , Takashi Onaka , Vera Könyves , Ji-Hyun Kang , Chang Won Lee , Motohide Tamura , Pierre Bastien , Tetsuo Hasegawa , Shih-Ping Lai , Keping Qiu , David Berry , Doris Arzoumanian (1) , Tyler L. Bourke , Do-Young Byun , Wen Ping Chen , Huei-Ru Vivien Chen , Mike Chen , Zhiwei Chen , Tao-Chung Ching , Jungyeon Cho , Yunhee Choi , Minho Choi , Antonio Chrysostomou , Eun Jung Chung , Simon Coudé , Sophia Dai , Pham Ngoc Diep , Yan Duan , Hao-Yuan Duan , David Eden , Jason Fiege , Laura M. Fissel , Erica Franzmann , Per Friberg , Rachel Friesen , Gary Fuller , Tim Gledhill , Sarah Graves , Jane Greaves , Matt Griffin , Qilao Gu , Ilseung Han , Jennifer Hatchell , Saeko Hayashi , Martin Houde , Tsuyoshi Inoue , Shu-Ichiro Inutsuka , Kazunari Iwasaki , Il-Gyo Jeong , Miju Kang , Janik Karoly , Akimasa Kataoka , Koji Kawabata , Francisca Kemper , Kee-Tae Kim , Gwanjeong Kim , Mi-Ryang Kim , Shinyoung Kim , Jongsoo Kim , Jason Kirk , Masato I. N. Kobayashi , Takayoshi Kusune , Jungmi Kwon , Kevin Lacaille , Chi-Yan Law , Chin-Fei Lee , Yong-Hee Lee , Hyeseung Lee , Jeong-Eun Lee , Sang-Sung Lee , Dalei Li , Di Li , Hua-Bai Li , Sheng-Jun Lin , Sheng-Yuan Liu , Hong-Li Liu , Junhao Liu , Tie Liu , Xing Lu , Steve Mairs , Masafumi Matsumura , Brenda Matthews , Gerald Moriarty-Schieven , Tetsuya Nagata , Fumitaka Nakamura , Hiroyuki Nakanishi , Nguyen Bich Ngoc , Nagayoshi Ohashi , Geumsook Park , Harriet Parsons , Nicolas Peretto , Felix Priestley , Tae-Soo Pyo , Lei Qian , Ramprasad Rao , Jonathan Rawlings , Mark G. Rawlings , Brendan Retter , John Richer , Andrew Rigby , Hiro Saito , Giorgio Savini , Masumichi Seta , Yoshito Shimajiri , Hiroko Shinnaga , Mehrnoosh Tahani , Ya-Wen Tang , Kohji Tomisaka , Le Ngoc Tram , Yusuke Tsukamoto , Serena Viti , Hongchi Wang , Jia-Wei Wang , Anthony Whitworth , Jintai Wu , Jinjin Xie , Hsi-Wei Yen , Hyunju Yoo , Jinghua Yuan , Hyeong-Sik Yun , Tetsuya Zenko , Yapeng Zhang , Chuan-Peng Zhang , Guoyin Zhang , Jianjun Zhou , Lei Zhu , Ilse De Looze , Philippe André , C. Darren Dowell , Stewart Eyres , Sam Falle , Jean-François Robitaille (2) , Sven Van Loo

1 LAM - Laboratoire d'Astrophysique de Marseille
2 IPAG - Institut de Planétologie et d'Astrophysique de Grenoble

We present 850 μm polarimetric observations toward the Serpens Main molecular cloud obtained using the POL-2 polarimeter on the James Clerk Maxwell Telescope as part of the B-fields In STar-forming Region Observations survey. These observations probe the magnetic field morphology of the Serpens Main molecular cloud on about 6000 au scales, which consists of cores and six filaments with different physical properties such as density and star formation activity. Using the histogram of relative orientation (HRO) technique, we find that magnetic fields are parallel to filaments in less-dense filamentary structures where ${N}_{{{\rm{H}}}_{2}} 0.93\times {10}^{22}$ cm^-2 (magnetic fields perpendicular to density gradients), while they are perpendicular to filaments (magnetic fields parallel to density gradients) in dense filamentary structures with star formation activity. Moreover, applying the HRO technique to denser core regions, we find that magnetic field orientations change to become perpendicular to density gradients again at ${N}_{{{\rm{H}}}_{2}}\approx 4.6\times {10}^{22}$ cm^-2. This can be interpreted as a signature of core formation. At ${N}_{{{\rm{H}}}_{2}}\approx 16\times {10}^{22}$ cm^-2, magnetic fields change back to being parallel to density gradients once again, which can be understood to be due to magnetic fields being dragged in by infalling material. In addition, we estimate the magnetic field strengths of the filaments (B _POS = 60-300 μG)) using the Davis-Chandrasekhar-Fermi method and discuss whether the filaments are gravitationally unstable based on magnetic field and turbulence energy densities.

Keywords: 1278; 845; 1072; 1647; 847; 842; Astrophysics - Astrophysics of Galaxies; Astrophysics - Solar and Stellar Astrophysics

Domains: Sciences of the Universe [physics]; Astrophysics [astro-ph]

Woojin Kwon, Kate Pattle, Sarah Sadavoy, Charles L. H. Hull, Doug Johnstone, et al.. B-fields in Star-forming Region Observations (BISTRO): Magnetic Fields in the Filamentary Structures of Serpens Main. The Astrophysical Journal, 2022, 926, ⟨10.3847/1538-4357/ac4bbe⟩. ⟨insu-03667469⟩