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arXiv · 2412.17716

A Tale of Three: Magnetic Fields along the Orion Integral-Shaped Filament as Revealed by JCMT BISTRO survey

Abstract

As part of the BISTRO survey, we present JCMT 850 $\mu$m polarimetric observations towards the Orion Integral-Shaped Filament (ISF) that covers three portions known as OMC-1, OMC-2, and OMC-3. The magnetic field threading the ISF seen in the JCMT POL-2 map appears as a tale of three: pinched for OMC-1, twisted for OMC-2, and nearly uniform for OMC-3. A multi-scale analysis shows that the magnetic field structure in OMC-3 is very consistent at all the scales, whereas the field structure in OMC-2 shows no correlation across different scales. In OMC-1, the field retains its mean orientation from large to small scales, but shows some deviations at small scales. Histograms of relative orientations between the magnetic field and filaments reveal a bimodal distribution for OMC-1, a relatively random distribution for OMC-2, and a distribution with a predominant peak at 90$^\circ$ for OMC-3. Furthermore, the magnetic fields in OMC-1 and OMC-3 both appear to be aligned perpendicular to the fibers, which are denser structures within the filament, but the field in OMC-2 is aligned along with the fibers. All these suggest that gravity, turbulence, and magnetic field are each playing a leading role in OMC-1, 2, and 3, respectively. While OMC-2 and 3 have almost the same gas mass, density, and non-thermal velocity dispersion, there are on average younger and fewer young stellar objects in OMC-3, providing evidence that a stronger magnetic field will induce slower and less efficient star formation in molecular clouds.

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Jintai Wu, Keping Qiu, Frederick Poidevin, Pierre Bastien, Junhao Liu, Tao-Chung Ching, Tyler L. Bourke, Derek Ward-Thompson, Kate Pattle, Doug Johnstone, Patrick M. Koch, Doris Arzoumanian, Chang Won Lee, Lapo Fanciullo, Takashi Onaka, Jihye Hwang, Valentin J. M. Le Gouellec, Archana Soam, Motohide Tamura, Mehrnoosh Tahani, Chakali Eswaraiah, Hua-Bai Li, David Berry, Ray S. Furuya, Simon Coude, Woojin Kwon, Sheng-Jun Lin, Jia-Wei Wang, Tetsuo Hasegawa, Shih-Ping Lai, Do-Young Byun, Zhiwei Chen, Huei-Ru Vivien Chen, Wen Ping Chen, Mike Chen, Jungyeon Cho, Youngwoo Choi, Yunhee Choi, Minho Choi, Antonio Chrysostomou, Eun Jung Chung, Sophia Dai, James Di Francesco, Pham Ngoc Diep, Yasuo Doi, Hao-Yuan Duan, Yan 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, Saeko Hayashi, Thiem Hoang, Martin Houde, Tsuyoshi Inoue, Shu-ichiro Inutsuka, Kazunari Iwasaki, Il-Gyo Jeong, Vera Konyves, Ji-hyun Kang, Miju Kang, Janik Karoly, Akimasa Kataoka, Koji Kawabata, Shinyoung Kim, Mi-Ryang Kim, Kyoung Hee Kim, Kee-Tae Kim, Jongsoo Kim, Hyosung Kim, Gwanjeong Kim, Florian Kirchschlager, Jason Kirk, Masato I. N. Kobayashi, Takayoshi Kusune, Jungmi Kwon, Kevin Lacaille, Chi-Yan Law, Hyeseung Lee, Chin-Fei Lee, Sang-Sung Lee, Jeong-Eun Lee, Dalei Li, Di Li, Guangxing Li, Sheng-Yuan Liu, Tie Liu, Hong-Li Liu, Xing Lu, A-Ran Lyo, Steve Mairs. 2024-12-23. A Tale of Three: Magnetic Fields along the Orion Integral-Shaped Filament as Revealed by JCMT BISTRO survey. https://doi.org/10.3847/2041-8213%2Fad93d2

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