https://doi.org/10.1051/epjconf/202225700002
Probing the role of magnetic fields in star-forming filaments: NIKA2-Pol commissioning results toward OMC-1
1 AIM, CEA, CNRS, Université Paris-Saclay, Université Paris Diderot, Sorbonne Paris Cité, 91191 Gifsur-Yvette, France
2 LLR (Laboratoire Leprince-Ringuet), CNRS, École Polytechnique, Institut Polytechnique de Paris, Palaiseau, France
3 School of Physics and Astronomy, Cardiff University, Queen’s Buildings, The Parade, Cardiff, CF24 3AA, UK
4 Univ. Grenoble Alpes, CNRS, Grenoble INP, LPSC-IN2P3, 53, avenue des Martyrs, 38000 Grenoble, France
5 Institut d’Astrophysique Spatiale (IAS), CNRS, Université Paris Sud, Orsay, France
6 Institut Néel, CNRS, Université Grenoble Alpes, France
7 Institut de RadioAstronomie Millimétrique (IRAM), Grenoble, France
8 Aix Marseille Univ, CNRS, CNES, LAM (Laboratoire d’Astrophysique de Marseille), Marseille, France
9 Dipartimento di Fisica, Sapienza Università di Roma, Piazzale Aldo Moro 5, I-00185 Roma, Italy
10 Univ. Grenoble Alpes, CNRS, IPAG, 38000 Grenoble, France
11 Centro de Astrobiología (CSIC-INTA), Torrejón de Ardoz, 28850 Madrid, Spain
12 Instituto de Radioastronomía Milimétrica (IRAM), Granada, Spain
13 LERMA, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Université, UPMC, 75014 Paris, France
14 School of Earth and Space Exploration and Department of Physics, Arizona State University, Tempe, AZ 85287, USA
15 Laboratoire de Physique de l’École Normale Supérieure, ENS, PSL Research University, CNRS, Sorbonne Université, Université de Paris, 75005 Paris, France
16 Department of Physics and Astronomy, University of Pennsylvania, 209 South 33rd Street, Philadelphia, PA, 19104, USA
17 Institut d’Astrophysique de Paris, CNRS (UMR7095), 98 bis boulevard Arago, 75014 Paris, France
18 Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
19 Caltech, Pasadena, CA 91125, USA
20 National Astronomical Observatory of Japan, National Institutes of Natural Sciences, Osawa, Mitaka, Tokyo 181-8588, Japan
21 Department of Physics and Astronomy, Graduate School of Science and Engineering, Kagoshima University, 1-21-35 Korimoto, Kagoshima, Kagoshima 890-0065, Japan
* e-mail: hamza.ajeddig@cea.fr
Published online: 17 January 2022
Dust polarization observations are a powerful, practical tool to probe the geometry (and to some extent, the strength) of magnetic fields in starforming regions. In particular, Planck polarization data have revealed the importance of magnetic fields on large scales in molecular clouds. However, due to insufficient resolution, Planck observations are unable to constrain the B-field geometry on prestellar and protostellar scales. The high angular resolution of 11.7 arcsec provided by NIKA2-Pol 1.15 mm polarimetric imaging, corresponding to 0.02 pc at the distance of the Orion molecular cloud (OMC), makes it possible to advance our understanding of the B-field morphology in star-forming filaments and dense cores (IRAM 30m large program B-FUN). The commissioning of the NIKA2-Pol instrument has led to several challenging issues, in particular, the instrumental polarization or intensity-to-polarization “leakage” effect. In the present paper, we illustrate how this effect can be corrected for, leading to reliable exploitable data in a structured, extended source such as OMC-1. We present a statistical comparison between NIKA2-Pol and SCUBA2-Pol2 results in the OMC-1 region. We also present tentative evidence of local pinching of the B-field lines near Orion-KL, in the form of a new small-scale hourglass pattern, in addition to the larger-scale hourglass already seen by other instruments such as Pol2.
© The Authors, published by EDP Sciences, 2022
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