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Title: Magnetic Field Alignment Relative to Multiple Tracers in the High-mass Star-forming Region RCW 36
Abstract

We use polarization data from SOFIA HAWC+ to investigate the interplay between magnetic fields and stellar feedback in altering gas dynamics within the high-mass star-forming region RCW 36, located in Vela C. This region is of particular interest as it has a bipolar Hiiregion powered by a massive star cluster, which may be impacting the surrounding magnetic field. To determine if this is the case, we apply the histogram of relative orientations (HRO) method to quantify the relative alignment between the inferred magnetic field and elongated structures observed in several data sets such as dust emission, column density, temperature, and spectral line intensity maps. The HRO results indicate a bimodal alignment trend, where structures observed with dense gas tracers show a statistically significant preference for perpendicular alignment relative to the magnetic field, while structures probed by the photodissociation region (PDR) tracers tend to align preferentially parallel relative to the magnetic field. Moreover, the dense gas and PDR associated structures are found to be kinematically distinct such that a bimodal alignment trend is also observed as a function of line-of-sight velocity. This suggests that the magnetic field may have been dynamically important and set a preferred direction of gas flow at the time that RCW 36 formed, resulting in a dense ridge developing perpendicular to the magnetic field. However, on filament scales near the PDR region, feedback may be energetically dominating the magnetic field, warping its geometry and the associated flux-frozen gas structures, causing the observed preference for parallel relative alignment.

 
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Award ID(s):
2309542 2009842
PAR ID:
10555483
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
The Astrophysical Journal, Volume 975, Issue 2, id.267, 35 pp.
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
975
Issue:
2
ISSN:
0004-637X
Page Range / eLocation ID:
267
Subject(s) / Keyword(s):
Star formation Star forming regions Interstellar medium Interstellar magnetic fields H II regions Photodissociation regions Molecular clouds 1569 1565 847 845 694 1223 1072 Astrophysics - Astrophysics of Galaxies Astrophysics - Solar and Stellar Astrophysics
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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