_version_ 1866911692518064128
author Zhao, Mengke
Qiu, Keping
Kang, Ji-hyun
Tang, Xindi
Whitworth, Anthony
Ward-Thompson, Derek
Onaka, Takashi
Lee, Chang Won
Bourke, Tyler L.
Hwang, Jihye
Eden, David
Hoang, Thiem
Tamura, Motohide
Kwon, Jungmi
Priestley, Felix
Kim, Kee-Tae
Arzoumanian, Doris
Di Francesco, James
Eswaraiah, Chakali
Johnstone, Doug
Ngoc, Nguyen Bich
Chen, Zhiwei
Sadavoy, Sarah
Soam, Archana
Furuya, Ray S.
Lai, Shih-Ping
Kwon, Woojin
Bastien, Pierre
Pattle, Kate
Berry, David
author_facet Zhao, Mengke
Qiu, Keping
Kang, Ji-hyun
Tang, Xindi
Whitworth, Anthony
Ward-Thompson, Derek
Onaka, Takashi
Lee, Chang Won
Bourke, Tyler L.
Hwang, Jihye
Eden, David
Hoang, Thiem
Tamura, Motohide
Kwon, Jungmi
Priestley, Felix
Kim, Kee-Tae
Arzoumanian, Doris
Di Francesco, James
Eswaraiah, Chakali
Johnstone, Doug
Ngoc, Nguyen Bich
Chen, Zhiwei
Sadavoy, Sarah
Soam, Archana
Furuya, Ray S.
Lai, Shih-Ping
Kwon, Woojin
Bastien, Pierre
Pattle, Kate
Berry, David
contents We present high-resolution magnetic field maps of the M17 SW molecular cloud using JCMT 850 $μ$m dust polarization at a scale of 14$''$. The magnetic field exhibits a distinct arc-like structure that encircles three dense clumps (C1, C2, and C3). By combining polarization data with ammonia line observations, the plane-of-sky magnetic field strength, measured using the Skalidis-Tassis method to minimize angle dispersion errors, ranges from 0.1 to 2.4 mG (mean: 0.54 mG). Energy budget analysis reveals a hierarchy dominated by gravity ($e_G \approx 10^{-7.8}$ erg cm$^{-3}$), which exceeds both magnetic ($e_B \approx 10^{-8.3}$ erg cm$^{-3}$) and turbulent ($e_k \approx 10^{-8.7}$ erg cm$^{-3}$) energies. Since all three energy densities lie within one order of magnitude, gravitational dominance acts primarily as the global driver, while the system remains in a state of near-equipartition. Structurally, the northeastern boundary shows magnetic field lines perpendicular to the shock front, consistent with compression from the adjacent HII region. Within the cloud, magnetic field lines generally align with gravity to assist collapse, but turn perpendicular to gravity within curved accretion bridges. This configuration provides support against radial collapse while guiding gas flow. Kinematic evidence suggests that these channels transport material from Clump C3 onto the massive Clump C2. Star formation in M17 SW is globally driven by gravity but locally regulated by the magnetic field structure.
format Preprint
id arxiv_https___arxiv_org_abs_2605_17708
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle BISTRO Survey: Gravity-Dominated and Magnetically Regulated Star Formation in M17 SW
Zhao, Mengke
Qiu, Keping
Kang, Ji-hyun
Tang, Xindi
Whitworth, Anthony
Ward-Thompson, Derek
Onaka, Takashi
Lee, Chang Won
Bourke, Tyler L.
Hwang, Jihye
Eden, David
Hoang, Thiem
Tamura, Motohide
Kwon, Jungmi
Priestley, Felix
Kim, Kee-Tae
Arzoumanian, Doris
Di Francesco, James
Eswaraiah, Chakali
Johnstone, Doug
Ngoc, Nguyen Bich
Chen, Zhiwei
Sadavoy, Sarah
Soam, Archana
Furuya, Ray S.
Lai, Shih-Ping
Kwon, Woojin
Bastien, Pierre
Pattle, Kate
Berry, David
Astrophysics of Galaxies
We present high-resolution magnetic field maps of the M17 SW molecular cloud using JCMT 850 $μ$m dust polarization at a scale of 14$''$. The magnetic field exhibits a distinct arc-like structure that encircles three dense clumps (C1, C2, and C3). By combining polarization data with ammonia line observations, the plane-of-sky magnetic field strength, measured using the Skalidis-Tassis method to minimize angle dispersion errors, ranges from 0.1 to 2.4 mG (mean: 0.54 mG). Energy budget analysis reveals a hierarchy dominated by gravity ($e_G \approx 10^{-7.8}$ erg cm$^{-3}$), which exceeds both magnetic ($e_B \approx 10^{-8.3}$ erg cm$^{-3}$) and turbulent ($e_k \approx 10^{-8.7}$ erg cm$^{-3}$) energies. Since all three energy densities lie within one order of magnitude, gravitational dominance acts primarily as the global driver, while the system remains in a state of near-equipartition. Structurally, the northeastern boundary shows magnetic field lines perpendicular to the shock front, consistent with compression from the adjacent HII region. Within the cloud, magnetic field lines generally align with gravity to assist collapse, but turn perpendicular to gravity within curved accretion bridges. This configuration provides support against radial collapse while guiding gas flow. Kinematic evidence suggests that these channels transport material from Clump C3 onto the massive Clump C2. Star formation in M17 SW is globally driven by gravity but locally regulated by the magnetic field structure.
title BISTRO Survey: Gravity-Dominated and Magnetically Regulated Star Formation in M17 SW
topic Astrophysics of Galaxies
url https://arxiv.org/abs/2605.17708