ALMA Central molecular zone Exploration Survey (ACES) VI: ALMA Large Program Reveals a Highly Filamentary Central Molecular Zone
Abstract
The Central Molecular Zone (CMZ) of the Milky Way is the way station that primarily controls how much gas flows from the disk of the Galaxy towards the central nucleus. While this region is well documented to have extreme gas properties that clearly distinguish it from the rest of the Galaxy, the properties of the bulk molecular gas at high angular resolution are relatively unexplored. Band 3 data from the ALMA (Atacama Large Millimeter/Submillimeter Array) large program ACES (ALMA CMZ Exploration Survey) reveal the highly filamentary nature of CMZ molecular gas at high resolution (3" or 0.1pc) across the entire CMZ. Visual inspection of these data suggests that there are at least two general classes of elongated structures, which we identify as: i) large-scale (10 pc) filamentary structures (LFs) and ii) a ubiquitous population of small-scale (about 1 pc) filamentary structures (SFs). We present detailed morphological and kinematic properties towards three structures in each category, as well as their association with magnetic fields and the correlation of HNCO 4(0,4)-3(0,3) with other molecular species. Our investigation reveals that these structures are largely coherent in position-position-velocity space. The alignment with the magnetic field structure is mixed, with some parallel, some perpendicular, and some intermediate alignments. We find that LFs likely trace pieces of contiguous CMZ orbital structures and are a manifestation of global CMZ dynamics. The second class, SFs, are pervasive and may be the result of complicated turbulence and shearing dynamics in the CMZ gas flows, as seen in numerical simulations.
Cite
@article{arxiv.2602.20262,
title = {ALMA Central molecular zone Exploration Survey (ACES) VI: ALMA Large Program Reveals a Highly Filamentary Central Molecular Zone},
author = {Cara Battersby and Miriam G. Santa-Maria and Dani Lipman and Dylan M. Paré and Rachel R. Lee and Pablo García and Izaskun Jiménez-Serra and Xing Pan and Daniel L. Walker and Jack Sullivan and Danya Alboslani and H Perry Hatchfield and Yue Hu and Alex Lazarian and Jennifer Wallace and Qizhou Zhang and Xing Lu and Elisabeth A. C. Mills and Adam Ginsburg and Ashley T. Barnes and Pei-Ying Hsieh and Jonathan D. Henshaw and Steven N. Longmore and John Bally and Laura Colzi and Paul T. P. Ho and Maya A. Petkova and Mattia C. Sormani and N. Bijas and Alyssa Bulatek and Natalie O. Butterfield and Christoph Federrath and Simon C. O. Glover and Mark D. Gorski and Savannah R. Gramze and Christian Henkel and Janik Karoly and Ralf S. Klessen and Sergio Martín and Francisco Nogueras-Lara and Jaime E. Pineda and Denise Riquelme-Vásquez and Víctor M. Rivilla and Álvaro Sánchez-Monge and Anika Schmiedeke and Yoshiaki Sofue and Volker Tolls},
journal= {arXiv preprint arXiv:2602.20262},
year = {2026}
}
Comments
Re-submitted to MNRAS after referee report