3D CMZ. III. Constraining the 3D Structure of the Central Molecular Zone via Molecular Line Emission and Absorption

The Milky Way’s Central Molecular Zone (CMZ) is the largest concentration of dense molecular gas in the Galaxy, the structure of which is shaped by the complex interplay between Galactic-scale dynamics and extreme physical conditions. Understanding the 3D geometry of this gas is crucial, as it deter...

Full description

Saved in:
Bibliographic Details
Main Authors: Daniel L. Walker, Cara Battersby, Dani Lipman, Mattia C. Sormani, Adam Ginsburg, Simon C. O. Glover, Jonathan D. Henshaw, Steven N. Longmore, Ralf S. Klessen, Katharina Immer, Danya Alboslani, John Bally, Ashley Barnes, H Perry Hatchfield, Elisabeth A. C. Mills, Rowan Smith, Robin G. Tress, Qizhou Zhang
Format: Article
Language:English
Published: IOP Publishing 2025-01-01
Series:The Astrophysical Journal
Subjects:
Online Access:https://doi.org/10.3847/1538-4357/adb5ef
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850193629386113024
author Daniel L. Walker
Cara Battersby
Dani Lipman
Mattia C. Sormani
Adam Ginsburg
Simon C. O. Glover
Jonathan D. Henshaw
Steven N. Longmore
Ralf S. Klessen
Katharina Immer
Danya Alboslani
John Bally
Ashley Barnes
H Perry Hatchfield
Elisabeth A. C. Mills
Rowan Smith
Robin G. Tress
Qizhou Zhang
author_facet Daniel L. Walker
Cara Battersby
Dani Lipman
Mattia C. Sormani
Adam Ginsburg
Simon C. O. Glover
Jonathan D. Henshaw
Steven N. Longmore
Ralf S. Klessen
Katharina Immer
Danya Alboslani
John Bally
Ashley Barnes
H Perry Hatchfield
Elisabeth A. C. Mills
Rowan Smith
Robin G. Tress
Qizhou Zhang
author_sort Daniel L. Walker
collection DOAJ
description The Milky Way’s Central Molecular Zone (CMZ) is the largest concentration of dense molecular gas in the Galaxy, the structure of which is shaped by the complex interplay between Galactic-scale dynamics and extreme physical conditions. Understanding the 3D geometry of this gas is crucial, as it determines the locations of star formation and subsequent feedback. We present a catalog of clouds in the CMZ using Herschel data. Using archival data from the APEX and MOPRA CMZ surveys, we measure averaged kinematic properties of the clouds at 1 and 3 mm. We use archival ATCA data of the H _2 CO (1 _1,0 –1 _1,1 ) 4.8 GHz line to search for absorption towards the clouds, and 4.85 GHz Green Bank Telescope (GBT) C -band data to measure the radio continuum emission. We measure the absorption against the continuum to provide new constraints for the line-of-sight positions of the clouds relative to the Galactic Center, and find a highly asymmetric distribution, with most clouds residing in front of the Galactic Center. The results are compared with different orbital models, and we introduce a revised toy model of a vertically oscillating closed elliptical orbit. We find that most models describe the position–position–velocity structure of the gas reasonably well, but find significant inconsistencies in all cases regarding the near versus far placement of individual clouds. Our results highlight that the CMZ is likely more complex than can be captured by these simple geometric models, along with the need for new data to provide further constraints on the true 3D structure of the CMZ.
format Article
id doaj-art-dbea2813e3f64e9c93c19097a7e89b31
institution OA Journals
issn 1538-4357
language English
publishDate 2025-01-01
publisher IOP Publishing
record_format Article
series The Astrophysical Journal
spelling doaj-art-dbea2813e3f64e9c93c19097a7e89b312025-08-20T02:14:11ZengIOP PublishingThe Astrophysical Journal1538-43572025-01-01984215810.3847/1538-4357/adb5ef3D CMZ. III. Constraining the 3D Structure of the Central Molecular Zone via Molecular Line Emission and AbsorptionDaniel L. Walker0https://orcid.org/0000-0001-7330-8856Cara Battersby1https://orcid.org/0000-0002-6073-9320Dani Lipman2https://orcid.org/0000-0002-5776-9473Mattia C. Sormani3https://orcid.org/0000-0001-6113-6241Adam Ginsburg4https://orcid.org/0000-0001-6431-9633Simon C. O. Glover5https://orcid.org/0000-0001-6708-1317Jonathan D. Henshaw6https://orcid.org/0000-0001-9656-7682Steven N. Longmore7https://orcid.org/0000-0001-6353-0170Ralf S. Klessen8https://orcid.org/0000-0002-0560-3172Katharina Immer9https://orcid.org/0000-0003-4140-5138Danya Alboslani10https://orcid.org/0009-0005-9578-2192John Bally11https://orcid.org/0000-0001-8135-6612Ashley Barnes12https://orcid.org/0000-0003-0410-4504H Perry Hatchfield13https://orcid.org/0000-0003-0946-4365Elisabeth A. C. Mills14https://orcid.org/0000-0001-8782-1992Rowan Smith15https://orcid.org/0000-0002-0820-1814Robin G. Tress16https://orcid.org/0000-0002-9483-7164Qizhou Zhang17https://orcid.org/0000-0003-2384-6589UK ALMA Regional Centre Node, Jodrell Bank Centre for Astrophysics, The University of Manchester , Manchester M13 9PL, UK ; daniel.walker.astro@gmail.com; Department of Physics, University of Connecticut , 196A Auditorium Road, Storrs, CT 06269, USADepartment of Physics, University of Connecticut , 196A Auditorium Road, Storrs, CT 06269, USA; Center for Astrophysics ∣ Harvard & Smithsonian , MS-78, 60 Garden Street, Cambridge, MA 02138, USADepartment of Physics, University of Connecticut , 196A Auditorium Road, Storrs, CT 06269, USAUniversità dell’Insubria , via Valleggio 11, 22100 Como, ItalyUniversity of Florida Department of Astronomy , Bryant Space Science Center, Gainesville, FL, 32611, USAUniversität Heidelberg , Zentrum für Astronomie, Institut für Theoretische Astrophysik, Albert-Ueberle-Str. 2, 69120 Heidelberg, GermanyAstrophysics Research Institute, Liverpool John Moores University , 146 Brownlow Hill, Liverpool L3 5RF, UK; Max-Planck-Institut für Astronomie , Königstuhl 17, D-69117 Heidelberg, GermanyAstrophysics Research Institute, Liverpool John Moores University , 146 Brownlow Hill, Liverpool L3 5RF, UK; Cosmic Origins Of Life (COOL) Research DAO , GermanyCenter for Astrophysics ∣ Harvard & Smithsonian , MS-78, 60 Garden Street, Cambridge, MA 02138, USA; Universität Heidelberg , Zentrum für Astronomie, Institut für Theoretische Astrophysik, Albert-Ueberle-Str. 2, 69120 Heidelberg, Germany; Universität Heidelberg , Interdisziplinäres Zentrum für Wissenschaftliches Rechnen, Im Neuenheimer Feld 225, 69120 Heidelberg, Germany; Radcliffe Institute for Advanced Studies at Harvard University , 10 Garden Street, Cambridge, MA 02138, USAEuropean Southern Observatory (ESO) , Karl-Schwarzschild-Straße 2, 85748 Garching, GermanyDepartment of Physics, University of Connecticut , 196A Auditorium Road, Storrs, CT 06269, USACASA, University of Colorado , 389-UCB, Boulder, CO 80309, USAEuropean Southern Observatory (ESO) , Karl-Schwarzschild-Straße 2, 85748 Garching, GermanyDepartment of Physics, University of Connecticut , 196A Auditorium Road, Storrs, CT 06269, USA; Jet Propulsion Laboratory , California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109, USADepartment of Physics and Astronomy, University of Kansas , 1251 Wescoe Hall Drive, Lawrence, KS 66045, USAScottish Universities Physics Alliance (SUPA) , School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews KY16 9SS, UK; Jodrell Bank Centre for Astrophysics , Department of Physics and Astronomy, University of Manchester, Oxford Road, Manchester M13 9PL, UKInstitute of Physics , Laboratory for Galaxy Evolution and Spectral Modelling, EPFL, Observatoire de Sauverny, Chemin Pegasi 51, 1290 Versoix, SwitzerlandCenter for Astrophysics ∣ Harvard & Smithsonian , MS-78, 60 Garden Street, Cambridge, MA 02138, USAThe Milky Way’s Central Molecular Zone (CMZ) is the largest concentration of dense molecular gas in the Galaxy, the structure of which is shaped by the complex interplay between Galactic-scale dynamics and extreme physical conditions. Understanding the 3D geometry of this gas is crucial, as it determines the locations of star formation and subsequent feedback. We present a catalog of clouds in the CMZ using Herschel data. Using archival data from the APEX and MOPRA CMZ surveys, we measure averaged kinematic properties of the clouds at 1 and 3 mm. We use archival ATCA data of the H _2 CO (1 _1,0 –1 _1,1 ) 4.8 GHz line to search for absorption towards the clouds, and 4.85 GHz Green Bank Telescope (GBT) C -band data to measure the radio continuum emission. We measure the absorption against the continuum to provide new constraints for the line-of-sight positions of the clouds relative to the Galactic Center, and find a highly asymmetric distribution, with most clouds residing in front of the Galactic Center. The results are compared with different orbital models, and we introduce a revised toy model of a vertically oscillating closed elliptical orbit. We find that most models describe the position–position–velocity structure of the gas reasonably well, but find significant inconsistencies in all cases regarding the near versus far placement of individual clouds. Our results highlight that the CMZ is likely more complex than can be captured by these simple geometric models, along with the need for new data to provide further constraints on the true 3D structure of the CMZ.https://doi.org/10.3847/1538-4357/adb5efGalactic centerMolecular clouds
spellingShingle Daniel L. Walker
Cara Battersby
Dani Lipman
Mattia C. Sormani
Adam Ginsburg
Simon C. O. Glover
Jonathan D. Henshaw
Steven N. Longmore
Ralf S. Klessen
Katharina Immer
Danya Alboslani
John Bally
Ashley Barnes
H Perry Hatchfield
Elisabeth A. C. Mills
Rowan Smith
Robin G. Tress
Qizhou Zhang
3D CMZ. III. Constraining the 3D Structure of the Central Molecular Zone via Molecular Line Emission and Absorption
The Astrophysical Journal
Galactic center
Molecular clouds
title 3D CMZ. III. Constraining the 3D Structure of the Central Molecular Zone via Molecular Line Emission and Absorption
title_full 3D CMZ. III. Constraining the 3D Structure of the Central Molecular Zone via Molecular Line Emission and Absorption
title_fullStr 3D CMZ. III. Constraining the 3D Structure of the Central Molecular Zone via Molecular Line Emission and Absorption
title_full_unstemmed 3D CMZ. III. Constraining the 3D Structure of the Central Molecular Zone via Molecular Line Emission and Absorption
title_short 3D CMZ. III. Constraining the 3D Structure of the Central Molecular Zone via Molecular Line Emission and Absorption
title_sort 3d cmz iii constraining the 3d structure of the central molecular zone via molecular line emission and absorption
topic Galactic center
Molecular clouds
url https://doi.org/10.3847/1538-4357/adb5ef
work_keys_str_mv AT daniellwalker 3dcmziiiconstrainingthe3dstructureofthecentralmolecularzoneviamolecularlineemissionandabsorption
AT carabattersby 3dcmziiiconstrainingthe3dstructureofthecentralmolecularzoneviamolecularlineemissionandabsorption
AT danilipman 3dcmziiiconstrainingthe3dstructureofthecentralmolecularzoneviamolecularlineemissionandabsorption
AT mattiacsormani 3dcmziiiconstrainingthe3dstructureofthecentralmolecularzoneviamolecularlineemissionandabsorption
AT adamginsburg 3dcmziiiconstrainingthe3dstructureofthecentralmolecularzoneviamolecularlineemissionandabsorption
AT simoncoglover 3dcmziiiconstrainingthe3dstructureofthecentralmolecularzoneviamolecularlineemissionandabsorption
AT jonathandhenshaw 3dcmziiiconstrainingthe3dstructureofthecentralmolecularzoneviamolecularlineemissionandabsorption
AT stevennlongmore 3dcmziiiconstrainingthe3dstructureofthecentralmolecularzoneviamolecularlineemissionandabsorption
AT ralfsklessen 3dcmziiiconstrainingthe3dstructureofthecentralmolecularzoneviamolecularlineemissionandabsorption
AT katharinaimmer 3dcmziiiconstrainingthe3dstructureofthecentralmolecularzoneviamolecularlineemissionandabsorption
AT danyaalboslani 3dcmziiiconstrainingthe3dstructureofthecentralmolecularzoneviamolecularlineemissionandabsorption
AT johnbally 3dcmziiiconstrainingthe3dstructureofthecentralmolecularzoneviamolecularlineemissionandabsorption
AT ashleybarnes 3dcmziiiconstrainingthe3dstructureofthecentralmolecularzoneviamolecularlineemissionandabsorption
AT hperryhatchfield 3dcmziiiconstrainingthe3dstructureofthecentralmolecularzoneviamolecularlineemissionandabsorption
AT elisabethacmills 3dcmziiiconstrainingthe3dstructureofthecentralmolecularzoneviamolecularlineemissionandabsorption
AT rowansmith 3dcmziiiconstrainingthe3dstructureofthecentralmolecularzoneviamolecularlineemissionandabsorption
AT robingtress 3dcmziiiconstrainingthe3dstructureofthecentralmolecularzoneviamolecularlineemissionandabsorption
AT qizhouzhang 3dcmziiiconstrainingthe3dstructureofthecentralmolecularzoneviamolecularlineemissionandabsorption