Year: 2026
Type: preprint
Abstract: The extreme kinematics of the Milky Way's Central Molecular Zone (CMZ) are influenced by processes such as dynamical shearing, cloud collisions, and stellar feedback. These events are visible in molecular data as vertically spiked features in position-velocity (PV) diagrams referred to as high velocity dispersion compact clouds (HVCCs). Using ALMA CMZ Exploration Survey (ACES) CS (2-1) molecular data, we identify a total of 235 HVCC candidates, 163 of which are visually identified, and an additional 72 identified via automated dendrogram methods. For each HVCC we catalog and report the physical and kinematic properties, explore line ratios of the cold dense gas tracer \HNCO with C-shock tracers, classify the morphology of their PV diagrams, and view their position-position-velocity distribution. The sample includes structures which are compact (d<5 pc) and have large velocity extents (20 km/s $<Δ\mathrm{V} <$ 140 km/s), with most structures showing thin, `spiked' PV morphologies. We highlight areas of high ratios between HNCO and C-shock tracers along the edge of known orbital streams, implying a buildup of bar lane gas accreting onto the CMZ. We also find a collection of HVCCs overlapping with the 50 km/s cloud and known circumnuclear disk features. This catalog will be used for future investigation of nuclear inflow and determining dominant mechanisms disrupting average CMZ gas flows.
Source: arXiv (Cornell University)
Authors: Lipman, Dani R., Poznanski, Jakub, Gramze, Savannah R., Cook, Claire E., Battersby, Cara, Wallace, Jennifer, García, Pablo, Adams, Samantha, Mai, Xinyu, Smith, Kai, Butterfield, Natalie, Kempe, Sophia, Ginsburg, Adam, Buddhacharya, Rojita, Oka, Tomoharu, Alboslani, Danya, Armijos-Abendaño, Jairo, Bally, John, Barnes, Ashley T., Budaiev, Nazar, Bulatek, Alyssa, Colzi, Laura, Federrath, Christoph, Feng, Zi-Xuan, Henshaw, Jonathan D., Ho, Paul, Hsieh, Pei-Ying, Immer, Katharina, Jiménez-Serra, Izaskun, Klessen, Ralf S., Longmore, Steven N., Lu, Xing, Mills, Elisabeth A. C., Bijas, N., Nogueras-Lara, Francisco, Paré, Dylan M., Petkova, Maya A., Pineda, Jaime E., Pound, Marc W., Rivilla, Víctor M., Sánchez-Monge, Álvaro, Santa-Maria, Miriam G., Schmiedeke, Anika, Sofue, Yoshiaki, Sormani, Mattia C., Smith, Howard A., Tress, Robin G., Walker, Daniel, Zhang, Qizhou
Institutions: University of Connecticut, University of Florida, University of Kansas, Chinese Academy of Sciences, Universidad Católica del Norte, National Astronomical Observatories, National Radio Astronomy Observatory, Center for Astrophysics Harvard & Smithsonian, Liverpool John Moores University, Keio University, National Polytechnic School, University of Colorado Boulder, University of Colorado System, European Southern Observatory, Haverford College, Centro de Astrobiología, Australian National University, University of Insubria, Heidelberg University, Max Planck Institute for Astronomy, Institute of Astronomy and Astrophysics, Academia Sinica, East Asian Observatory, Academia Sinica, National Astronomical Observatory of Japan, Shanghai Astronomical Observatory, University of Manchester, Consejo Superior de Investigaciones Científicas, Atacama Large Millimeter Submillimeter Array, Max Planck Institute for Extraterrestrial Physics, Institut d'Estudis Espacials de Catalunya, Instituto de Astrofísica de Andalucía, Chalmers University of Technology, University of Maryland, College Park, The University of Tokyo, École Polytechnique Fédérale de Lausanne
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Funders: National Science Foundation, National Aeronautics and Space Administration, Ministerio de Ciencia, Innovación y Universidades, National Radio Astronomy Observatory, Chinese Academy of Sciences South America Center for Astronomy, European Commission, Deutscher Akademischer Austauschdienst, Deutsche Forschungsgemeinschaft, Agence Nationale de la Recherche, Chinese Academy of Sciences, Fondazione Cariplo, Korea Astronomy and Space Science Institute, National Astronomical Observatory of Japan, Consejo Superior de Investigaciones Científicas, National Institutes of Natural Sciences, European Regional Development Fund, Agencia Estatal de Investigación, National Astronomical Observatories, Chinese Academy of Sciences, European Social Fund, HORIZON EUROPE European Research Council
Awards: G10949448, G1105844351, G1175115578, G1204847676, G1255325603, G1272900390, G1348953298, G1507096846, G159187477, G1622782223, G1675634561, G1743472294, G1864822484, G1886942005, G2030784793, G205929289, G210041235, G2262748287, The Milky Way as key to understanding the inward transport of matter to the centre of galaxies, G2340603345, G2469010403, G2542020899, G2550080368, G2551911579, G2601397997, G2650114919, G2756433129, G277576399, G2779896429, Collaborative Research: ACES Galactic Center Mass Flow, G2875128019, G2879720576, G294895050, G300979063, G302750986, Uncovering the Seeds of Star Clusters across the Galaxy, G34346518, 3-D CMZ: Unveiling the Structure of the Center of the Milky Way Galaxy, G3480869486, G3681454997, G3696727022, G3702198118, G3715634343, G373897614, G3803561910, G3817602061, G4042783231, G410571670, G4212894969, G425668148, G4390319345, G4408147216, G451917667, G4526231891, G463062595, G464105488, G491712853, Collaborative Research: ACES Galactic Center Mass Flow, G5080475149, G5099673792, G5178665745, G5195188938, G5380678141, G5404395142, G546199279, G5539308778, G5542129504, CAREER: Shining STARs Amidst the Turbulence, G5635532810, G5881647929, G5894067328, G593054264, CAREER: Mass Measurements in the Galaxy, G5955501538, G5967599077, G6033112984, G6080697404, G617610489, G6218905885, G624666630, G624877701, G6326031618, G6465668149, G6526081583, G6543039948, G6671297155, G6874468849, G6965168072, G6996428894, G7084143925, G7097722406, EXC 2181: STRUKTUREN: Emergenz in Natur, Mathematik und komplexen Daten, G717256432, G7387325513, G7395345766, G7430849242, G7457237104, G7731791180, G7805626310, G7863371703, G7915813472, G8257951253, G8284171658, G8497050386, G8510625649, G855041801, G8667377315, G8709270594, G8829154781, G8888022036, G929308097
OpenAlex ID: W7212142580