Dense gas scaling relations at kiloparsec scales across nearby galaxies with the ALMA ALMOND and IRAM 30 m EMPIRE surveys
Year: 2024
Type: article
Abstract: Dense, cold gas is the key ingredient for star formation. Over the last two decades, HCN(1 − 0) emission has been the most accessible dense gas tracer for studying external galaxies. We present new measurements that demonstrate the relationship between dense gas tracers, bulk molecular gas tracers, and star formation in the ALMA ALMOND survey, the largest sample of resolved (1–2 kpc resolution) HCN maps of galaxies in the local Universe ( d < 25 Mpc). We measured HCN/CO, a line ratio sensitive to the physical density distribution, and the star formation rate to HCN ratio (SFR/HCN), a proxy for the dense gas star formation efficiency, as a function of molecular gas surface density, stellar mass surface density, and dynamical equilibrium pressure across 31 galaxies (a factor of > 3 more compared to the previously largest such study, EMPIRE). HCN/CO increases (slope of ≈0.5 and scatter of ≈0.2 dex) and SFR/HCN decreases (slope of ≈ − 0.6 and scatter of ≈0.4 dex) with increasing molecular gas surface density, stellar mass surface density, and pressure. Galaxy centres with high stellar mass surface densities show a factor of a few higher HCN/CO and lower SFR/HCN compared to the disc average, but the two environments follow the same average trend. Our results emphasise that molecular gas properties vary systematically with the galactic environment and demonstrate that the scatter in the Gao–Solomon relation (SFR/HCN) has a physical origin.
Source: Astronomy and Astrophysics
Authors: Lukas Neumann, María J. Jiménez-Donaire, Adam K. Leroy, Frank Bigiel, Antonio Usero, Jiayi Sun, Eva Schinnerer, Miguel Querejeta, Sophia K. Stuber, Ivana Bešlić, Ashley Barnes, Jakob den Brok, Yixian Cao, Cosima Eibensteiner, Hao He, Ralf S. Klessen, Fu-Heng Liang, Daizhong Liu, Hsi-An Pan, Thomas G. Williams
Institutions: European Southern Observatory, University of Bonn, European Southern Observatory, Yebes Observatory, Instituto Geográfico Nacional, The Ohio State University, Princeton University, Max Planck Institute for Astronomy, Centre National de la Recherche Scientifique, Université Paris Sciences et Lettres, Observatoire de Paris, Laboratoire d’Etudes du Rayonnement et de la Matière en Astrophysique et Atmosphères, Center for Astrophysics Harvard & Smithsonian, Max Planck Institute for Extraterrestrial Physics, National Radio Astronomy Observatory, Harvard University, Heidelberg University, Chinese Academy of Sciences, Purple Mountain Observatory, Tamkang University, University of Oxford
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,732
Funders: National Science and Technology Council, National Science Foundation, National Aeronautics and Space Administration, Alexander von Humboldt-Stiftung, California Institute of Technology, National Radio Astronomy Observatory, National Research Foundation, Deutsche Forschungsgemeinschaft, National Science Council, Centre National d’Etudes Spatiales, Korea Astronomy and Space Science Institute, Ministry of Science and Technology, Taiwan, National Astronomical Observatory of Japan, National Science and Technology Council, Jet Propulsion Laboratory, University of California, Los Angeles, European Research Council, National Institutes of Natural Sciences, European Regional Development Fund, Agencia Estatal de Investigación, HORIZON EUROPE European Research Council
Awards: G1622782223, G1675634561, G2262748287, Tracking galaxy evolution with precise and accurate metal abundances in the interstellar medium, G3192712653, G336231339, G3480869486, G3780464728, G4244235011, G425668148, G451917667, G5121615476, G516168872, CAREER: Observing the Physics of Star Formation in Galaxies, G5893977402, G5967599077, G5990384444, G6018591478, G6526081583, G6731467812, G7084143925, EXC 2181: STRUKTUREN: Emergenz in Natur, Mathematik und komplexen Daten, Same, Same But Different: Characterize the Diversity of Star Formation in Nearby Galaxies, G7781737866, G7995740431, Untersuchung der Emission molekularer Linien in der Milchstrasse: das massive Sternentstehungsgebiet W49 im extragalaktischen Kontext, G8684520763, Collaborative Research: Charting the Supernova-Gas-Stars Connection via a Major New VLA Survey of the Local Group
OpenAlex ID: W4405753704