JWST Observations of Starbursts: The Motion of Dust—PAH Kinematics of M82 and NGC 253 with JWST/MIRI Spectroscopy
Year: 2026
Type: article
Abstract: We present an analysis of dust kinematics in the local starburst galaxies M82 (NGC 3034) and NGC 253 using polycyclic aromatic hydrocarbon (PAH) features observed with JWST/MIRI spectroscopy. We are able to produce high-quality velocity maps of the 5.2, 6.2, and 11.3 μ m PAH features, as well as numerous lines of molecular gas via H 2 rotational transitions and ionized gas from [Ne ii ] and H recombination lines. Given the field of view and inclination, we trace a rotating disk in M82 where we observe a steep rise in the velocities followed by flattening, typical of galaxy rotation curves. In NGC 253, however, the 6.2 and 11.3 μ m PAH features trace the launching region of the outflow, firmly within the starburst region. We find the ionized gas also shows outflow contributions in NGC 253 while the warm molecular gas is dominated by rotation. Additionally, the molecular gas outflow velocities are lower than the ionized gas, with the 11.3 μ m PAH feature consistent with the ionized gas rather than the molecular gas. We therefore suggest that PAHs are more closely associated with the ionized gas rather than the molecular at the base of the galaxy outflow, whereas larger-scale imaging shows comparable morphology between PAHs and H I . The 6.2 μ m PAH feature has an even higher outflow velocity for both galaxies, possibly suggesting preferential ionization of the PAHs within the faster-moving hot phase of the base of the outflow.
Source: The Astronomical Journal
Authors: Fergus R. Donnan, Karin Sandstrom, Alberto D. Bolatto, Bruce T. Draine, Sara E. Duval, Ralf S. Klessen, Elisabeth A. C. Mills, Helena M. Richie, J. D. T. Smith, Sylvain Veilleux, Patricia A. Arens, Leindert A. Boogaard, Serena A. Cronin, Daniel A. Dale, Kimberly L. Emig, Rodrigo Herrera-Camus, Thomas S.-Y. Lai, Sebastian Lopez, Laura Lenkić, Rebecca C. Levy, Divakara Mayya, David S. Meier, Kaitlyn E. Sheriff, Utsav Siwakoti, Evan Skillman, Elizabeth Tarantino, Yu-Hsuan Teng, Vicente Villanueva, Fabian Walter, Paul P. van der Werf
Institutions: University of California San Diego, University of Maryland, College Park, Princeton University, University of Toledo, Heidelberg University, University of Kansas, University of Pittsburgh, Swinburne University of Technology, Leiden University, University of Wyoming, National Radio Astronomy Observatory, University of Concepción, Max Planck Institute for Extraterrestrial Physics, California Institute of Technology, Arizona State University, Space Telescope Science Institute, New Mexico Institute of Mining and Technology, University of Minnesota, Max Planck Institute for Astronomy
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $4,499
Funders: National Science Foundation, National Aeronautics and Space Administration, Space Telescope Science Institute, Deutsche Forschungsgemeinschaft, Agence Nationale de la Recherche, Nederlandse Organisatie voor Wetenschappelijk Onderzoek, Max-Planck-Gesellschaft, Universidad de Concepción, Agencia Nacional de Investigación y Desarrollo
Awards: G103270039, G1365422496, G1675634561, G1886942005, CAREER: RACING -- Resolving the Activity Cycle In the Nearest Galaxies, G256731684, G4538171546, Collaborative Research: ACES Galactic Center Mass Flow, G5568641063, G6526081583, G6965168072, EXC 2181: STRUKTUREN: Emergenz in Natur, Mathematik und komplexen Daten, CENTRO DE ASTROFISICA Y TECNOLOGIAS AFINES (CATA), Fuel Up: How Cold Gas Fuels Star Formation Through Cosmic Time
OpenAlex ID: W7214086667