Year: 2026
Type: article
Abstract: ABSTRACT Studying samples of young star-forming regions allows us to statistically examine the evolution of their natal gas and dust along with the associated time-scales in the volatile early stages of their lives. With the Physics at High Angular resolution in Nearby GalaxieS survey data, we analyse the diversity of spectral energy distributions (SEDs) for the rich sample of massive star-forming regions found in NGC 1365. By combining unique detections across a variety of data sets from Hubble Space Telescope (HST), James Web Space Telescope (JWST), and Atacama Large Millimeter/sub-millimeter Array (ALMA) images, we produce a catalogue of 85 star-forming regions located in the central starbursting region of NGC 1365. Prior to analysis, we observe clear saturation effects in our four JWST Mid-Infrared Instrument (MIRI) images, and implement a saturation-correction method which allows us to recover data for 23 of 32 saturation-affected regions in these images. We then perform photometry in 13 HST & JWST images which are convolved to match the resolution of MIRI/F2100W ($\sim$64 pc), allowing us to probe star clusters as well as their immediate surroundings. Upon deriving their properties from SED-fitting using Code Investigating GALaxy Emission, we observe that regions selected with progressively redder wavebands are younger and generally more reddened. We also identify three SED features correlated with age: (1) sources with a positive near-infrared slope [(F300W + F360M)/(2$\times$F200W)] are by median half the age of those with negative near-infrared slopes; turnover occurs around 6 Myr, (2) the relative strength of dust emission (F2100W/F200W), and (3) polycyclic aromatic hydrocarbon emission (F335M/F300M) both show that larger such ratios correlate with younger ages. Considering our working resolution, these features are robust to the inclusion of nearby emission surrounding star clusters.
Authors: Stephen Hannon, Eva Schinnerer, Bradley C Whitmore, Hamid Hassani, Daizhong Liu, David A Thilker, Jessica Sutter, Janice C Lee, Jimena Rodriguez, Thomas G Williams, Médéric Boquien, Daniel A Dale, Erik Rosolowsky, Ralf S Klessen, Aida Wofford, Kiana F Henny, Kathryn Grasha, Rémy Indebetouw, Kathryn Kreckel
Institutions: Max Planck Society, Max Planck Institute for Astronomy, Space Telescope Science Institute, University of Alberta, Chinese Academy of Sciences, Purple Mountain Observatory, Johns Hopkins University, Whitman College, University of Arizona, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Astrofísica de La Plata, Universidad Nacional de La Plata, University of Oxford, Centre National de la Recherche Scientifique, Université Côte d'Azur, Lagrange Laboratory, Observatoire de la Côte d’Azur, University of Wyoming, Heidelberg University, University of California San Diego, Universidad Nacional Autónoma de México, Australian National University, ASTRO-3D, ARC Centre of Excellence for All-sky Astrophysics, National Radio Astronomy Observatory, University of Virginia
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $3,046
Funders: Smithsonian Institution, National Aeronautics and Space Administration, California Department of Fish and Game, Entomological Society of America, Communal Studies Association, Space Telescope Science Institute, Australian Government, Deutsche Forschungsgemeinschaft, Agence Nationale de la Recherche, Chinese Academy of Sciences, Universidad Nacional Autónoma de México, Agencia Nacional de Investigación y Desarrollo, University of California, San Diego, Smithsonian Astrophysical Observatory, Australian Research Council, Dirección General de Asuntos del Personal Académico, Universidad Nacional Autónoma de México, Division of Loan Repayment, H2020 European Research Council
Awards: G103270039, G1070520780, G1190173965, G1224374757, G1338664626, G1436661812, G1471022000, G1627648589, G1675634561, G1692958442, G2329447088, G2428672771, G2485251337, G256731684, G2646983214, Stars and Galaxies: The chemical abundance breakthrough, G2828991432, G3714824817, G3889686005, G4097673775, G4247749212, G4518818167, G4704682132, G4707917552, G4724125240, G4783087731, G4962368421, G5197873167, G5568641063, G5583297626, G5787190151, G6032193949, G6270753107, G6273510985, G6461157608, G6526081583, G6685065609, G7098370941, EXC 2181: STRUKTUREN: Emergenz in Natur, Mathematik und komplexen Daten, G767601387, G7843559024, CENTRO DE ASTROFISICA Y TECNOLOGIAS AFINES (CATA), G8800819381, G880779785, G884397560, G8978798575
OpenAlex ID: W7141339857