The PARADIGM project I: a multiscale radio morphological analysis of local U/LIRGS
Artikel i vetenskaplig tidskrift, 2024
Disentangling the radio flux contribution from star formation (SF) and active-galactic-nuclei (AGNs) activity is a long-standing problem in extragalactic astronomy, since at frequencies of 10 GHz, both processes emit synchrotron radiation. We present in this work the general objectives of the PARADIGM (PAnchromatic high-Resolution Analysis of DIstant Galaxy Mergers) project, a multi-instrument concept to explore SF and mass assembly of galaxies. We introduce two novel general approaches for a detailed multiscale study of the radio emission in local (ultra) luminous infrared galaxies (U/LIRGs). In this work, we use archival interferometric data from the Very Large Array (VLA) centred at ∼6 GHz (C band) and present new observations from the e-Multi-Element Radio-Linked Interferometer Network (e-MERLIN) for UGC 5101, VV 705, VV 250, and UGC 8696. Using our image decomposition methods, we robustly disentangle the radio emission into distinct components by combining information from the two interferometric arrays. We use e-MERLIN as a probe of the core-compact radio emission (AGN or starburst) at ∼20 pc scales, and as a probe of nuclear diffuse emission, at scales ∼100-200 pc. With VLA, we characterize the source morphology and the flux density on scales from ∼200 pc up to and above 1 kpc. As a result, we find deconvolved and convolved sizes for nuclear regions from ∼10 to ∼200 pc. At larger scales, we find sizes of 1.5-2 kpc for diffuse structures (with effective sizes of ∼300-400 pc). We demonstrate that the radio emission from nuclear extended structures (∼100 pc) can dominate over core-compact components, providing a significant fraction of the total multiscale SF output. We establish a multiscale radio tracer for SF by combining information from different instruments. Consequently, this work sets a starting point to potentially correct for overestimations of AGN fractions and underestimates of SF activity.
techniques: interferometric
galaxies: star formation
galaxies: starburst
radio continuum: galaxies
techniques: image processing
galaxies: nuclei
Författare
Geferson Lucatelli
University of Manchester
R. J. Beswick
University of Manchester
J. Moldon
Instituto de Astrofisica de Andalucía (IAA)
University of Manchester
M.A. Pérez-Torres
Universidad de Zaragoza
Instituto de Astrofisica de Andalucía (IAA)
European University Cyprus
John Conway
Chalmers, Rymd-, geo- och miljövetenskap, Onsala rymdobservatorium
Antxon Alberdi
Instituto de Astrofisica de Andalucía (IAA)
C. Romero-Cañizales
Academia Sinica
Eskil Varenius
Chalmers, Rymd-, geo- och miljövetenskap, Onsala rymdobservatorium
H. R. Klockner
Max-Planck-Gesellschaft
Loreto Barcos-Munoz
University of Virginia
National Radio Astronomy Observatory
M. Bondi
Istituto di Radioastronomia
Simon T. Garrington
University of Manchester
Susanne Aalto
Chalmers, Rymd-, geo- och miljövetenskap, Astronomi och plasmafysik
Willem A. Baan
Xinjiang Astronomical Observatory
Netherlands Institute for Radio Astronomy (ASTRON)
Y. Pihlstrom
University of New Mexico
National Radio Astronomy Observatory
Monthly Notices of the Royal Astronomical Society
00358711 (ISSN) 13652966 (eISSN)
Vol. 529 4 4468-4499Ämneskategorier
Astronomi, astrofysik och kosmologi
DOI
10.1093/mnras/stae744