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 4468-4499

Ämneskategorier

Astronomi, astrofysik och kosmologi

DOI

10.1093/mnras/stae744

Mer information

Senast uppdaterat

2024-05-21