A spatially resolved spectral analysis of giant radio galaxies with MeerKAT
ABSTRACT In this study we report the spatially resolved, wideband spectral properties of three giant radio galaxies (GRGs) in the COSMOS field: MGTC J095959.63+024608.6, MGTC J100016.84+015133.0, and MGTC J100022.85+031520.4. One of these galaxies, MGTC J100022.85+031520.4, is reported here for the first time, with a projected linear size of 1.29 Mpc at a redshift of 0.1034. Unlike the other two, it is associated with a brightest cluster galaxy (BCG), making it one of the few GRGs known to inhabit cluster environments. We examine the spectral age distributions of the three GRGs using new MeerKAT UHF-band (544–1088 MHz) observations, and L-band (900–1670 MHz) data from the MeerKAT International GHz Tiered Extragalactic Exploration (MIGHTEE) survey. We test two models of spectral ageing, the Jaffe–Perola and Tribble models, using the Broadband Radio Astronomy Tools (brats) software, and find that they agree well with each other. We estimate the Tribble spectral age for MGTC J095959.63+024608.6 as 68 Myr, for MGTC J100016.84+015133.0 as 47 Myr, and for MGTC J100022.85+031520.4 as 67 Myr. We find significant disagreements between these spectral age estimates and the estimates of the dynamical ages of these GRGs, modelled in cluster and group environments. Our results highlight the need for additional processes that are not accounted for in either the dynamic age or the spectral age estimations.
Authors
- L. Marchetti (ORCID: https://orcid.org/0000-0003-3948-7621)
- L. K. Morabito (ORCID: https://orcid.org/0000-0003-0487-6651)
- Ian Heywood (ORCID: https://orcid.org/0000-0001-6864-5057)
- Zara Randriamanakoto (ORCID: https://orcid.org/0000-0003-2666-4158)
- J. Delhaize (ORCID: https://orcid.org/0000-0002-6149-0846)
- S. V. White (ORCID: https://orcid.org/0000-0002-2340-8303)
- Kate Charlton (ORCID: https://orcid.org/0000-0002-2925-2047)
- M. J. Hardcastle (ORCID: https://orcid.org/0000-0003-4223-1117)
- Catherine Hale (ORCID: https://orcid.org/0000-0001-6279-4772)
- A. R. Taylor (ORCID: https://orcid.org/0000-0001-9885-0676)
- M. J. Jarvis (ORCID: https://orcid.org/0000-0001-7039-9078)
- Kshitij Thorat (ORCID: https://orcid.org/0000-0002-4760-080X)
- M. Brüggen (ORCID: https://orcid.org/0000-0002-3369-7735)
- I. H. Whittam (ORCID: https://orcid.org/0000-0003-2265-5983)
- I. Delvecchio (ORCID: https://orcid.org/0000-0001-8706-2252)
- F. F. An (ORCID: https://orcid.org/0000-0002-3675-5670)
Institutions
- University of Antananarivo (MG)
- University of Hertfordshire (GB)
- University of Cape Town (ZA)
- Universität Hamburg (DE)
- Durham University (GB)
- Rhodes University (ZA)
- Purple Mountain Observatory (CN)
- University of Oxford (GB)
- Istituto di Radioastronomia di Bologna (IT)
- South African Radio Astronomy Observatory (ZA)
- Astronomical Observatory (RS)
- Inter-university Institute for Data Intensive Astronomy (ZA)
- University of Pretoria (ZA)
- University of the Western Cape (ZA)
Publication Details
- Journal
- Monthly Notices of the Royal Astronomical Society
- Published
- 2024-11-28
- DOI
- https://doi.org/10.1093/mnras/stae2543
- Citations
- 2
- Primary Topic
- Galaxies: Formation, Evolution, Phenomena
- Type
- article
- Field-Weighted Citation Impact
- 0.66
Funders
- National Science Foundation
- U.S. Department of Energy
- Yale University
- Vanderbilt University
- New York University
- Princeton University
- Ohio State University
- Harvard University
- University of Florida
- University of Utah
- University of Washington
- Johns Hopkins University
- University of Arizona
- Carnegie Mellon University
- Pennsylvania State University
- University of Virginia
- University of Portsmouth
- New Mexico State University
- Ukrainian Research Institute, Harvard University
- UK Research and Innovation
- European Commission
- National Research Foundation
- University of Pretoria
- Ministry of Education, Culture, Sports, Science and Technology
- National Natural Science Foundation of China
- Academia Sinica
- Catholic University of Pusan
- Cabinet Office, Government of Japan
- Government of Jiangsu Province
- University of the Western Cape
- Universiteit Stellenbosch
- Cape Peninsula University of Technology
- Natural Science Foundation of Jiangsu Province
- University of Tokyo
- National Astronomical Observatory of Japan
- High Energy Accelerator Research Organization
- University of Cape Town
- Max-Planck-Institut für Astrophysik
- Toray Science Foundation
- Office of Science
- College of Engineering, Michigan State University
- National Science Foundation, United Arab Emirates
- Science and Technology Facilities Council
- Japan Society for the Promotion of Science
- Japan Science and Technology Agency
- Brookhaven National Laboratory
- Lawrence Berkeley National Laboratory
- H2020 European Research Council