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   https://doi.org/10.3847/1538-3881/aaff62  

   Garon, Avery F.; Rudnick, Lawrence; Wong, O. Ivy; Jones, Tom W.; Kim, Jin-Ah; Andernach, Heinz; Shabala, Stanislav S.; Kapińska, Anna D.; Norris, Ray P.; de Gasperin, Francesco; et al (March 2019, The Astronomical Journal)
2. Radio Galaxy Zoo: new giant radio galaxies in the RGZ DR1 catalogue

   https://doi.org/10.1093/mnras/staa2805  

   Tang, H; Scaife, A M; Wong, O I; Kapińska, A D; Rudnick, L; Shabala, S S; Seymour, N; Norris, R P (October 2020, Monthly Notices of the Royal Astronomical Society)

   null (Ed.)

   ABSTRACT In this paper, we present the identification of five previously unknown giant radio galaxies (GRGs) using Data Release 1 of the Radio Galaxy Zoo citizen science project and a selection method appropriate to the training and validation of deep learning algorithms for new radio surveys. We associate one of these new GRGs with the brightest cluster galaxy (BCG) in the galaxy cluster GMBCG J251.67741+36.45295 and use literature data to identify a further 13 previously known GRGs as BCG candidates, increasing the number of known BCG GRGs by $$\gt 60$$ per cent. By examining local galaxy number densities for the number of all known BCG GRGs, we suggest that the existence of this growing number implies that GRGs are able to reside in the centres of rich (∼1014 M⊙) galaxy clusters and challenges the hypothesis that GRGs grow to such sizes only in locally underdense environments. 

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3. A Radio Study of Persistent Radio Sources in Nearby Dwarf Galaxies: Implications for Fast Radio Bursts

   https://doi.org/10.3847/1538-4357/ad6568  

   Dong_董, Y_雨欣; Eftekhari, T.; Fong, W.; Bhandari, S.; Berger, E.; Ould-Boukattine, O_S; Hessels, J_W_T; Sridhar, N.; Reines, A.; Margalit, B.; et al (September 2024, The Astrophysical Journal)

   Abstract We present 1–12 GHz Karl G. Jansky Very Large Array observations of nine off-nuclear persistent radio sources (PRSs) in nearby (z≲ 0.055) dwarf galaxies, along with high-resolution European VLBI Network observations for one of them at 1.7 GHz. We explore the plausibility that these PRSs are associated with fast radio burst (FRB) sources by examining their properties—physical sizes, host-normalized offsets, spectral energy distributions (SEDs), radio luminosities, and light curves—and compare them to those of the PRSs associated with FRB 20121102A and FRB 20190520B, two known active galactic nuclei (AGN), and one likely AGN in our sample with comparable data, as well as other radio transients exhibiting characteristics analogous to FRB-PRSs. We identify a single source in our sample, J1136+2643, as the most promising FRB-PRS, based on its compact physical size and host-normalized offset. We further identify two sources, J0019+1507 and J0909+5655, with physical sizes comparable to FRB-PRSs, but which exhibit large offsets and flat spectral indices potentially indicative of a background AGN origin. We test the viability of neutron star wind nebula and hypernebula models for J1136+2643 and find that the physical size, luminosity, and SED of J1136+2643 are broadly consistent with these models. Finally, we discuss the alternative interpretation that the radio sources are instead powered by accreting massive black holes, and we outline future prospects and follow-up observations for differentiating between these scenarios. 

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4. Shocked Narrow-angle Tail Radio Galaxies: Simulations and Emissions

   https://doi.org/10.3847/1538-4357/ab4efa  

   O’Neill, Brian J.; Jones, T. W.; Nolting, Chris; Mendygral, P. J. (December 2019, The Astrophysical Journal)
5. High-resolution VLA low radio frequency observations of the Perseus cluster: radio lobes, mini-halo, and bent-jet radio galaxies

   https://doi.org/10.1093/mnras/staa2003  

   Gendron-Marsolais, M; Hlavacek-Larrondo, J; van Weeren, R J; Rudnick, L; Clarke, T E; Sebastian, B; Mroczkowski, T; Fabian, A C; Blundell, K M; Sheldahl, E; et al (November 2020, Monthly Notices of the Royal Astronomical Society)

   null (Ed.)

   ABSTRACT We present the first high-resolution 230–470 MHz map of the Perseus cluster obtained with the Karl G. Jansky Very Large Array. The high dynamic range and resolution achieved have allowed the identification of previously unknown structures in this nearby galaxy cluster. New hints of sub-structures appear in the inner radio lobes of the brightest cluster galaxy NGC 1275. The spurs of radio emission extending into the outer X-ray cavities, inflated by past nuclear outbursts, are seen for the first time at these frequencies, consistent with spectral aging. Beyond NGC 1275, we also analyse complex radio sources harboured in the cluster. Two new distinct, narrowly collimated jets are visible in IC 310, consistent with a highly projected narrow-angle tail radio galaxy infalling into the cluster. We show how this is in agreement with its blazar-like behaviour, implying that blazars and bent-jet radio galaxies are not mutually exclusive. We report the presence of filamentary structures across the entire tail of NGC 1265, including two new pairs of long filaments in the faintest bent extension of the tail. Such filaments have been seen in other cluster radio sources such as relics and radio lobes, indicating that there may be a fundamental connection between all these radio structures. We resolve the very narrow and straight tail of CR 15 without indication of double jets, so that the interpretation of such head–tail sources is yet unclear. Finally, we note that only the brightest western parts of the mini-halo remain, near NGC 1272 and its bent double jets. 

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