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1. 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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2. Radio Galaxy Zoo: Unsupervised Clustering of Convolutionally Auto-encoded Radio-astronomical Images

   https://doi.org/10.1088/1538-3873/ab213d  

   Ralph, Nicholas O.; Norris, Ray P.; Fang, Gu; Park, Laurence A.; Galvin, Timothy J.; Alger, Matthew J.; Andernach, Heinz; Lintott, Chris; Rudnick, Lawrence; Shabala, Stanislav; et al (October 2019, Publications of the Astronomical Society of the Pacific)
3. Radio Galaxy Zoo: Claran – a deep learning classifier for radio morphologies

   https://doi.org/10.1093/mnras/sty2646  

   Wu, Chen; Wong, Oiwei Ivy; Rudnick, Lawrence; Shabala, Stanislav S; Alger, Matthew J; Banfield, Julie K; Ong, Cheng Soon; White, Sarah V; Garon, Avery F; Norris, Ray P; et al (October 2018, Monthly Notices of the Royal Astronomical Society)
4. Radio Galaxy Zoo: observational evidence for environment as the cause of radio source asymmetry

   https://doi.org/10.1093/mnras/sty3070  

   Rodman, P E; Turner, R J; Shabala, S S; Banfield, J K; Wong, O I; Andernach, H; Garon, A F; Kapińska, A D; Norris, R P; Rudnick, L (November 2018, Monthly Notices of the Royal Astronomical Society)
5. A fast radio burst localized to a massive galaxy

   https://doi.org/10.1038/s41586-019-1389-7  

   Ravi, V.; Catha, M.; Addario, L. D; Djorgovski, S. G.; Hallinan, G.; Hobbs, R.; Kocz, J.; Kulkarni, S. R.; Shi, J.; Vedantham, H. K.; et al (August 2019, Nature)

   Intense, millisecond-duration bursts of radio waves (named fast radio bursts) have been detected from beyond the Milky Way. Their dispersion measures—which are greater than would be expected if they had propagated only through the interstellar medium of the Milky Way—indicate extragalactic origins, and imply contributions from the intergalactic medium and perhaps from other galaxies. Although several theories exist regarding the sources of these fast radio bursts, their intensities, durations and temporal structures suggest coherent emission from highly magnetized plasma. Two of these bursts have been observed to repeat, and one repeater (FRB 121102) has been localized to the largest star-forming region of a dwarf galaxy at a cosmological redshift of 0.19. However, the host galaxies and distances of the hitherto non-repeating fast radio bursts are yet to be identified. Unlike repeating sources, these events must be observed with an interferometer that has sufficient spatial resolution for arcsecond localization at the time of discovery. Here we report the localization of a fast radio burst (FRB 190523) to a few-arcsecond region containing a single massive galaxy at a redshift of 0.66. This galaxy is different from the host of FRB 121102, as it is a thousand times more massive, with a specific star-formation rate (the star-formation rate divided by the mass) a hundred times smaller. 

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