[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"doc-detail-123568-en":3,"doc-seo-123568-105":30,"detail-sidebar-cat-0-en-105":91},{"code":4,"msg":5,"data":6},0,"success",{"doc_id":7,"user_id":8,"nickname":9,"user_avatar":10,"doc_module":4,"category_id":11,"category_name":12,"doc_title":13,"doc_description":14,"doc_content":15,"file_id":16,"file_url":17,"file_type":18,"file_size":19,"view_count":4,"is_deleted":4,"is_public":20,"is_downloadable":20,"audit_status":20,"page_count":21,"language":22,"language_code":23,"site_id":24,"html_lang":23,"table_of_contents":25,"faqs":26,"seo_title":27,"seo_description":14,"update_tm":28,"read_time":29},123568,1099513958607,"Jiven","https://ap-avatar.wpscdn.com/avatar/100002390cf8733938c?x-image-process=image/resize,m_fixed,w_180,h_180&k=1778829742770036399",8,"Research & Report","A Unique, Ring-like Radio Source with Quadrilateral Structure Detected with Machine Learning - Accepted Manuscript","Discovery of a distinctive ring-like radio source in the MeerKAT Galaxy Cluster Legacy Survey (MGCLS) is achieved using a machine learning anomaly detection method. The object lies about 300 arcsec from the MGCLS field center near Abell 209 and resists explanation by simple physical models. Assuming a host galaxy at redshift 0.55, its luminosity (~10^25 W/Hz) matches powerful radio galaxies. Morphology includes a ~175 kpc emission ring, quadrilateral bright regions resembling radio jets, two “ears” separated by 368 kpc, and a diffuse envelope, all with steep spectra (-1.0 to -1.5). High polarization (~25%) persists except at bright patches. Comparisons to ASKAP’s Odd Radio Circles motivate tested models such as starburst termination shocks, end-on radio galaxies, and supermassive black hole mergers, with no single model providing a straightforward fit. The study highlights unsupervised learning for efficiently mining large astronomical datasets.","arXiv :2211 .02062v1 [ astro-ph .GA] 3 Nov 2022  \nA unique, ring-like radio source with quadrilateral structure detected with machine learning  \nM. Lochner, 1,2★ L. Rudnick,3 I. Heywood,4,5,2 K. Knowles5,2 and S. S. Shabala6  \n1 Department of Physics and Astronomy, University of the Western Cape, Bellville, Cape Town, 7535, South Africa  \n2 South African Radio Astronomy Observatory, 2 Fir Street, Black River Park, Observatory, 7925, South Africa  \n3 Minnesota Institute for Astrophysics, University of Minnesota, 116 Church St SE, Minneapolis, MN 55455, USA  \n4 Astrophysics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH, UK  \n5 Centre for Radio Astronomy Techniques and Technologies, Department of Physics and Electronics, Rhodes University, PO Box 94, Makhanda 6140, South Africa  \n6 School of Natural Sciences, Private Bag 37, University of Tasmania, Hobart, TAS 7001, Australia  \nAccepted XXX. Received YYY; in original form ZZZ  \nABSTRACT  \nWe report the discovery of a unique object in the MeerKAT Galaxy Cluster Legacy Survey (MGCLS) using a machine learning anomaly detection algorithm. This strange, ring-like source is 300 from the MGCLS field centred on Abell 209, and is not readily explained by simple physical models. With an assumed host galaxy at a redshift 0 .55, the luminosity (1025 W/Hz) is comparable to powerful radio galaxies. The source consists of a ring of emission 175 kpc across, quadrilateral enhanced brightness regions bearing resemblance to radio jets, two “ears” separated by 368 kpc, and a diffuse envelope. All of the structures appear spectrally steep, ranging from-1.0 to-1.5. The ring has high polarization (25%) except on the bright patches ( \u003C 10%) . We compare this source to the Odd Radio Circles recently discovered in ASKAP data and discuss several possible physical models, including a termination shock from starburst activity, an end-on radio galaxy, and a supermassive black hole merger event. No simple model can easily explain the observed structure of the source. This work, as well as other recent discoveries, demonstrates the power of unsupervised machine learning in mining large datasets for scientifically interesting sources.  \nKey words: galaxies:active – radio continuum:galaxies  \n1 INTRODUCTION  \nOver a billion radio sources are expected to be catalogued by surveys with the Square Kilometre Array (SKA, Braun et al. 2015). Already, the SKA precursor telescopes, such as MeerKAT (Jonas & MeerKAT Team 2016), ASKAP (Hotan et al. 2021) and LOFAR (van Haarlem et al. 2013), are producing datasets of remarkable size and richness. These datasets have proven to be a treasure trove for scientific discoveries, including Odd Radio Circles (ORCs Norris et al. 2021), the“heartworm”nebula (Cotton et al. 2022), a giant 5-Mpc radio galaxy (Oei et al. 2022) and many others. Even older large surveys, such as FIRST (Becker et al. 1995), have continued to reveal interesting new sources through intensive visible inspection in projects such as Radio Galaxy Zoo (Banfield et al. 2015, 2016) . However, these discoveries were made by scientists and citizen scientists serendipitously noticing the unusual source and the increasing volume of modern datasets means that many interesting sources may be missed. An alternative to manual search is machine learning: a set of algorithms designed to automatically learn patterns and models from data, which has the potential to assist in rapidly sorting through data to locate interesting sources in large astronomical datasets. Recent unsupervised machine learning approaches have proven very effective at discovering radio  \n★ E-mail: [dr.michelle.lochner@gmail.com](dr.michelle.lochner@gmail.com)  \ngalaxies with unusual morphology (Galvin et al. 2020; Mostert et al. 2021; Gupta et al. 2022) .  \nAstronomaly (Lochner & Bassett 2021) is a general machine learning framework for anomaly detection in astronomical data. It uses a novel active learning approach to optimally com","cbCaie1KuBdl3aKo","https://ap.wps.com/l/cbCaie1KuBdl3aKo","pdf",2169915,1,7,"English","en",105,"# Abstract\n# Introduction\n## Astronomical surveys and the challenge of missed sources\n## Unsupervised machine learning and anomaly detection\n# Methodology\n## Source detection with PyBDSF and construction of morphological catalogues\n# Results\n# Discussion\n## Physical models for the source\n# Conclusion","[{\"question\":\"What method was used to discover the ring-like radio source in MGCLS?\",\"answer\":\"A machine learning anomaly detection approach, using the Astronomaly framework, was used to search for unusually shaped sources and flag a unique morphology that scientists missed.\"},{\"question\":\"What are the main observed structural features of the source?\",\"answer\":\"The source shows a large emission ring (~175 kpc across) with quadrilateral enhanced-brightness regions resembling radio jets, plus two “ears” separated by 368 kpc and a diffuse envelope.\"},{\"question\":\"Why are simple physical explanations considered insufficient?\",\"answer\":\"The source’s overall morphology and steep spectral properties do not match easily with straightforward models, and several proposed scenarios (starburst termination shock, end-on radio galaxy, or black hole merger) fail to provide a clear, single explanation.\"}]","A Unique, Ring-like Radio Source with Quadrilateral Structure Detected with Machine Learning - Accepted Manuscript | PDF",1785817391,18,{"code":4,"msg":31,"data":32},"ok",{"site_id":24,"language":23,"slug":33,"title":13,"keywords":34,"description":14,"schema_data":35,"social_meta":86,"head_meta":88,"extra_data":90,"updated_unix":28},"a-unique-ring-like-radio-source-with-quadrilateral-structure-detected-with-machine-learning-accepted-manuscript","",{"@graph":36,"@context":85},[37,54,68],{"@type":38,"itemListElement":39},"BreadcrumbList",[40,44,48,51],{"item":41,"name":42,"@type":43,"position":20},"https://docshare.wps.com","Home","ListItem",{"item":45,"name":46,"@type":43,"position":47},"https://docshare.wps.com/document/","Document",2,{"item":49,"name":12,"@type":43,"position":50},"https://docshare.wps.com/document/research-report/",3,{"item":52,"name":13,"@type":43,"position":53},"https://docshare.wps.com/document/a-unique-ring-like-radio-source-with-quadrilateral-structure-detected-with-machine-learning-accepted-manuscript/123568/",4,{"url":52,"name":13,"@type":55,"author":56,"headline":13,"publisher":58,"fileFormat":61,"inLanguage":23,"description":14,"dateModified":62,"datePublished":62,"encodingFormat":61,"isAccessibleForFree":63,"interactionStatistic":64},"DigitalDocument",{"name":9,"@type":57},"Person",{"url":41,"name":59,"@type":60},"DocShare","Organization","application/pdf","2026-08-04",true,{"@type":65,"interactionType":66,"userInteractionCount":4},"InteractionCounter",{"@type":67},"ViewAction",{"@type":69,"mainEntity":70},"FAQPage",[71,77,81],{"name":72,"@type":73,"acceptedAnswer":74},"What method was used to discover the ring-like radio source in MGCLS?","Question",{"text":75,"@type":76},"A machine learning anomaly detection approach, using the Astronomaly framework, was used to search for unusually shaped sources and flag a unique morphology that scientists missed.","Answer",{"name":78,"@type":73,"acceptedAnswer":79},"What are the main observed structural features of the source?",{"text":80,"@type":76},"The source shows a large emission ring (~175 kpc across) with quadrilateral enhanced-brightness regions resembling radio jets, plus two “ears” separated by 368 kpc and a diffuse envelope.",{"name":82,"@type":73,"acceptedAnswer":83},"Why are simple physical explanations considered insufficient?",{"text":84,"@type":76},"The source’s overall morphology and steep spectral properties do not match easily with straightforward models, and several proposed scenarios (starburst termination shock, end-on radio galaxy, or black hole merger) fail to provide a clear, single explanation.","https://schema.org",{"og:url":52,"og:type":87,"og:title":13,"og:site_name":59,"og:description":14},"article",{"robots":89,"canonical":52},"index,follow",{"doc_id":7,"site_id":24},{"code":4,"msg":5,"data":92},[93,97,101,105,110,115,119,122,127,130,134],{"id":20,"doc_module":4,"doc_module_name":46,"category_name":94,"show_sort_weight":95,"slug":96},"Story & Novel",90,"story-novel",{"id":47,"doc_module":4,"doc_module_name":46,"category_name":98,"show_sort_weight":99,"slug":100},"Literature",80,"literature",{"id":53,"doc_module":4,"doc_module_name":46,"category_name":102,"show_sort_weight":103,"slug":104},"Exam",70,"exam",{"id":106,"doc_module":4,"doc_module_name":46,"category_name":107,"show_sort_weight":108,"slug":109},5,"Comic",60,"comic",{"id":111,"doc_module":4,"doc_module_name":46,"category_name":112,"show_sort_weight":113,"slug":114},6,"Technology",50,"technology",{"id":21,"doc_module":4,"doc_module_name":46,"category_name":116,"show_sort_weight":117,"slug":118},"Healthcare",40,"healthcare",{"id":11,"doc_module":4,"doc_module_name":46,"category_name":12,"show_sort_weight":120,"slug":121},30,"research-report",{"id":123,"doc_module":4,"doc_module_name":46,"category_name":124,"show_sort_weight":125,"slug":126},9,"Religion & Spirituality",20,"religion-spirituality",{"id":125,"doc_module":4,"doc_module_name":46,"category_name":128,"show_sort_weight":125,"slug":129},"World Cup","world-cup",{"id":131,"doc_module":4,"doc_module_name":46,"category_name":132,"show_sort_weight":131,"slug":133},10,"Lifestyle","lifestyle",{"id":135,"doc_module":4,"doc_module_name":46,"category_name":136,"show_sort_weight":106,"slug":137},19,"General","general"]