{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,7]],"date-time":"2026-04-07T14:24:36Z","timestamp":1775571876869,"version":"3.50.1"},"reference-count":61,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2023,10,3]],"date-time":"2023-10-03T00:00:00Z","timestamp":1696291200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>We study matter accretion in a static, axially symmetric and vacuum geometry describing the exterior gravitational field of a black hole mimicker called the \u03b3 metric. We evaluate the thermal and optical properties of thin accretion disks, including the emission rate, luminosity and shadow, in the gamma spacetime. Also, we explore the radial accretion of polytropic matter fields onto the central source and evaluate the thermal and optical properties of the infalling gas, such as temperature and luminosity. The results are discussed in the context of evaluating the possibility that the true nature of astrophysical black hole candidates may not be a black hole but some exotic compact object possessing a non-vanishing mass quadrupole moment.<\/jats:p>","DOI":"10.3390\/sym15101858","type":"journal-article","created":{"date-parts":[[2023,10,4]],"date-time":"2023-10-04T07:47:52Z","timestamp":1696405672000},"page":"1858","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Observable Properties of Thin Accretion Disk in the \u03b3 Spacetime"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1502-2053","authenticated-orcid":false,"given":"Bobur","family":"Turimov","sequence":"first","affiliation":[{"name":"School of Applied Mathematics, New Uzbekistan University, Mustaqillik Avenue 54, Tashkent 100007, Uzbekistan"},{"name":"School of Engineering, Central Asian University, Milliy Bog St. 264, Tashkent 111221, Uzbekistan"},{"name":"Ulugh Beg Astronomical Institute, Astronomy St. 33, Tashkent 100052, Uzbekistan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1232-610X","authenticated-orcid":false,"given":"Bobomurat","family":"Ahmedov","sequence":"additional","affiliation":[{"name":"Ulugh Beg Astronomical Institute, Astronomy St. 33, Tashkent 100052, Uzbekistan"},{"name":"Institute of Fundamental and Applied Research, National Research University TIIAME, Kori Niyoziy 39, Tashkent 100000, Uzbekistan"},{"name":"Institute of Theoretical Physics, National University of Uzbekistan, Tashkent 100174, Uzbekistan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,10,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"L1","DOI":"10.3847\/2041-8213\/ab0ec7","article-title":"First M87 Event Horizon Telescope Results. 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