{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,26]],"date-time":"2025-11-26T16:39:37Z","timestamp":1764175177633,"version":"3.37.3"},"reference-count":11,"publisher":"IOP Publishing","issue":"01","license":[{"start":{"date-parts":[[2022,1,5]],"date-time":"2022-01-05T00:00:00Z","timestamp":1641340800000},"content-version":"vor","delay-in-days":4,"URL":"https:\/\/iopscience.iop.org\/page\/copyright"},{"start":{"date-parts":[[2022,1,5]],"date-time":"2022-01-05T00:00:00Z","timestamp":1641340800000},"content-version":"tdm","delay-in-days":4,"URL":"https:\/\/iopscience.iop.org\/info\/page\/text-and-data-mining"}],"content-domain":{"domain":["iopscience.iop.org"],"crossmark-restriction":false},"short-container-title":["J. Inst."],"published-print":{"date-parts":[[2022,1,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:p>The high-field side high-density (HFSHD) region at ASDEX Upgrade (AUG) is a well-documented phenomenon leading to a dense plasma in the inner divertor region that expands upwards to the midplane, resulting in poloidally asymmetric scrape-off layer density profiles. This work investigates, via simulation and experiment, whether the HFSHD at the midplane leads to hollow density profiles at the high-field side. Using the frequency-modulated continuous-wave O-mode reflectometer at AUG, experimental evidence has been found of reflection patterns compatible with a hollow density profile that are reproduced by 1D full-wave simulations. Furthermore, this work assesses the uncertainties in the density profile reconstruction as a consequence of the inverted gradient, showing that the presence of an HFSHD may lead to an overestimation of the density in the confined region.<\/jats:p>","DOI":"10.1088\/1748-0221\/17\/01\/c01008","type":"journal-article","created":{"date-parts":[[2022,1,6]],"date-time":"2022-01-06T10:44:23Z","timestamp":1641465863000},"page":"C01008","update-policy":"https:\/\/doi.org\/10.1088\/crossmark-policy","source":"Crossref","is-referenced-by-count":5,"title":["The impact of inverted density gradients on density profiles measured by reflectometry: an experimental and numerical investigation at ASDEX Upgrade"],"prefix":"10.1088","volume":"17","author":[{"given":"D.","family":"Hachmeister","sequence":"first","affiliation":[]},{"given":"C.","family":"Silva","sequence":"additional","affiliation":[]},{"given":"J.","family":"Santos","sequence":"additional","affiliation":[]},{"given":"G.D.","family":"Conway","sequence":"additional","affiliation":[]},{"given":"L.","family":"Gil","sequence":"additional","affiliation":[]},{"given":"A.","family":"Silva","sequence":"additional","affiliation":[]},{"given":"U.","family":"Stroth","sequence":"additional","affiliation":[]},{"given":"J.","family":"Vicente","sequence":"additional","affiliation":[]},{"given":"E.","family":"Wolfrum","sequence":"additional","affiliation":[]}],"member":"266","published-online":{"date-parts":[[2022,1,5]]},"reference":[{"key":"JINST_064P_0921bib1","doi-asserted-by":"publisher","first-page":"541","DOI":"10.1016\/j.jnucmat.2014.12.008","article-title":"Formation of the high density front in the inner far SOL at ASDEX Upgrade and JET","volume":"463","author":"Potzel","year":"2015","journal-title":"J. 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Fusion"},{"article-title":"Poloidal asymmetries at the ASDEX Upgrade tokamak","year":"2018","author":"Guimar\u00e3is","key":"JINST_064P_0921bib11"}],"container-title":["Journal of Instrumentation"],"original-title":[],"link":[{"URL":"https:\/\/iopscience.iop.org\/article\/10.1088\/1748-0221\/17\/01\/C01008","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/iopscience.iop.org\/article\/10.1088\/1748-0221\/17\/01\/C01008\/pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/iopscience.iop.org\/article\/10.1088\/1748-0221\/17\/01\/C01008\/pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/iopscience.iop.org\/article\/10.1088\/1748-0221\/17\/01\/C01008\/pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,1,6]],"date-time":"2022-01-06T10:44:25Z","timestamp":1641465865000},"score":1,"resource":{"primary":{"URL":"https:\/\/iopscience.iop.org\/article\/10.1088\/1748-0221\/17\/01\/C01008"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,1,1]]},"references-count":11,"journal-issue":{"issue":"01","published-online":{"date-parts":[[2022,1,5]]},"published-print":{"date-parts":[[2022,1,1]]}},"URL":"https:\/\/doi.org\/10.1088\/1748-0221\/17\/01\/c01008","relation":{},"ISSN":["1748-0221"],"issn-type":[{"type":"electronic","value":"1748-0221"}],"subject":[],"published":{"date-parts":[[2022,1,1]]},"assertion":[{"value":"The impact of inverted density gradients on density profiles measured by reflectometry: an experimental and numerical investigation at ASDEX Upgrade","name":"article_title","label":"Article Title"},{"value":"Journal of Instrumentation","name":"journal_title","label":"Journal Title"},{"value":"paper","name":"article_type","label":"Article Type"},{"value":"\u00a9 2022 IOP Publishing Ltd and Sissa Medialab","name":"copyright_information","label":"Copyright Information"},{"value":"2021-09-15","name":"date_received","label":"Date Received","group":{"name":"publication_dates","label":"Publication dates"}},{"value":"2021-11-15","name":"date_accepted","label":"Date Accepted","group":{"name":"publication_dates","label":"Publication dates"}},{"value":"2022-01-05","name":"date_epub","label":"Online publication date","group":{"name":"publication_dates","label":"Publication dates"}}]}}