{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,8]],"date-time":"2026-10-08T13:02:01Z","timestamp":1791464521157,"version":"4.3.4"},"reference-count":16,"publisher":"AIP Publishing","issue":"10","funder":[{"DOI":"10.13039\/501100014188","name":"Ministry of Science and ICT, South Korea","doi-asserted-by":"publisher","award":["EN2603-2"],"award-info":[{"award-number":["EN2603-2"]}],"id":[{"id":"10.13039\/501100014188","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["pubs.aip.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2026,10,1]]},"abstract":"<jats:p>The radial electric field (Er) is important for turbulence suppression and transport barrier formation in magnetically confined plasmas. To establish the diagnostic capability required for its future determination, the Korea Superconducting Tokamak Advanced Research (KSTAR) Motional Stark Effect Background Polychromator was modified to measure the polarization angles of the full-energy \u03c0 and half-energy \u03c3 Stark components simultaneously along a common line of sight (LOS). Interference filters and operating temperatures were selected using the calculated Stark spectra and the existing filter inventory. The modified configuration was implemented on seven lines of sight and evaluated in four KSTAR discharges at a toroidal magnetic field of 2.5\u00a0T with a continuously injected 90-keV neutral beam injection 1-B diagnostic beam. Usable simultaneous measurements were obtained from four lines of sight. The polarization angle difference, \u0394\u03b3 = \u03b3F \u2212 \u03b3H, exhibited distinguishable temporal and channel-dependent responses under internal transport barrier and off-axis neutral-beam-current-drive scenarios. The propagated statistical uncertainties of the reference-subtracted 1-s mean values ranged from \u223c0.010\u00b0 to 0.079\u00b0. At LOS 14, the peak changes in two off-axis discharges were 0.358\u00b0 \u00b1 0.028\u00b0 and 0.365\u00b0 \u00b1 0.028\u00b0; their 0.007\u00b0 difference was smaller than the combined statistical uncertainty of 0.039\u00b0. These results demonstrate the feasibility of simultaneously resolving full- and half-energy Stark polarization responses using the existing KSTAR diagnostic infrastructure, providing an experimental basis for future quantitative Er reconstruction through updated calibration and complete forward analysis development.<\/jats:p>","DOI":"10.1063\/5.0350847","type":"journal-article","created":{"date-parts":[[2026,10,8]],"date-time":"2026-10-08T12:42:08Z","timestamp":1791463328000},"update-policy":"https:\/\/doi.org\/10.1063\/aip-crossmark-policy-page","source":"Crossref","is-referenced-by-count":0,"title":["Simultaneous full- and half-energy Stark polarization measurements using a modified background polychromator motional Stark effect system"],"prefix":"10.1063","volume":"97","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-9354-4826","authenticated-orcid":false,"given":"Juyoung","family":"Ko","sequence":"first","affiliation":[{"name":"Korea Institute of Fusion Energy , Daejeon,","place":["Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5501-3939","authenticated-orcid":false,"given":"Jinseok","family":"Ko","sequence":"additional","affiliation":[{"name":"Korea Institute of Fusion Energy , Daejeon,","place":["Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"317","published-online":{"date-parts":[[2026,10,8]]},"reference":[{"key":"2026100808420077000_c1","doi-asserted-by":"publisher","first-page":"060501","DOI":"10.1063\/1.5142734","article-title":"Role of sheared E \u00d7 B flow in self-organized, improved confinement states in magnetized plasmas","volume":"27","year":"2020","journal-title":"Phys. Plasmas"},{"key":"2026100808420077000_c2","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1063\/1.859529","article-title":"Influence of sheared poloidal rotation on edge turbulence","volume":"2","year":"1990","journal-title":"Phys. Fluids B"},{"key":"2026100808420077000_c3","doi-asserted-by":"publisher","first-page":"1499","DOI":"10.1063\/1.872367","article-title":"Effects of E \u00d7 B velocity shear and magnetic shear on turbulence and transport in magnetic confinement devices","volume":"4","year":"1997","journal-title":"Phys. Plasmas"},{"key":"2026100808420077000_c4","doi-asserted-by":"publisher","first-page":"109","DOI":"10.1103\/revmodphys.72.109","article-title":"Suppression of turbulence and transport by sheared flow","volume":"72","year":"2000","journal-title":"Rev. Mod. 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Y.-H.\n            Yuh\n          , \u201cThe motional stark effect diagnostic on Alcator C-Mod,\u201d Ph.D. thesis, Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, 2005."},{"key":"2026100808420077000_c9","unstructured":"R. T.\n            Mumgaard\n          , \u201cLower hybrid current drive on Alcator C-Mod: Measurements with an upgraded MSE diagnostic and comparisons to simulation,\u201d Ph.D. thesis, Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, 2015."},{"key":"2026100808420077000_c10","doi-asserted-by":"publisher","first-page":"033513","DOI":"10.1063\/5.0040823","article-title":"Application of motional Stark effect in situ background correction to a superconducting tokamak","volume":"92","year":"2021","journal-title":"Rev. Sci. 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