{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T13:02:16Z","timestamp":1790600536230,"version":"4.1.0"},"reference-count":34,"publisher":"AIP Publishing","issue":"9","funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["RS-2022-00155917"],"award-info":[{"award-number":["RS-2022-00155917"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["RS-2026-25545529"],"award-info":[{"award-number":["RS-2026-25545529"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["RS-2026-25473866"],"award-info":[{"award-number":["RS-2026-25473866"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Korea Institute of Fusion Energy","award":["EN2603"],"award-info":[{"award-number":["EN2603"]}],"id":[{"id":"https:\/\/ror.org\/013yz9b19","id-type":"ROR","asserted-by":"crossref"}]}],"content-domain":{"domain":["pubs.aip.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2026,9,1]]},"abstract":"<jats:p>Characterizing the neutral density in the edge region of the magnetically confined plasma is critical for understanding power exhaust, fuel recycling, and the L\u2013H transition. Lyman-\u03b1 emission can offer two advantages over Balmer-\u03b1: higher emission intensity where the edge electron density is below 1019\/m3, and simpler data analysis because the emissivity is directly tied to the ground-state atomic density, with a smaller molecular contribution at low temperatures near a divertor and the magnetic X-point. We report the Korea Superconducting Tokamak Advanced Research (KSTAR) Lyman Alpha Measuring Apparatus (KLAMA), a radial 20-channel system viewing the region near the magnetic X-point and lower divertor, with a radial channel separation of up to 1.3\u00a0cm. KLAMA uses three notch reflective filters designed to provide 13.02% transmission while suppressing the neighboring C-III line by a factor of \u223c14. We have developed a synthetic data algorithm utilizing the Virtual KSTAR platform to optimize the optical design, quantify noise propagation, and build the transfer matrix. The synthetic data algorithm is also used for a Gaussian-process-regularized 2D reconstruction of the neutral density and is expected to be used to generate a forward model for a Bayesian inference analysis in future work. KLAMA has been manufactured and installed on KSTAR, and preliminary data acquired during a disruption are presented.<\/jats:p>","DOI":"10.1063\/5.0350411","type":"journal-article","created":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T12:51:40Z","timestamp":1790599900000},"update-policy":"https:\/\/doi.org\/10.1063\/aip-crossmark-policy-page","source":"Crossref","is-referenced-by-count":0,"title":["Development of Korea Superconducting Tokamak Advanced Researches (KSTAR) Lyman alpha diagnostics and its synthetic data algorithm"],"prefix":"10.1063","volume":"97","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3097-2866","authenticated-orcid":false,"given":"Jae-seok","family":"Lee","sequence":"first","affiliation":[{"name":"Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology 1 , Daejeon 34141,","place":["Republic of Korea"]},{"name":"Korea Institute of Fusion Energy 2 , Daejeon 34133,","place":["Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9214-8445","authenticated-orcid":false,"given":"K. 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