{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T11:19:06Z","timestamp":1788261546768,"version":"build-2803163510"},"reference-count":29,"publisher":"IOP Publishing","issue":"17","license":[{"start":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T00:00:00Z","timestamp":1788220800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/publishingsupport.iopscience.iop.org\/iop-standard\/v1"},{"start":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T00:00:00Z","timestamp":1788220800000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/iopscience.iop.org\/info\/page\/text-and-data-mining"}],"funder":[{"name":"JSPS KAKENHI","award":["22H03019"],"award-info":[{"award-number":["22H03019"]}]},{"name":"JST ERATO","award":["JPMJER2102"],"award-info":[{"award-number":["JPMJER2102"]}]}],"content-domain":{"domain":["iopscience.iop.org"],"crossmark-restriction":false},"short-container-title":["Phys. Med. Biol."],"published-print":{"date-parts":[[2026,9,14]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>\n                    <jats:italic>Objective<\/jats:italic>\n                    . Linear energy transfer (LET) measurements of\n                    <jats:italic>\u03b1<\/jats:italic>\n                    -particles are increasingly important for micro-dosimetric evaluation in targeted\n                    <jats:italic>\u03b1<\/jats:italic>\n                    -radionuclide therapy. However, direct LET measurements remain challenging due to the extremely short range of\n                    <jats:italic>\u03b1<\/jats:italic>\n                    -particles in matter. In this study, we propose a method to estimate LET distributions using quenching effects observed in\n                    <jats:italic>\u03b1<\/jats:italic>\n                    -particle trajectory images.\n                    <jats:italic>Approach. \u03b1<\/jats:italic>\n                    -particle trajectories were imaged using an ultra-high-resolution imaging system consisting of a Gd\n                    <jats:sub>3<\/jats:sub>\n                    Al\n                    <jats:sub>2<\/jats:sub>\n                    Ga\n                    <jats:sub>3<\/jats:sub>\n                    O\n                    <jats:sub>12<\/jats:sub>\n                    scintillator, an optical magnification unit, and an electron-multiplying charge-coupled device camera.\n                    <jats:italic>\u03b1<\/jats:italic>\n                    -particles from three radionuclides were measured: Am-241 (5.5 MeV), Po-213 (8.4 MeV) and Po-212 (8.8 MeV). LET distributions were estimated by taking the ratio of simulated dose profiles (without quenching) to measured depth profiles of\n                    <jats:italic>\u03b1<\/jats:italic>\n                    -particle trajectory images (including quenching). The estimated LET distributions were then compared with those obtained from simulations.\n                    <jats:italic>Main results<\/jats:italic>\n                    . The relative LET distributions along the depth direction were successfully estimated from the measured depth profiles for all\n                    <jats:italic>\u03b1<\/jats:italic>\n                    -particles with different energies. The estimated relative LET distributions differed from the simulated distributions by no more than 11%\u201324% over the depth range from 5\n                    <jats:italic>\u00b5<\/jats:italic>\n                    m to the Bragg peak position. Approximate absolute LET distributions were also evaluated.\n                    <jats:italic>Significance<\/jats:italic>\n                    . The proposed method enables a simple and effective estimation of LET distributions of\n                    <jats:italic>\u03b1<\/jats:italic>\n                    -particles from measured depth profiles of trajectory images. It is applicable to\n                    <jats:italic>\u03b1<\/jats:italic>\n                    -particles with a wide range of energies and has potential for advancing micro-dosimetry in targeted\n                    <jats:italic>\u03b1<\/jats:italic>\n                    -radionuclide therapy.\n                  <\/jats:p>","DOI":"10.1088\/1361-6560\/ae99a7","type":"journal-article","created":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T10:57:03Z","timestamp":1788260223000},"page":"175003","update-policy":"https:\/\/doi.org\/10.1088\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Estimation of LET distributions of\n                    <i>\u03b1<\/i>\n                    -particles from measured scintillator-based trajectory images"],"prefix":"10.1088","volume":"71","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1280-0043","authenticated-orcid":true,"given":"Seiichi","family":"Yamamoto","sequence":"first","affiliation":[{"name":"Waseda University"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3135-1017","authenticated-orcid":true,"given":"Kohei","family":"Nakanishi","sequence":"additional","affiliation":[{"name":"Nagoya University Graduate School of Medicine"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9555-2147","authenticated-orcid":true,"given":"Katsunori","family":"Yogo","sequence":"additional","affiliation":[{"name":"Nagoya University Graduate School of Medicine"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Masao","family":"Yoshino","sequence":"additional","affiliation":[{"name":"New Industry Creation Hatchery Center, Tohoku University"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kazuaki","family":"Tsukada","sequence":"additional","affiliation":[{"name":"Research Center for Accelerator and Radioisotope Science (RARiS), Tohoku University"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hidetoshi","family":"Kikunaga","sequence":"additional","affiliation":[{"name":"Research Center for Accelerator and Radioisotope Science (RARiS), Tohoku University"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Takuya","family":"Yokokita","sequence":"additional","affiliation":[{"name":"Research Center for Accelerator and Radioisotope Science (RARiS), Tohoku University"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kenji","family":"Shirasaki","sequence":"additional","affiliation":[{"name":"Institute for Radiation Science, The University of Osaka"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kei","family":"Kamada","sequence":"additional","affiliation":[{"name":"New Industry Creation Hatchery Center, Tohoku University"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Akira","family":"Yoshikawa","sequence":"additional","affiliation":[{"name":"New Industry Creation Hatchery Center, Tohoku University"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jun","family":"Kataoka","sequence":"additional","affiliation":[{"name":"Waseda University"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"266","published-online":{"date-parts":[[2026,9,1]]},"reference":[{"key":"pmbae99a7bib1","doi-asserted-by":"publisher","first-page":"250","DOI":"10.1016\/S0168-9002(03)01368-8","type":"journal-article","article-title":"GEANT4: a simulation toolkit","volume":"506","author":"Agostinelli","year":"2003","journal-title":"Nucl. 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All rights, including for text and data mining, AI training, and similar technologies, are reserved.","name":"copyright_information","label":"Copyright Information"},{"value":"2026-05-20","name":"date_received","label":"Date Received","group":{"name":"publication_dates","label":"Publication dates"}},{"value":"2026-08-13","name":"date_accepted","label":"Date Accepted","group":{"name":"publication_dates","label":"Publication dates"}},{"value":"2026-09-01","name":"date_epub","label":"Online publication date","group":{"name":"publication_dates","label":"Publication dates"}}]}}