{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,13]],"date-time":"2026-10-13T13:46:59Z","timestamp":1791899219374,"version":"4.3.4"},"reference-count":9,"publisher":"AIP Publishing","issue":"10","funder":[{"DOI":"10.13039\/100000015","name":"U.S. Department of Energy","doi-asserted-by":"publisher","award":["DE-AC05-00OR22725"],"award-info":[{"award-number":["DE-AC05-00OR22725"]}],"id":[{"id":"10.13039\/100000015","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>Oak Ridge National Laboratory (ORNL) has been developing RF-driven, linear plasma devices for plasma\u2013material interaction (PMI) studies. The physics basis for the Material Plasma Exposure eXperiment (MPEX), under construction at ORNL, was established through experimental measurements on the Proto-MPEX device. The Proto-MPEX device has recently been reconfigured as the \u201cProto-Lite\u201d platform, with the removal of auxiliary electron and ion heating capabilities and the reduction of the number of magnet coils from 13 to 8. Proto-Lite is a risk-reduction platform for MPEX, where helicon wave RF-technologies can be tested, plasma scenarios developed, new workforce members trained, diagnostic systems explored, and control architectures vetted, in addition to short-pulse PMI target exposures. The diagnostic suite for Proto-Lite largely consists of systems that were ported from Proto-MPEX or that are being readied for deployment on MPEX. The current Proto-Lite diagnostic set includes (typical achieved range; data rate): double Langmuir probes (Te \u223c 1\u201320\u00a0eV, ne \u223c 1018\u20131020\u00a0m\u22123; 1\u00a0kHz), infrared camera imaging (T \u223c 20\u2013150\u2009\u00b0C; 50\u00a0Hz full frame), filtered visible camera imaging (1\u201318 kfps), neutral pressure gauges (P \u223c 10\u22124\u201310\u22122 Torr; 100\u00a0Hz), residual gas mass spectroscopy (1\u2013100\u00a0amu), survey (400\u2013900\u00a0nm; 1\u00a0Hz), and high-resolution optical emission spectroscopy (200\u00a0Hz). Plasma exposed samples are removed via a vacuum load-lock for ex situ analysis. This paper will give an overview of experimental measurements from Proto-Lite diagnostic systems and describe how those systems are contributing to risk-reduction research for MPEX.<\/jats:p>","DOI":"10.1063\/5.0350530","type":"journal-article","created":{"date-parts":[[2026,10,13]],"date-time":"2026-10-13T12:57:58Z","timestamp":1791896278000},"update-policy":"https:\/\/doi.org\/10.1063\/aip-crossmark-policy-page","source":"Crossref","is-referenced-by-count":0,"title":["Overview of the diagnostic suite for the Proto-Lite experiment"],"prefix":"10.1063","volume":"97","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7456-3509","authenticated-orcid":false,"given":"T. M.","family":"Biewer","sequence":"first","affiliation":[{"name":"Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0609-1164","authenticated-orcid":false,"given":"J. B. O.","family":"Caughman","sequence":"additional","affiliation":[{"name":"Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3549-6013","authenticated-orcid":false,"given":"G. D.","family":"Dhamale","sequence":"additional","affiliation":[{"name":"Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0390-9984","authenticated-orcid":false,"given":"K.","family":"Fujii","sequence":"additional","affiliation":[{"name":"Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5640-5854","authenticated-orcid":false,"given":"C.","family":"Johnson","sequence":"additional","affiliation":[{"name":"Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8952-7180","authenticated-orcid":false,"given":"J.","family":"Larson","sequence":"additional","affiliation":[{"name":"Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7248-0646","authenticated-orcid":false,"given":"Y.","family":"Wang","sequence":"additional","affiliation":[{"name":"Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1353-8865","authenticated-orcid":false,"given":"E. 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