{"title":"结合氦碰撞-辐射模型中重吸收过程的中性氦谱线强度改进分析","authors":"K. Lin, M. Goto, H. Akatsuka","doi":"10.3390/atoms11060094","DOIUrl":null,"url":null,"abstract":"In this study, eight emission lines in the visible wavelength range of neutral helium were used to diagnose the electron density and temperature of the Large Helical Device (LHD) helium plasma instead of the conventional three-line method. The collisional-radiative (CR) model for low-pressure helium plasma was revised to include the optical escape factors for spontaneous transition from the n1P states to the ground state so that the influence of the absorption effect under optically thick conditions could be considered. The developed algorithm was based on fitting the number densities of eight excited states obtained using optical emission spectroscopy (OES). The electron density, electron temperature, ground-state density, and optical escape factors were selected as the fitting parameters. The objective function was set as the summation of the residual errors between the number densities measured in the experiment and those calculated using the revised model. A regularization term was introduced for the optical escape factor and optimized through bias and variance analyses. The results show that the agreement between the number density calculated by the algorithm and its counterpart measured in the experiment was generally improved compared to the method using three lines.","PeriodicalId":8629,"journal":{"name":"Atoms","volume":null,"pages":null},"PeriodicalIF":1.7000,"publicationDate":"2023-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Improved Line Intensity Analysis of Neutral Helium by Incorporating the Reabsorption Processes in a Helium Collisional-Radiative Model\",\"authors\":\"K. Lin, M. Goto, H. Akatsuka\",\"doi\":\"10.3390/atoms11060094\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"In this study, eight emission lines in the visible wavelength range of neutral helium were used to diagnose the electron density and temperature of the Large Helical Device (LHD) helium plasma instead of the conventional three-line method. The collisional-radiative (CR) model for low-pressure helium plasma was revised to include the optical escape factors for spontaneous transition from the n1P states to the ground state so that the influence of the absorption effect under optically thick conditions could be considered. The developed algorithm was based on fitting the number densities of eight excited states obtained using optical emission spectroscopy (OES). The electron density, electron temperature, ground-state density, and optical escape factors were selected as the fitting parameters. The objective function was set as the summation of the residual errors between the number densities measured in the experiment and those calculated using the revised model. A regularization term was introduced for the optical escape factor and optimized through bias and variance analyses. The results show that the agreement between the number density calculated by the algorithm and its counterpart measured in the experiment was generally improved compared to the method using three lines.\",\"PeriodicalId\":8629,\"journal\":{\"name\":\"Atoms\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":1.7000,\"publicationDate\":\"2023-06-08\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Atoms\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.3390/atoms11060094\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"PHYSICS, ATOMIC, MOLECULAR & CHEMICAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Atoms","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.3390/atoms11060094","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"PHYSICS, ATOMIC, MOLECULAR & CHEMICAL","Score":null,"Total":0}
Improved Line Intensity Analysis of Neutral Helium by Incorporating the Reabsorption Processes in a Helium Collisional-Radiative Model
In this study, eight emission lines in the visible wavelength range of neutral helium were used to diagnose the electron density and temperature of the Large Helical Device (LHD) helium plasma instead of the conventional three-line method. The collisional-radiative (CR) model for low-pressure helium plasma was revised to include the optical escape factors for spontaneous transition from the n1P states to the ground state so that the influence of the absorption effect under optically thick conditions could be considered. The developed algorithm was based on fitting the number densities of eight excited states obtained using optical emission spectroscopy (OES). The electron density, electron temperature, ground-state density, and optical escape factors were selected as the fitting parameters. The objective function was set as the summation of the residual errors between the number densities measured in the experiment and those calculated using the revised model. A regularization term was introduced for the optical escape factor and optimized through bias and variance analyses. The results show that the agreement between the number density calculated by the algorithm and its counterpart measured in the experiment was generally improved compared to the method using three lines.
AtomsPhysics and Astronomy-Nuclear and High Energy Physics
CiteScore
2.70
自引率
22.20%
发文量
128
审稿时长
8 weeks
期刊介绍:
Atoms (ISSN 2218-2004) is an international and cross-disciplinary scholarly journal of scientific studies related to all aspects of the atom. It publishes reviews, regular research papers, and communications; there is no restriction on the length of the papers. Our aim is to encourage scientists to publish their experimental and theoretical research in as much detail as possible. Full experimental and/or methodical details must be provided for research articles. There are, in addition, unique features of this journal: -manuscripts regarding research proposals and research ideas will be particularly welcomed. -computed data, program listings, and files regarding the full details of the experimental procedure, if unable to be published in a normal way, can be deposited as supplementary material. Scopes: -experimental and theoretical atomic, molecular, and nuclear physics, chemical physics -the study of atoms, molecules, nuclei and their interactions and constituents (protons, neutrons, and electrons) -quantum theory, applications and foundations -microparticles, clusters -exotic systems (muons, quarks, anti-matter) -atomic, molecular, and nuclear spectroscopy and collisions -nuclear energy (fusion and fission), radioactive decay -nuclear magnetic resonance (NMR) and electron spin resonance (ESR), hyperfine interactions -orbitals, valence and bonding behavior -atomic and molecular properties (energy levels, radiative properties, magnetic moments, collisional data) and photon interactions