{"created":"2023-06-20T13:20:28.979837+00:00","id":502,"links":{},"metadata":{"_buckets":{"deposit":"c7bdcb63-1af0-425c-86e5-2b77d8cda4b8"},"_deposit":{"created_by":1,"id":"502","owners":[1],"pid":{"revision_id":0,"type":"depid","value":"502"},"status":"published"},"_oai":{"id":"oai:ir.soken.ac.jp:00000502","sets":["2:427:12"]},"author_link":["8672","8673","8674"],"item_1_creator_2":{"attribute_name":"著者名","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{"creatorName":"鄒, 士陽"}],"nameIdentifiers":[{}]}]},"item_1_creator_3":{"attribute_name":"フリガナ","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{"creatorName":"ゾウ, シヤン"}],"nameIdentifiers":[{}]}]},"item_1_date_granted_11":{"attribute_name":"学位授与年月日","attribute_value_mlt":[{"subitem_dategranted":"2003-03-24"}]},"item_1_degree_grantor_5":{"attribute_name":"学位授与機関","attribute_value_mlt":[{"subitem_degreegrantor":[{"subitem_degreegrantor_name":"総合研究大学院大学"}]}]},"item_1_degree_name_6":{"attribute_name":"学位名","attribute_value_mlt":[{"subitem_degreename":"博士（理学）"}]},"item_1_description_12":{"attribute_name":"要旨","attribute_value_mlt":[{"subitem_description":"　　Collision processes of low charged ions with neutral atomic particles at low to intermediate energies play vital roles in various fields of applied physics such as plasma physics, astrophysics, and radiation physics.  In ion-atom collisions, several inelastic processes can take place in addition to elastic scattering.  Among these processes, excitation of target, electron capture, and ionization (the election of electrons from the target) are considered to be dominate in the energy range concerned fusion research.  There is an amount of effort to fully understand the dynamics of ion-atom collisions from both the experimental and theoretical perspectives.  As a result of these extensive experimental and theoretical investigations, most of the elastic and inelastic processes involving bound states of target and projectile ions are well described by current theories.  However, ionization remains a challenge even for the most basic processes such as proton-hydrogen system especially at low energy.  The discrepancy in ionization cross sections between two recent experiments, i.e. Shah et al. (1998) and Pieksrna et al. (1994) is as large as a factor of six.  Reasonably reliable theoretical studies of Sidky et al. (2001), Toshima (1999) and Kolakowska et al. (1999) predicted about 20% higher value than those of experiments of Shah et al. (1981,1987) at the peak of ionization cross section, and there is a considerable disagreement among theoretical cross sections at low keV energies.  The energy dependence of theoretical and experimental results is also different.  In the present work, we have aimed to provide more insight into such unresolved problems.<br />　　Heavy-particle atomic collision is a complex quantum-mechanical problem.  It involves interaction of many states both from the discrete and continuum parts of the energy spectrum and also strong couplings of many reaction channels.  Obviously, the understanding of the collisional dynamics of ion-atom system would represent a considerable advance of our basic knowledge on atomic interactions, in general.  Besides, this knowledge is essential for the understanding and interpretation of a large variety of phenomena taking part in many non-equilibrium plasmas.  The importance of heavy-particle collisions in fusion research applications and the challenges for theory have motivated me to carry out this research.<br />　　In the first part of my research, I studied electron emission in H+ + H(1s), He2+ + H(1s) and He+(1s) + H+ collisions at low energy (below 20 keV /amu), using the electron translation factor corrected molecular orbital close-coupling approach.  Selection of the collision partners and energy range studied here ties closely with the application in fusion plasma experiments.  Full convergence of ionization cross sections as a function of H2+ or HeH2+ molecular basis size was achieved by including up to twenty bound states, and more than three hundred continuum states.  The results obtained by our calculation are compared with the available experimental data and various theoretical models.  Excellent agreement with the recent experiments is found for the total ionization cross sections where the experimental values are available.  This study shows that for the ionization in He2+ + H(1s) and/or He+(1s) + H+ collisions, the higher-level ladder climbing processes (i.e.  excitation  via a sequence of upper levels) are dominant as compared to direct mechanism, in which the electron is liberated by one step promotion.  On the contrary, in the H+ + H(1s) collision process, H2+ is ionized directly, and the higher levels, especially 2pπu act as a temporary trap of the ionization flux.<br />　　The second part of this thesis is devoted to the calculation of spectral profiles of Li2+ ions emitted in magnetically confined plasma.  In magnetic confined plasmas, Li2+ forms are populated by three kinds of mechanism;  excitation from the ground state, electron-ion recombination from Li3+ and charge exchange with neutral hydrogen and Li3+.  The nl-resolved population densities of exited Li2+ ions are calculated up to n=2O using a collisional-radiative model including the charge exchange process.  Since reliable cross sections for charge exchange processes in Li3+ + H(1s) collision are available, instead of attempting recalculations of charge transfer process, I adopt them from the recent literatures.  In the calculation, the radiative transition probabilities and wavelengths of Li2+ ions are computed by diagonalizing the Hamiltonian including interactions with the magnetic field.  This study shows that 1) spectral profiles emitted by excitation, recombination and charge exchange are quite different from each other, which is due to the different n and l-distributions of the rate coefficients of such basic atomic processes (i.e. excitation, recombination and charge exchange);  and 2) in order to interpret properly low temperature spectra, the Zeeman effect has to be accounted for, especially for ion temperature diagnostics.<br />　　In summary, I have treated heavy-particle atomic collisions, which are typical in plasma, obtaining new cross sections for charge transfer, excitation and ionization at low energies.  The detailed discussions are made to collisions involving the partially or fully ionized main component of fusion plasmas (hydrogen and helium).  Based on a detailed computation for spectral profiles of Li2+ ions, I have analyzed the spectra of hydrogen-like lithium measured from magnetic confinement fusion plasmas.","subitem_description_type":"Other"}]},"item_1_description_7":{"attribute_name":"学位記番号","attribute_value_mlt":[{"subitem_description":"総研大甲第674号","subitem_description_type":"Other"}]},"item_1_select_14":{"attribute_name":"所蔵","attribute_value_mlt":[{"subitem_select_item":"有"}]},"item_1_select_8":{"attribute_name":"研究科","attribute_value_mlt":[{"subitem_select_item":"数物科学研究科"}]},"item_1_select_9":{"attribute_name":"専攻","attribute_value_mlt":[{"subitem_select_item":"10 核融合科学専攻"}]},"item_1_text_10":{"attribute_name":"学位授与年度","attribute_value_mlt":[{"subitem_text_value":"2002"}]},"item_creator":{"attribute_name":"著者","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{"creatorName":"ZOU, Shi-Yang","creatorNameLang":"en"}],"nameIdentifiers":[{}]}]},"item_files":{"attribute_name":"ファイル情報","attribute_type":"file","attribute_value_mlt":[{"accessrole":"open_date","date":[{"dateType":"Available","dateValue":"2016-02-17"}],"displaytype":"simple","filename":"甲674_要旨.pdf","filesize":[{"value":"479.5 kB"}],"format":"application/pdf","licensetype":"license_11","mimetype":"application/pdf","url":{"label":"要旨・審査要旨 / Abstract, Screening Result","url":"https://ir.soken.ac.jp/record/502/files/甲674_要旨.pdf"},"version_id":"a381f3bc-1c15-4d02-acb7-c7a167576494"},{"accessrole":"open_date","date":[{"dateType":"Available","dateValue":"2016-02-17"}],"displaytype":"simple","filename":"甲674_本文.pdf","filesize":[{"value":"6.4 MB"}],"format":"application/pdf","licensetype":"license_11","mimetype":"application/pdf","url":{"label":"本文","url":"https://ir.soken.ac.jp/record/502/files/甲674_本文.pdf"},"version_id":"4cd85565-70ee-413c-acaa-ee6359987eb9"}]},"item_language":{"attribute_name":"言語","attribute_value_mlt":[{"subitem_language":"eng"}]},"item_resource_type":{"attribute_name":"資源タイプ","attribute_value_mlt":[{"resourcetype":"thesis","resourceuri":"http://purl.org/coar/resource_type/c_46ec"}]},"item_title":"Collision Processes of Low Charge Ions with Atoms in Fusion Plasma","item_titles":{"attribute_name":"タイトル","attribute_value_mlt":[{"subitem_title":"Collision Processes of Low Charge Ions with Atoms in Fusion Plasma"},{"subitem_title":"Collision Processes of Low Charge Ions with Atoms in Fusion Plasma","subitem_title_language":"en"}]},"item_type_id":"1","owner":"1","path":["12"],"pubdate":{"attribute_name":"公開日","attribute_value":"2010-02-22"},"publish_date":"2010-02-22","publish_status":"0","recid":"502","relation_version_is_last":true,"title":["Collision Processes of Low Charge Ions with Atoms in Fusion Plasma"],"weko_creator_id":"1","weko_shared_id":1},"updated":"2023-06-20T14:53:06.914694+00:00"}