{"_buckets": {"deposit": "a8fe494b-24f7-4ae9-892d-9e6edfbc6292"}, "_deposit": {"created_by": 1, "id": "464", "owners": [1], "pid": {"revision_id": 0, "type": "depid", "value": "464"}, "status": "published"}, "_oai": {"id": "oai:ir.soken.ac.jp:00000464", "sets": ["12"]}, "author_link": ["8574", "8575", "8573"], "item_1_biblio_info_21": {"attribute_name": "書誌情報（ソート用）", "attribute_value_mlt": [{"bibliographicIssueDates": {"bibliographicIssueDate": "1998-03-24", "bibliographicIssueDateType": "Issued"}, "bibliographic_titles": [{}]}]}, "item_1_creator_2": {"attribute_name": "著者名", "attribute_type": "creator", "attribute_value_mlt": [{"creatorNames": [{"creatorName": "西村, 伸"}], "nameIdentifiers": [{"nameIdentifier": "8573", "nameIdentifierScheme": "WEKO"}]}]}, "item_1_creator_3": {"attribute_name": "フリガナ", "attribute_type": "creator", "attribute_value_mlt": [{"creatorNames": [{"creatorName": "ニシムラ, シン"}], "nameIdentifiers": [{"nameIdentifier": "8574", "nameIdentifierScheme": "WEKO"}]}]}, "item_1_date_granted_11": {"attribute_name": "学位授与年月日", "attribute_value_mlt": [{"subitem_dategranted": "1998-03-24"}]}, "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_1": {"attribute_name": "ID", "attribute_value_mlt": [{"subitem_description": "1998024", "subitem_description_type": "Other"}]}, "item_1_description_12": {"attribute_name": "要旨", "attribute_value_mlt": [{"subitem_description": "The radial electric fields in magnetically confined toroidal plasmas are\u003cbr\u003e considered to play an important role in plasma confinements.  For\u003cbr\u003eexample, they change the neoclassical ripple loss in the low collisionality\u003cbr\u003eregime in helical devices, and they are considered to be the important\u003cbr\u003eparameter to determine the L/H transition and the anomalous transport\u003cbr\u003echaracteristics of L/H-modes in tokamak plasmas.  Therefore many efforts\u003cbr\u003eto study the radial electric fields experimentally have been performed.\u003cbr\u003eOne method for this study is the spectroscopic measurements of the\u003cbr\u003erotations of impurity ions.  However, toroidal effects on the plasma\u003cbr\u003erotations have never been studied experimentally.  The coupling of\u003cbr\u003etoroidal and poloidal rotations caused by the toroidal effect to satisfy the\u003cbr\u003epoloidal flow conservation condition is the most important basis of\u003cbr\u003e neoclassical transport theory and is also important for understanding the\u003cbr\u003esupersonic (with M\u003csmall\u003ep\u003c/small\u003e～1 where M\u003csmall\u003ep\u003c/small\u003e is the poloidal Mach number) plasma\u003cbr\u003eflows in tokamak H-mode plasmas. Therefore many related theoretical\u003cbr\u003e studies have been made.\u003cbr /\u003e  To study this problem experimentally is to compare poloidal flux on\u003cbr\u003e the inside and outside of the magnetic surfaces.  In the poloidal rotation\u003cbr\u003emeasurements in many tokamaks, the poloidal rotation velocities only in\u003cbr\u003e the outside were measured, since it is difficult to install the observation\u003cbr\u003echords viewing vertically the inside of the torus.  Another severe\u003cbr\u003edifficulty is the calibration of mechanical wavelength offset～0.5 Å) of \u003cbr\u003espectrometers with the accuracy for the plasma rotation measurements.\u003cbr\u003e  The study of the inside/outside asymmetry of poloidal rotation velocity requires\u003cbr\u003e the accuracy of absolute wavelength of ～0.01 Å.  To measure\u003cbr\u003e the absolute value of the rotation velocity canceling this offset, it needs\u003cbr\u003ethe observation along opposite viewing directions.  In past plasma rotation\u003cbr\u003emeasurements using the observation from one direction only, some\u003cbr\u003eassumptions or approximations about the plasma rotation velocity profiles\u003cbr\u003ewere used.  For example, the average of the poloidal rotation velocities in\u003cbr\u003e the inside and the outside was used as poloidal rotation \u0027velocity\u0027 in\u003cbr\u003e Heliotron E.\u003cbr /\u003e  In the present work, I have carried out the measurement of the profiles\u003cbr\u003e of the poloidal rotation velocity, the temperature and the density of \u003cbr\u003eimpurity ions using bidirectional charge exchange spectroscopy (CXS) in\u003cbr\u003ethe Compact Helical System (CHS).  For the purpose mentioned above, this\u003cbr\u003emeasurement system uses two fiber arrays to view vertically the beam\u003cbr\u003e line from up and down sides simultaneously at one vertically elongated\u003cbr\u003esection.  In Heliotron/Torsatron devices like CHS, the strong parallel\u003cbr\u003eviscosity reduces the parallel ion flow velocity which is necessary for\u003cbr\u003e incompressible flow conservation when the perpendicular ion flow exists\u003cbr\u003e in low aspect ratio tori.  This damping is strong in peripheral region\u003cbr\u003ewhere the helical ripple becomes large.  However, the poloidal rotation of\u003cbr\u003e impurity tons mainly driven by radial electric field determined by the\u003cbr\u003eambipolar condition of the electron and ion fluxes is also large in this \u003cbr\u003eperipheral region.  Therefore the compensation of the asymmetry of\u003cbr\u003einside and outside perpendicular flows by the parallel flows becomes\u003cbr\u003edifficult in this region.  When the electrostatic potential is the surface\u003cbr\u003equantity and the poloial rotation of ions is mainly the E×B drift, the\u003cbr\u003e flow, especially of the impurity ions having low pressure, should be\u003cbr\u003e compressible.  Otherwise the electrostatic potential is not the surface\u003cbr\u003equantity or the poloidal rotation of impurity ions is not E × B drift. \u003cbr\u003e  Investigating this problem is easier in low aspect ratio devices.  Therefore\u003cbr\u003ethis measurement in CHS with the lowest aspect ratio R\u003csmall\u003e0\u003c/small\u003e/a=5 in helical\u003cbr\u003edevices will give the new information about the plasma rotations.\u003cbr /\u003e  The preliminary measurements of plasma rotations using this system\u003cbr\u003eclarified some technical problems in multi-channel CXS.  The most\u003cbr\u003eimportant problem was the apparent wavelength shift caused by\u003cbr\u003e the spectral fine structure of hydrogen-like ions used in CXS.  This structure\u003cbr\u003eis the red-side/blue-side asymmetric splitting of the lines due to a \u003cbr\u003erelativistic effect and thus cause the red-side/blue-side asymmetry of the\u003cbr\u003eDoppler broadened spectral profile.  Because of this asymmetry, the\u003cbr\u003e wavelength given by single Gaussian least square fitting shows the\u003cbr\u003e apparent shifts which depends on Doppler widths.  The observed apparent\u003cbr\u003e shifts of CVI lines, not due to plasma rotation, in the plasma peripheral\u003cbr\u003e region (Ti～100eV) and in the after-glow recombining phase (Ti～\u003cbr\u003e30eV) are always red-shifts regardless the direction of plasma rotation. \u003cbr\u003e  The magnitude corresponds to the velocity error of a few km/s.  This\u003cbr\u003edirection and magnitude are consistent with the calculation using the\u003cbr\u003ecollisional l-mixing model.  This value is not negligible in CHS plasmas, \u003cbr\u003eand thus should be corrected.\u003cbr /\u003e  The density profile of the fully ionized impurity ions can be measured\u003cbr\u003eusing the intensity of the charge exchange spectral lines.  For this purpose, \u003cbr\u003ethe initial beam density profile without attenuation was also measured in\u003cbr\u003ethe torus using H α from the beam.  The measured density profile was a\u003cbr\u003ebroad and inside shifted profile compared with the calculated one.  This\u003cbr\u003eresult means the possibility to measure the parameters on inside of the\u003cbr\u003e torus with CXS.  However, the calculation of the beam attenuation\u003cbr\u003erequired that the average electron densities should be less than 2 ×\u003cbr\u003e10\u003csup\u003e13\u003c/sup\u003e cm\u003csup\u003e-3\u003c/sup\u003e to avoid the ambiguity of beam attenuation calculation and the\u003cbr\u003e degradation of signal level on the inside.\u003cbr /\u003e  The measurements of the asymmetry of the poloidal flux of fully\u003cbr\u003e ionized carbon tons on the inside and outside of the torus were carried\u003cbr\u003e out for the magnetic surface configurations with different magnetic axis\u003cbr\u003e positions.  In inward shifted configurations, the gradients of surface\u003cbr\u003e function (dψ/dR) on the inside and outside of the section are almost\u003cbr\u003e symmetric.  It becomes asymmetric in outward shifted configurations\u003cbr\u003e and the strength of the radial electric field will become asymmetric in\u003cbr\u003e these configuration.\u003cbr /\u003e  The asymmetry of the Doppler shifts of the CVI line(\u0026Delta;n=8-7, λ\u003cbr\u003e=5290 Å) on the inside and outside of the torus was successfully \u003cbr\u003emeasured.  In outward shifted configurations, the electrostatic potential\u003cbr\u003e calculated from this velocity using the momentum balance equation is the\u003cbr\u003e surface quantity.  The measured density of impurity ions has a hollow\u003cbr\u003e profile and is higher on the inside of the magnetic surfaces compared\u003cbr\u003e with that on the outside.  This inside/outside asymmetry of the density profile\u003cbr\u003e can be explained by the poloidal flow conservation on both sides\u003cbr\u003e under the damping of toroidal rotation.\u003cbr /\u003e　　　In the inward shifted configurations, the density profile is a flat or\u003cbr\u003epeaking profile and the inside/outside asymmetry is not clear.  The\u003cbr\u003equantitative comparison or the electrostatic potential and the poloidal flow\u003cbr\u003e on both sides is difficult in inward shifted configurations because of\u003cbr\u003ethe intense back and radiation at the inside of the magnetic axis.  It\u003cbr\u003ecauses the degradation of signal/noise ratio of spectrum after subtracting\u003cbr\u003ebackground spectrum.  However, this change in the density asymmetry is\u003cbr\u003econsistent with the past measurement of the toroidal rotation damping and\u003cbr\u003esuggests the poloidal rotation accompanying the inside/outside asymmetric\u003cbr\u003etoroidal flow.  Therefore the measurement of inside/outside asymmetry of\u003cbr\u003e the toroidal rotation velocity is an interesting future theme.", "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322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": "1997"}]}, "item_1_text_20": {"attribute_name": "業務メモ", "attribute_value_mlt": [{"subitem_text_value": "（2018年2月9日）本籍など個人情報の記載がある旧要旨・審査要旨を個人情報のない新しいものに差し替えた。承諾書等未確認。要確認該当項目修正のこと。"}]}, "item_creator": {"attribute_name": "著者", "attribute_type": "creator", "attribute_value_mlt": [{"creatorNames": [{"creatorName": "NISHIMURA, Shin", "creatorNameLang": "en"}], "nameIdentifiers": [{"nameIdentifier": "8575", "nameIdentifierScheme": "WEKO"}]}]}, "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", "download_preview_message": "", "file_order": 0, "filename": "甲322_要旨.pdf", "filesize": [{"value": "384.3 kB"}], "format": "application/pdf", "future_date_message": "", "is_thumbnail": false, "licensetype": "license_11", "mimetype": "application/pdf", "size": 384300.0, "url": {"label": "要旨・審査要旨 / Abstract, Screening Result", "url": "https://ir.soken.ac.jp/record/464/files/甲322_要旨.pdf"}, "version_id": "acb09859-3027-45c6-92c2-b9356e39f01b"}, {"accessrole": "open_date", "date": [{"dateType": "Available", "dateValue": "2016-02-17"}], "displaytype": "simple", "download_preview_message": "", "file_order": 1, "filename": "甲322_本文.pdf", "filesize": [{"value": "8.2 MB"}], "format": "application/pdf", "future_date_message": "", "is_thumbnail": false, "licensetype": "license_11", "mimetype": "application/pdf", "size": 8199999.999999999, "url": {"label": "本文", "url": "https://ir.soken.ac.jp/record/464/files/甲322_本文.pdf"}, "version_id": "8a953942-a466-4e4a-9cd3-1f7d3814b380"}]}, "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": "Observation of the Non-uniform Poloidal Flow of Impurity Ion on Magnetic Surfaces using Bidirectional Charge Exchange Spectroscopy in CHS", "item_titles": {"attribute_name": "タイトル", "attribute_value_mlt": [{"subitem_title": "Observation of the Non-uniform Poloidal Flow of Impurity Ion on Magnetic Surfaces using Bidirectional Charge Exchange Spectroscopy in CHS"}, {"subitem_title": "Observation of the Non-uniform Poloidal Flow of Impurity Ion on Magnetic Surfaces using Bidirectional Charge Exchange Spectroscopy in CHS", "subitem_title_language": "en"}]}, "item_type_id": "1", "owner": "1", "path": ["12"], "permalink_uri": "https://ir.soken.ac.jp/records/464", "pubdate": {"attribute_name": "公開日", "attribute_value": "2010-02-22"}, "publish_date": "2010-02-22", "publish_status": "0", "recid": "464", "relation": {}, "relation_version_is_last": true, "title": ["Observation of the Non-uniform Poloidal Flow of Impurity Ion on Magnetic Surfaces using Bidirectional Charge Exchange Spectroscopy in CHS"], "weko_shared_id": 1}