{"_buckets": {"deposit": "abfb0585-bddd-4110-86a0-53d6c8ecdb0d"}, "_deposit": {"created_by": 1, "id": "510", "owners": [1], "pid": {"revision_id": 0, "type": "depid", "value": "510"}, "status": "published"}, "_oai": {"id": "oai:ir.soken.ac.jp:00000510", "sets": ["12"]}, "author_link": ["8684", "8686", "8685"], "item_1_biblio_info_21": {"attribute_name": "書誌情報（ソート用）", "attribute_value_mlt": [{"bibliographicIssueDates": {"bibliographicIssueDate": "2004-03-24", "bibliographicIssueDateType": "Issued"}, "bibliographic_titles": [{}]}]}, "item_1_creator_2": {"attribute_name": "著者名", "attribute_type": "creator", "attribute_value_mlt": [{"creatorNames": [{"creatorName": "松本, 新功"}], "nameIdentifiers": [{"nameIdentifier": "8684", "nameIdentifierScheme": "WEKO"}]}]}, "item_1_creator_3": {"attribute_name": "フリガナ", "attribute_type": "creator", "attribute_value_mlt": [{"creatorNames": [{"creatorName": "マツモト, ヨシカツ"}], "nameIdentifiers": [{"nameIdentifier": "8685", "nameIdentifierScheme": "WEKO"}]}]}, "item_1_date_granted_11": {"attribute_name": "学位授与年月日", "attribute_value_mlt": [{"subitem_dategranted": "2004-03-24"}]}, "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": "2004026", "subitem_description_type": "Other"}]}, "item_1_description_12": {"attribute_name": "要旨", "attribute_value_mlt": [{"subitem_description": "　　Beams of hydrogen and deuterium negative ions are used for plasma heating by a neutral beam injection for thermo-nuclear fusion experiments. Volume-type negative ion sources are utilized in experiment of large fusion devices in Japan such as the large helical device (LHD) and JT-60. For development of high efficient H\u003cSUP\u003e-\u003c/SUP\u003e ion sources, H\u003cSUP\u003e-\u003c/SUP\u003e production and transport mechanism in extraction resion of ion sources should be investigated.\u003cbr /\u003e  For H\u003cSUP\u003e-\u003c/SUP\u003e density and velocity measurement in an ion source plasma, the laser- photodetachment method with Langmuir probe (PD-LP) has been widely used. Since the distributions of H\u003cSUP\u003e-\u003c/SUP\u003e density and H\u003cSUP\u003e-\u003c/SUP\u003e velocity inside ion sources can be obtained from this method, these parameters are useful to study the negative ion production mechanism and the extraction modeling. However it is difficult to construct an exact model for beam extraction based on the photodetachment method with a PD-LP. Therefore H\u003cSUP\u003e-\u003c/SUP\u003e transport mechanism in ion sources has been studied with numerical analysis mainly, because there is no experimental method to measure the relation of H\u003cSUP\u003e-\u003c/SUP\u003e ions inside and extracted from ion sources. Another experimental method suitable to study the negative ion transport in an ion source is desirable.\u003cbr /\u003e\u003cbr /\u003e　　In this thesis, a new diagnostic method, laser aided H\u003cSUP\u003e-\u003c/SUP\u003e beam current measurement (PD-FC： photodetachment method with Faraday cup), is developed and utilized to study the H\u003cSUP\u003e-\u003c/SUP\u003e transport inside an H\u003cSUP\u003e-\u003c/SUP\u003e ion source. This method consists of the followings, (1) A pulsed laser beam is irradiated into the plasma, the photodetachment reaction (H\u003cSUP\u003e-\u003c/SUP\u003e＋hv → H ＋e\u003cSUP\u003e-\u003c/SUP\u003e) occurs along the laser beam. (2) Steady state transport of H\u003cSUP\u003e-\u003c/SUP\u003e is hindered by localized depletion of H\u003cSUP\u003e-\u003c/SUP\u003e, and the change in the extracted H\u003cSUP\u003e-\u003c/SUP\u003e current is detected by a Faraday cup. The detected change in the H\u003cSUP\u003e-\u003c/SUP\u003e current should include information on the H\u003cSUP\u003e-\u003c/SUP\u003e density, the velocity, and the transport. It can be also applicable to a strongly magnetized plasma as it directly detects negative ions. In this thesis, the H\u003cSUP\u003e-\u003c/SUP\u003e transport near the plasma electrode (PH) inside the plasma is studied using both the conventional method with PD-LP and the new method.\u003cbr /\u003e\u003cbr /\u003e　　This thesis consists of 7 chapters. The background of this study, principle of measurement, and the extperimental setup for this study are described in chapter 1, 2, and 3, respectively. Chapter 4, 5, and 6 are for the experimental results and discussion. The new diagnostic method is applied to a compact negative ion source, and three experimental studies have been carried out depending on the distance between the PE and the laser beam axis, defined as D, and on whether Cs vapor is added or not.\u003cbr /\u003e\u003cbr /\u003e　　In chapter 4, the time evolution of H\u003cSUP\u003e-\u003c/SUP\u003e beam current was analyzed in the case of D＝0, where the laser beam with semicircular cross section passes the region right front of the beam extraction aperture contacting with PE. The decrease of H\u003cSUP\u003e-\u003c/SUP\u003e beam current after photodetachment, △I\u003cSUB\u003eH\u003c/SUB\u003e-, becomes larger as the laser power density is increased. It is confirmed that the laser power is large enough to destruct all the H\u003cSUP\u003e-\u003c/SUP\u003e in the beam path.\u003cbr /\u003e　Next, to study H\u003cSUP\u003e-\u003c/SUP\u003e transport near the extraction hole, the time evolution of H\u003cSUP\u003e-\u003c/SUP\u003e beam current after photodetachment is analyzed on the basis of the ballistic theory. From the recoverv time of H\u003cSUP\u003e-\u003c/SUP\u003e beam current, H\u003cSUP\u003e-\u003c/SUP\u003e velocity is derived, and then H\u003cSUP\u003e-\u003c/SUP\u003e density is estimated from the obtained H\u003cSUP\u003e-\u003c/SUP\u003e velocity. The measured H\u003cSUP\u003e-\u003c/SUP\u003e velocities obtained with both methods agree well, while H\u003cSUP\u003e-\u003c/SUP\u003e density measured with the Faraday cup is larger than that by the Langmuir probe in high gas pressure condition. The reasons for this disagreement are considered to be due to the influence of collision with H\u003cSUB\u003e2\u003c/SUB\u003e. molecules in plasma, because ballistic theory does not hold in high gas pressure condition.\u003cbr /\u003e\u003cbr /\u003e　　In chapter 5, the characteristics of H\u003cSUP\u003e-\u003c/SUP\u003e beam current after photodetachment with D\u003e0 are discussed. Here we cannot adopt the ballistic theory used in chapter 4, because in the experimental conditions the shortest mean-free-path and the Larmor radius are both comparable to D. Therefore we must treat collisions of H\u003cSUP\u003e-\u003c/SUP\u003e ions with other ions, electrons, atoms, and molecules, and the gyro motions during the travel of H\u003cSUP\u003e-\u003c/SUP\u003e ions from the plasma to the extraction hole of PE. This situation is simulated by the Monte-Carlo method. The calculated results are compared with the experimental results, and then we can make sure whether the transport model is valid or not.\u003cbr /\u003e　The maximum change of H\u003cSUP\u003e-\u003c/SUP\u003e current after photodetachmemt (△I\u003cSUB\u003eH\u003c/SUB\u003e-\u003cSUB\u003emax\u003c/SUB\u003e) decreases gradually as D increases. At D\u003e15mm the signal of △I\u003cSUB\u003eH\u003c/SUB\u003e-\u003cSUB\u003emax\u003c/SUB\u003e was too small to distinguish it from the plasma noise. In the plasma used here, we found that the H\u003cSUP\u003e-\u003c/SUP\u003e ions in the region within 15 mm from the PE contributed for H\u003cSUP\u003e-\u003c/SUP\u003e beam. This tendency is in good agreement with the simulation results, and therefore it is concluded that the presernt H\u003cSUP\u003e-\u003c/SUP\u003e transport model is reasonable in a compact negative ion source of this size.\u003cbr /\u003e　It is found that the sheath potential at PE affects the amount and time behavior of PD-FC signal. Because the kinetic energy is smaller than the typically formed negative sheath potential on the wall, H\u003cSUP\u003e-\u003c/SUP\u003e is reflected on the surface of PE. Then some part of extracted beam consists of these reflected ions, which is observed as a tail in PD-FC signal wave form. When the sheath potential is reversed by adjusting the PE bias voltage (V\u003cSUB\u003eb\u003c/SUB\u003e) against plasma potential (V\u003cSUB\u003ep\u003c/SUB\u003e), H\u003cSUP\u003e-\u003c/SUP\u003e becomes hitting PE and does not survive. As a result of experiment, the tail was vanished in the PD-FC signal with V\u003cSUB\u003ep\u003c/SUB\u003e＜V\u003cSUB\u003eb\u003c/SUB\u003e condition. This change of wave form is also demonstrated by Monte-Carlo calculation which takes the destruction of H\u003cSUP\u003e-\u003c/SUP\u003e ions on the PE surface into consideration. For high extraction efficiency of H\u003cSUP\u003e-\u003c/SUP\u003e ions from ion sources, a PE should be biased lower than plasma potential to prevent H\u003cSUP\u003e-\u003c/SUP\u003e ions from being destructed by collision with a PE. \u003cbr /\u003e\u003cbr /\u003e　　It is widely known that addition of Cs into volume type negative ion sources make increase of extracted H\u003cSUP\u003e-\u003c/SUP\u003e beam current. In chapter 6, to clear the cause of this Cs effect, the same experimental method as in chapter 5 is applied for cesium added hydrogen plasma. By introducing Cs vapor, the extracted H\u003cSUP\u003e-\u003c/SUP\u003e current increases by factor of 2.5. At D～2 mm, △I\u003cSUB\u003eH\u003c/SUB\u003e-\u003cSUB\u003emax\u003c/SUB\u003e is also enhanced by 2.5 times. The dependence of △I\u003cSUB\u003eH\u003c/SUB\u003e-\u003cSUB\u003emax\u003c/SUB\u003e. upon D shows that the increase of H\u003cSUP\u003e-\u003c/SUP\u003e near the PE contributes to the enhancement of extracted beam in the case of Cs added plasma, which suggests the surface production of H\u003cSUP\u003e-\u003c/SUP\u003e on the grid. \u003cbr /\u003e\u003cbr /\u003e　　In chapter 7, the conclusions are described throughout the studies on the H\u003cSUP\u003e-\u003c/SUP\u003e transport inside the ion source.", "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758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": "2003"}]}, "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": "MATSUMOTO, Yoshikatsu", "creatorNameLang": "en"}], "nameIdentifiers": [{"nameIdentifier": "8686", "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758_要旨.pdf", "filesize": [{"value": "444.8 kB"}], "format": "application/pdf", "future_date_message": "", "is_thumbnail": false, "licensetype": "license_11", "mimetype": "application/pdf", "size": 444800.0, "url": {"label": "要旨・審査要旨 / Abstract, Screening Result", "url": "https://ir.soken.ac.jp/record/510/files/甲758_要旨.pdf"}, "version_id": "2ec6a22f-1a61-4f5e-8dc0-80c411d0c85a"}]}, "item_language": {"attribute_name": "言語", "attribute_value_mlt": [{"subitem_language": "jpn"}]}, "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": "レーザー光脱離反応時のビーム量測定を利用した負イオン源内H\u003cSUP\u003e-\u003c/SUP\u003e輸送の研究", "item_titles": {"attribute_name": "タイトル", "attribute_value_mlt": [{"subitem_title": "レーザー光脱離反応時のビーム量測定を利用した負イオン源内H\u003cSUP\u003e-\u003c/SUP\u003e輸送の研究"}]}, "item_type_id": "1", "owner": "1", "path": ["12"], "permalink_uri": "https://ir.soken.ac.jp/records/510", "pubdate": {"attribute_name": "公開日", "attribute_value": "2010-02-22"}, "publish_date": "2010-02-22", "publish_status": "0", "recid": "510", "relation": {}, "relation_version_is_last": true, "title": ["レーザー光脱離反応時のビーム量測定を利用した負イオン源内H\u003cSUP\u003e-\u003c/SUP\u003e輸送の研究"], "weko_shared_id": 1}