{"created":"2023-07-27T06:55:07.352217+00:00","id":50816,"links":{},"metadata":{"_buckets":{"deposit":"12f28e75-97e5-41e1-ad0b-ba5c86f601d8"},"_deposit":{"created_by":18,"id":"50816","owners":[18],"pid":{"revision_id":0,"type":"depid","value":"50816"},"status":"published"},"_oai":{"id":"oai:kanazawa-u.repo.nii.ac.jp:00050816","sets":["2812:2813:2831"]},"author_link":["12380","17600"],"item_9_biblio_info_8":{"attribute_name":"書誌情報","attribute_value_mlt":[{"bibliographicIssueDates":{"bibliographicIssueDate":"2003-03","bibliographicIssueDateType":"Issued"},"bibliographicPageStart":"49p.","bibliographicVolumeNumber":"2001-2002","bibliographic_titles":[{"bibliographic_title":"平成14(2002)年度 科学研究費補助金 基盤研究(C) 研究成果報告書"},{"bibliographic_title":"2002 Fiscal Year Final Research Report","bibliographic_titleLang":"en"}]}]},"item_9_creator_33":{"attribute_name":"著者別表示","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{}],"nameIdentifiers":[{},{}]}]},"item_9_description_21":{"attribute_name":"抄録","attribute_value_mlt":[{"subitem_description":"1GWを越える高出力電磁波源では,高出力に伴う強電場による放電破壊現象が起こる.これに対処する一つの方法が電磁波放射の短パルス化である.近年,超放射と呼ばれる新しい電磁波放射機構が提唱されている.この機構は元来パルス的にしか起きず,しかも放射の効率が良い事が特徴である.これを高出力電磁波源として用いるためには,超短パルスの大強度電子ビームが必要とされる.更に実用化に向けて繰り返し運転の可能性を確かめる必要がある.本研究では,大強度相対論的電子ビームに外部電源を用いずに変調をかける新たな方式を開発し,これを用いて繰り返し超放射の予備的実験い成功した.\n同軸空洞をのみ用いて大強度電子ビームに変調をかける自動変調方式では,従来は同長の空洞を使用していた.しかし,この方式では,電流立ち上がり時間の遅い電子ビームに,高周波の変調をかけることはできなかった.本研究では,初段の空洞の長さを,ビーム電流立ち上がり時間に光速をかけた長さの1/3以上に設定し,所望の変調周期に対応する空洞長まで段快適に空洞長を半分にして行く多段自動変調方式の開発に成功した.具体的には500keV,4kA,パルス幅12nsの電子ビームに1GHzの変調をかけることに成功した.\n変調周波数500MHzの電子ビームを,サイクロトロン超放射の条件を満たす環境に入射した所,変調周期に対応した間隔で,ビーム幅と同程度の間の電磁波放射を観測した.放射電磁波の周波数は期待通りの17GHzであった.この結果は,超放射の繰り返し運転の可能性を示したものと考えられる.この放射が確実に超放射機構と断定するためには,今後,電磁波出力の電流依存性等を調べる必要がある.","subitem_description_type":"Abstract"},{"subitem_description":"It was observed that the length of a coaxial cavity strongly affects the induced gap voltage and the level of automodulation. For high-frequency automodulation for a beam with slow rise time, a series of coaxial cavities with decreasing lengths named multi-stage automodulation was useful.\nHighly modulated intense eletron beams with modulated frequency around 1 GHz were obtained by the multi-stage automodulation scheme from an intense electron beam with energy of 500 keV, current of 4 kA, duration of 12 ns and rise time of 6 ns. Criteria for the cavity lengths are proposed. The round trip time for electromagnetic wave of the first cavity must be larger than the 1/3 of the current rise time. The lengths of the following cavities are set to the half stage by stage. The round trip time of the last cavity must be set to the half of the desired modulation period.\nTrains of pulsed microwaves with period of 2 ns which corresponded to the modulated period of an elctron beam were observed. The radiated microwave frequency was around 17 GHz that was reasonable for cyclotron superradience. These results suggest that the cyclotron superradiance can be repeated with a modulated intense electron beam. The dependence of the output power on the beam current should be investigated.","subitem_description_type":"Abstract"}]},"item_9_description_22":{"attribute_name":"内容記述","attribute_value_mlt":[{"subitem_description":"研究課題/領域番号:13680553, 研究期間(年度):2001-2002","subitem_description_type":"Other"},{"subitem_description":"出典：「多段自動変調された大強度相対論的電子ビームからの超放射」研究成果報告書　課題番号13680553\n  (KAKEN：科学研究費助成事業データベース（国立情報学研究所）)\n　　　本文データは著者版報告書より作成","subitem_description_type":"Other"}]},"item_9_description_5":{"attribute_name":"提供者所属","attribute_value_mlt":[{"subitem_description":"金沢大学理工研究域数物科学系","subitem_description_type":"Other"}]},"item_9_identifier_registration":{"attribute_name":"ID登録","attribute_value_mlt":[{"subitem_identifier_reg_text":"10.24517/00057124","subitem_identifier_reg_type":"JaLC"}]},"item_9_relation_28":{"attribute_name":"関連URI","attribute_value_mlt":[{"subitem_relation_name":[{"subitem_relation_name_text":"https://kaken.nii.ac.jp/search/?qm=90143875"}],"subitem_relation_type_id":{"subitem_relation_type_id_text":"https://kaken.nii.ac.jp/search/?qm=90143875","subitem_relation_type_select":"URI"}},{"subitem_relation_name":[{"subitem_relation_name_text":"https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13680553/"}],"subitem_relation_type_id":{"subitem_relation_type_id_text":"https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13680553/","subitem_relation_type_select":"URI"}},{"subitem_relation_name":[{"subitem_relation_name_text":"https://kaken.nii.ac.jp/report/KAKENHI-PROJECT-13680553/136805532002kenkyu_seika_hokoku_gaiyo/"}],"subitem_relation_type_id":{"subitem_relation_type_id_text":"https://kaken.nii.ac.jp/report/KAKENHI-PROJECT-13680553/136805532002kenkyu_seika_hokoku_gaiyo/","subitem_relation_type_select":"URI"}}]},"item_9_version_type_25":{"attribute_name":"著者版フラグ","attribute_value_mlt":[{"subitem_version_resource":"http://purl.org/coar/version/c_ab4af688f83e57aa","subitem_version_type":"AM"}]},"item_files":{"attribute_name":"ファイル情報","attribute_type":"file","attribute_value_mlt":[{"accessrole":"open_date","date":[{"dateType":"Available","dateValue":"2021-05-14"}],"displaytype":"detail","filename":"SC-PR-KAMATA-K-kaken 2003-49p.pdf","filesize":[{"value":"8.0 MB"}],"format":"application/pdf","licensetype":"license_11","mimetype":"application/pdf","url":{"label":"SC-PR-KAMATA-K-kaken 2003-49p.pdf","url":"https://kanazawa-u.repo.nii.ac.jp/record/50816/files/SC-PR-KAMATA-K-kaken 2003-49p.pdf"},"version_id":"9a4d0ad4-c80e-4bcf-9f5d-8076a46cecf2"}]},"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":"research report","resourceuri":"http://purl.org/coar/resource_type/c_18ws"}]},"item_title":"多段自動変調された大強度相対論的電子ビームからの超放射","item_titles":{"attribute_name":"タイトル","attribute_value_mlt":[{"subitem_title":"多段自動変調された大強度相対論的電子ビームからの超放射"},{"subitem_title":"Experimental Observation of Superradiance from an Automodulated Intense Relativistic Electron Beam","subitem_title_language":"en"}]},"item_type_id":"9","owner":"18","path":["2831"],"pubdate":{"attribute_name":"公開日","attribute_value":"2021-05-14"},"publish_date":"2021-05-14","publish_status":"0","recid":"50816","relation_version_is_last":true,"title":["多段自動変調された大強度相対論的電子ビームからの超放射"],"weko_creator_id":"18","weko_shared_id":-1},"updated":"2023-07-27T14:40:15.343613+00:00"}