{"created":"2023-05-15T14:37:21.292529+00:00","id":48170,"links":{},"metadata":{"_buckets":{"deposit":"7d1d60f6-0fee-4044-920d-85a0e69f5b9b"},"_deposit":{"created_by":1,"id":"48170","owners":[1],"pid":{"revision_id":0,"type":"depid","value":"48170"},"status":"published"},"_oai":{"id":"oai:repo.qst.go.jp:00048170","sets":["1"]},"author_link":["483835","483837","483838","483836","483831","483832","483834","483833"],"item_8_biblio_info_7":{"attribute_name":"書誌情報","attribute_value_mlt":[{"bibliographicIssueDates":{"bibliographicIssueDate":"2017-03","bibliographicIssueDateType":"Issued"},"bibliographicPageEnd":"1660218-10","bibliographicPageStart":"1660218-1","bibliographicVolumeNumber":"44","bibliographic_titles":[{"bibliographic_title":"International Journal of Modern Physics"}]}]},"item_8_description_5":{"attribute_name":"抄録","attribute_value_mlt":[{"subitem_description":"In heavy ion radiotherapy, ionization chambers are regarded as a standard for determining the absorbed dose given to patient. In ion dosimetry, it is necessary to correct the radiation quality, which depends on the initial recombination effect. This study reveals the radiation quality dependence of the initial recombination in air in ion dosimetry.\nIonization charge was measured for the beams of proton at 40–160 MeV, carbon at 21–400 MeV/n, and iron at 23.5–500 MeV/n using two identical parallel-plate ionization chambers placed in series along the beam axis. The downstream chamber was used as a monitor operated with a constant applied voltage, while the other chamber was used for recombination measurement by changing the voltage. The ratio of the ionization charge measured by the two ionization chambers showed a linear relationship with the inverse of the voltage in the high-voltage region. The initial recombination factor was estimated by extrapolating the obtained linear relationship to infinite voltage. \nThe extent of the initial recombination was found to increase with decreasing incident energy or increasing atomic number of the beam. This behavior can be explained with an amorphous track structure model: the increase of ionization density in the core region of the track due to decreasing kinetic energy or increasing atomic number leads to denser initial ion production and results in a higher recombination probability. For therapeutic carbon ion beams, the extent of the initial recombination was not constant but changed by 0.6% even in the target region. This tendency was quantitatively well reproduced with the track-structure based initial recombination model, however, the transitional change in the track structure is considered to play an important role for further understanding of the characteristics of the initial recombination.","subitem_description_type":"Abstract"}]},"item_8_publisher_8":{"attribute_name":"出版者","attribute_value_mlt":[{"subitem_publisher":"World Scientific Publishing Co Pte Ltd "}]},"item_8_relation_14":{"attribute_name":"DOI","attribute_value_mlt":[{"subitem_relation_type_id":{"subitem_relation_type_id_text":"10.1142/S2010194516602180","subitem_relation_type_select":"DOI"}}]},"item_8_source_id_9":{"attribute_name":"ISSN","attribute_value_mlt":[{"subitem_source_identifier":" 2010-1945 ","subitem_source_identifier_type":"ISSN"}]},"item_access_right":{"attribute_name":"アクセス権","attribute_value_mlt":[{"subitem_access_right":"metadata only access","subitem_access_right_uri":"http://purl.org/coar/access_right/c_14cb"}]},"item_creator":{"attribute_name":"著者","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{"creatorName":"松藤, 成弘"}],"nameIdentifiers":[{"nameIdentifier":"483831","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"松山, 哲大"}],"nameIdentifiers":[{"nameIdentifier":"483832","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"佐藤, 眞二"}],"nameIdentifiers":[{"nameIdentifier":"483833","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"河野, 俊之"}],"nameIdentifiers":[{"nameIdentifier":"483834","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"松藤 成弘","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"483835","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"松山 哲大","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"483836","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"佐藤 眞二","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"483837","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"河野 俊之","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"483838","nameIdentifierScheme":"WEKO"}]}]},"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":"journal article","resourceuri":"http://purl.org/coar/resource_type/c_6501"}]},"item_title":"Recombination characteristics of therapeutic ion beams on ion chamber dosimetry","item_titles":{"attribute_name":"タイトル","attribute_value_mlt":[{"subitem_title":"Recombination characteristics of therapeutic ion beams on ion chamber dosimetry"}]},"item_type_id":"8","owner":"1","path":["1"],"pubdate":{"attribute_name":"公開日","attribute_value":"2017-07-24"},"publish_date":"2017-07-24","publish_status":"0","recid":"48170","relation_version_is_last":true,"title":["Recombination characteristics of therapeutic ion beams on ion chamber dosimetry"],"weko_creator_id":"1","weko_shared_id":-1},"updated":"2023-05-15T23:31:08.016788+00:00"}