{"created":"2023-05-15T14:36:25.484246+00:00","id":46902,"links":{},"metadata":{"_buckets":{"deposit":"67f7eb2e-ad25-4bc3-aed1-f37db82966fa"},"_deposit":{"created_by":1,"id":"46902","owners":[1],"pid":{"revision_id":0,"type":"depid","value":"46902"},"status":"published"},"_oai":{"id":"oai:repo.qst.go.jp:00046902","sets":["1"]},"author_link":["468036","468035","468039","468038","468034","468042","468040","468041","468037"],"item_8_biblio_info_7":{"attribute_name":"書誌情報","attribute_value_mlt":[{"bibliographicIssueDates":{"bibliographicIssueDate":"2013-09","bibliographicIssueDateType":"Issued"},"bibliographicIssueNumber":"17","bibliographicPageEnd":"6064","bibliographicPageStart":"6047","bibliographicVolumeNumber":"58","bibliographic_titles":[{"bibliographic_title":"PHYSICS IN MEDICINE AND BIOLOGY"}]}]},"item_8_description_5":{"attribute_name":"抄録","attribute_value_mlt":[{"subitem_description":"A beam delivery system using a single-radius-beam-wobbling method has been used to form a conformal irradiation field for proton radiotherapy in Japan. A proton beam broadened by the beam-wobbling system provides a non-Gaussian distribution of projection angle different in two mutually orthogonal planes with a common beam central axis, at a certain position. However, the conventional initial beam model for dose calculations has been using an approximation of symmetric Gaussian angular distribution with the same variance in both planes (called here a Gaussian model with symmetric\nvariance (GMSV)), instead of the accurate one. We have developed a more\naccurate initial beam model defined as a non-Gaussian model with asymmetric variance (NonGMAV), and applied it to dose calculations using the simplified Monte Carlo (SMC) method. The initial beam model takes into account the different distances of two beam-wobbling magnets from the iso-center and also the different amplitudes of kick angle given by each magnet. We have confirmed that the calculation using the SMC with NonGMAV reproduced the measured dose distribution formed in air by a mono-energetic proton beam passing through a square aperture collimator better than with the GMSV and with a Gaussian model with asymmetric variance (GMAV) in which different variances of angular distributions are used in the two mutually orthogonal\nplanes. Measured dose distributions in a homogeneous phantom formed by a\nmodulated proton beam passing through a range shifter and an L-shaped range compensator, were consistent with calculations using the SMC with GMAV and NonGMAV, but in disagreement with calculations using the SMC with GMSV. Measured lateral penumbrae in a lateral direction were reproduced better by calculations using the SMC with NonGMAV than by those with GMAV, when an aperture collimator with a smaller opening was used. We found that such a difference can be attributed to the non-Gaussian angular distribution of the initial beam at a lateral position for the beam-wobbling system. Calculations using the SMC with NonGMAV are effective to reproduce dose distributions formed by a beam-wobbling system more accurately than that with GMSV or that with GMAV. ","subitem_description_type":"Abstract"}]},"item_8_publisher_8":{"attribute_name":"出版者","attribute_value_mlt":[{"subitem_publisher":"IOP Publishing "}]},"item_8_relation_14":{"attribute_name":"DOI","attribute_value_mlt":[{"subitem_relation_type_id":{"subitem_relation_type_id_text":"10.1088/0031-9155/58/17/6047","subitem_relation_type_select":"DOI"}}]},"item_8_relation_17":{"attribute_name":"関連サイト","attribute_value_mlt":[{"subitem_relation_name":[{"subitem_relation_name_text":"http://iopscience.iop.org/0031-9155/58/17/6047/article"}],"subitem_relation_type_id":{"subitem_relation_type_id_text":"http://iopscience.iop.org/0031-9155/58/17/6047/article","subitem_relation_type_select":"URI"}}]},"item_8_source_id_9":{"attribute_name":"ISSN","attribute_value_mlt":[{"subitem_source_identifier":"0031-9155","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":"Tansho, Ryohei"}],"nameIdentifiers":[{"nameIdentifier":"468034","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"Takada, Yoshihisa"}],"nameIdentifiers":[{"nameIdentifier":"468035","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"Kohno, Ryosuke"}],"nameIdentifiers":[{"nameIdentifier":"468036","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"Hotta, Kenji"}],"nameIdentifiers":[{"nameIdentifier":"468037","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"Hara, Yousuke"}],"nameIdentifiers":[{"nameIdentifier":"468038","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"et.al"}],"nameIdentifiers":[{"nameIdentifier":"468039","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"丹正 亮平","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"468040","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"高田 義久","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"468041","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"原 洋介","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"468042","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":"Experimental verification of dose calculation using the simplified Monte Carlo method with an improved initial beam model for a beam-wobbling system","item_titles":{"attribute_name":"タイトル","attribute_value_mlt":[{"subitem_title":"Experimental verification of dose calculation using the simplified Monte Carlo method with an improved initial beam model for a beam-wobbling system"}]},"item_type_id":"8","owner":"1","path":["1"],"pubdate":{"attribute_name":"公開日","attribute_value":"2014-11-06"},"publish_date":"2014-11-06","publish_status":"0","recid":"46902","relation_version_is_last":true,"title":["Experimental verification of dose calculation using the simplified Monte Carlo method with an improved initial beam model for a beam-wobbling system"],"weko_creator_id":"1","weko_shared_id":-1},"updated":"2023-05-15T23:46:15.111198+00:00"}