{"created":"2025-02-21T03:17:54.851697+00:00","id":2006326,"links":{},"metadata":{"_buckets":{"deposit":"5864e2e7-ac44-449e-ac4e-7bc02ef2a024"},"_deposit":{"created_by":41,"id":"2006326","owners":[41],"pid":{"revision_id":0,"type":"depid","value":"2006326"},"status":"published"},"_oai":{"id":"oai:hiroshima.repo.nii.ac.jp:02006326","sets":["1730444907710"]},"author_link":[],"item_1617186331708":{"attribute_name":"Title","attribute_value_mlt":[{"subitem_title":"Efficiency Crisis of Swift Gamma-Ray Bursts with Shallow X-ray Afterglows : Prior Activity or Time-Dependent Microphysics?","subitem_title_language":"en"}]},"item_1617186419668":{"attribute_name":"Creator","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{"creatorName":"Ioka, Kunihito","creatorNameLang":"en"}],"familyNames":[{"familyName":"Ioka","familyNameLang":"en"}],"givenNames":[{"givenName":"Kunihito","givenNameLang":"en"}]},{"creatorNames":[{"creatorName":"Toma, Kenji","creatorNameLang":"en"}],"familyNames":[{"familyName":"Toma","familyNameLang":"en"}],"givenNames":[{"givenName":"Kenji","givenNameLang":"en"}]},{"creatorNames":[{"creatorName":"Yamazaki, Ryo","creatorNameLang":"en"}],"familyNames":[{"familyName":"Yamazaki","familyNameLang":"en"}],"givenNames":[{"givenName":"Ryo","givenNameLang":"en"}]},{"creatorNames":[{"creatorName":"Nakamura, Takashi","creatorNameLang":"en"}],"familyNames":[{"familyName":"Nakamura","familyNameLang":"en"}],"givenNames":[{"givenName":"Takashi","givenNameLang":"en"}]}]},"item_1617186476635":{"attribute_name":"Access Rights","attribute_value_mlt":[{"subitem_access_right":"open access","subitem_access_right_uri":"http://purl.org/coar/access_right/c_abf2"}]},"item_1617186609386":{"attribute_name":"Subject","attribute_value_mlt":[{"subitem_subject":"440","subitem_subject_scheme":"NDC"}]},"item_1617186626617":{"attribute_name":"Description","attribute_value_mlt":[{"subitem_description":"Most X-ray afterglows of gamma-ray bursts (GRBs) observed by the Swift satellite have a shallow decay phase t-1/2 in the first thousands of seconds. We discuss that the shallow decay requires an unreasonably high gamma-ray efficiency, 75-90%, within current models, which is difficult to be produced by internal shocks. Such a crisis may be avoided if a weak relativistic explosion occurs ～ 103-106 s prior to the main burst or if the energy fraction that goes into electrons increases during the shallow decay, e t1/2. The former model predicts a very long precursor while either model would prefer dim optical flashes from the reverse shock as recently reported.","subitem_description_language":"en"}]},"item_1617186643794":{"attribute_name":"Publisher","attribute_value_mlt":[{"subitem_publisher":"EDP Sciences"}]},"item_1617186702042":{"attribute_name":"Language","attribute_value_mlt":[{"subitem_language":"eng"}]},"item_1617186920753":{"attribute_name":"Source Identifier","attribute_value_mlt":[{"subitem_source_identifier":"0004-6361","subitem_source_identifier_type":"ISSN"},{"subitem_source_identifier":"AA00553195","subitem_source_identifier_type":"NCID"}]},"item_1617187024783":{"attribute_name":"Page Start","attribute_value_mlt":[{"subitem_start_page":"7"}]},"item_1617187056579":{"attribute_name":"Bibliographic Information","attribute_value_mlt":[{"bibliographicIssueDates":{"bibliographicIssueDate":"2006-10","bibliographicIssueDateType":"Issued"},"bibliographicIssueNumber":"1","bibliographicPageEnd":"12","bibliographicPageStart":"7","bibliographicVolumeNumber":"458","bibliographic_titles":[{"bibliographic_title":"Astronomy and Astrophysics"},{"bibliographic_title":"Astronomy and Astrophysics"}]}]},"item_1617258105262":{"attribute_name":"Resource Type","attribute_value_mlt":[{"resourcetype":"journal article","resourceuri":"http://purl.org/coar/resource_type/c_6501"}]},"item_1617265215918":{"attribute_name":"Version Type","attribute_value_mlt":[{"subitem_version_resource":"http://purl.org/coar/version/c_b1a7d7d4d402bcce","subitem_version_type":"AO"}]},"item_1617353299429":{"attribute_name":"Relation","attribute_value_mlt":[{"subitem_relation_type_id":{"subitem_relation_type_id_text":"10.1051/0004-6361:20064939","subitem_relation_type_select":"DOI"}},{"subitem_relation_type":"isVersionOf","subitem_relation_type_id":{"subitem_relation_type_id_text":"http://dx.doi.org/10.1051/0004-6361:20064939","subitem_relation_type_select":"DOI"}}]},"item_1617605131499":{"attribute_name":"File","attribute_type":"file","attribute_value_mlt":[{"accessrole":"open_access","date":[{"dateType":"Available","dateValue":"2023-03-18"}],"displaytype":"simple","filename":"AstronAstrophy_458_7.pdf","filesize":[{"value":"118.0 KB"}],"mimetype":"application/pdf","url":{"objectType":"fulltext","url":"https://hiroshima.repo.nii.ac.jp/record/2006326/files/AstronAstrophy_458_7.pdf"},"version_id":"8e98f238-4868-4478-b27e-02340493a00d"}]},"item_1732771732025":{"attribute_name":"旧ID","attribute_value":"17235"},"item_title":"Efficiency Crisis of Swift Gamma-Ray Bursts with Shallow X-ray Afterglows : Prior Activity or Time-Dependent Microphysics?","item_type_id":"40003","owner":"41","path":["1730444907710"],"pubdate":{"attribute_name":"PubDate","attribute_value":"2023-03-18"},"publish_date":"2023-03-18","publish_status":"0","recid":"2006326","relation_version_is_last":true,"title":["Efficiency Crisis of Swift Gamma-Ray Bursts with Shallow X-ray Afterglows : Prior Activity or Time-Dependent Microphysics?"],"weko_creator_id":"41","weko_shared_id":-1},"updated":"2025-02-21T07:20:00.944490+00:00"}