Marlom Ramalho, Jouni Suhonen, Andrei Neacsu, Sabin Stoica
{"title":"利用核壳模型评估二次禁止单跃迁非唯一β衰变的光谱形状","authors":"Marlom Ramalho, Jouni Suhonen, Andrei Neacsu, Sabin Stoica","doi":"10.3389/fphy.2024.1455778","DOIUrl":null,"url":null,"abstract":"Experimental and theoretical studies of <jats:inline-formula><mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"><mml:mi>β</mml:mi></mml:math></jats:inline-formula> electrons (electrons emitted in <jats:inline-formula><mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"><mml:msup><mml:mrow><mml:mi>β</mml:mi></mml:mrow><mml:mrow><mml:mo>−</mml:mo></mml:mrow></mml:msup></mml:math></jats:inline-formula>-decay transitions) and their <jats:inline-formula><mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"><mml:mi>β</mml:mi></mml:math></jats:inline-formula>-electron spectra have recently experienced a rapid expansion. These <jats:inline-formula><mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"><mml:mi>β</mml:mi></mml:math></jats:inline-formula> spectral shapes have been used to study total <jats:inline-formula><mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"><mml:mi>β</mml:mi></mml:math></jats:inline-formula> spectra of fission-product nuclei in the quest for explanation of the reactor-flux anomalies, and individual <jats:inline-formula><mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"><mml:mi>β</mml:mi></mml:math></jats:inline-formula> transitions in search for <jats:inline-formula><mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"><mml:mi>β</mml:mi></mml:math></jats:inline-formula> spectral shapes sensitive to the effective value of the weak axial coupling <jats:inline-formula><mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"><mml:msub><mml:mrow><mml:mi>g</mml:mi></mml:mrow><mml:mrow><mml:mtext>A</mml:mtext></mml:mrow></mml:msub></mml:math></jats:inline-formula>. In the former case the TAGS (total absorption gamma-ray spectroscopy) can be efficiently used to measure the total <jats:inline-formula><mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"><mml:mi>β</mml:mi></mml:math></jats:inline-formula> spectral shapes and in the latter case dedicated measurements of the involved forbidden nonunique <jats:inline-formula><mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"><mml:mi>β</mml:mi></mml:math></jats:inline-formula> transitions have been deployed. The fourth-forbidden nonunique decay transitions <jats:sup>113</jats:sup><jats:inline-formula><mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"><mml:mi mathvariant=\"normal\">C</mml:mi><mml:mi mathvariant=\"normal\">d</mml:mi><mml:mrow><mml:mo stretchy=\"false\">(</mml:mo><mml:mrow><mml:mn>1</mml:mn><mml:mo>/</mml:mo><mml:msubsup><mml:mrow><mml:mn>2</mml:mn></mml:mrow><mml:mrow><mml:mtext>g.s.</mml:mtext></mml:mrow><mml:mrow><mml:mo>+</mml:mo></mml:mrow></mml:msubsup></mml:mrow><mml:mo stretchy=\"false\">)</mml:mo></mml:mrow><mml:msup><mml:mrow><mml:mo>→</mml:mo><mml:mspace width=\"0.27em\"/></mml:mrow><mml:mrow><mml:mn>113</mml:mn></mml:mrow></mml:msup><mml:mi mathvariant=\"normal\">I</mml:mi><mml:mi mathvariant=\"normal\">n</mml:mi><mml:mrow><mml:mo stretchy=\"false\">(</mml:mo><mml:mrow><mml:mn>9</mml:mn><mml:mo>/</mml:mo><mml:msubsup><mml:mrow><mml:mn>2</mml:mn></mml:mrow><mml:mrow><mml:mtext>g.s.</mml:mtext></mml:mrow><mml:mrow><mml:mo>+</mml:mo></mml:mrow></mml:msubsup></mml:mrow><mml:mo stretchy=\"false\">)</mml:mo></mml:mrow></mml:math></jats:inline-formula> and <jats:sup>115</jats:sup><jats:inline-formula><mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"><mml:mi mathvariant=\"normal\">I</mml:mi><mml:mi mathvariant=\"normal\">n</mml:mi><mml:mrow><mml:mo stretchy=\"false\">(</mml:mo><mml:mrow><mml:mn>9</mml:mn><mml:mo>/</mml:mo><mml:msubsup><mml:mrow><mml:mn>2</mml:mn></mml:mrow><mml:mrow><mml:mtext>g.s.</mml:mtext></mml:mrow><mml:mrow><mml:mo>+</mml:mo></mml:mrow></mml:msubsup></mml:mrow><mml:mo stretchy=\"false\">)</mml:mo></mml:mrow><mml:msup><mml:mrow><mml:mo>→</mml:mo><mml:mspace width=\"0.27em\"/></mml:mrow><mml:mrow><mml:mn>115</mml:mn></mml:mrow></mml:msup><mml:mi mathvariant=\"normal\">S</mml:mi><mml:mi mathvariant=\"normal\">n</mml:mi><mml:mrow><mml:mo stretchy=\"false\">(</mml:mo><mml:mrow><mml:mn>1</mml:mn><mml:mo>/</mml:mo><mml:msubsup><mml:mrow><mml:mn>2</mml:mn></mml:mrow><mml:mrow><mml:mtext>g.s.</mml:mtext></mml:mrow><mml:mrow><mml:mo>+</mml:mo></mml:mrow></mml:msubsup></mml:mrow><mml:mo stretchy=\"false\">)</mml:mo></mml:mrow></mml:math></jats:inline-formula> represent theoretically and experimentally much-studied cases where the total <jats:inline-formula><mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"><mml:mi>β</mml:mi></mml:math></jats:inline-formula> spectra consist of these single transitions. In these particular cases the TAGS method could be used to assess the effective value of <jats:inline-formula><mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"><mml:msub><mml:mrow><mml:mi>g</mml:mi></mml:mrow><mml:mrow><mml:mtext>A</mml:mtext></mml:mrow></mml:msub></mml:math></jats:inline-formula>. In the present work we have identified five more interesting cases where a total <jats:inline-formula><mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"><mml:mi>β</mml:mi></mml:math></jats:inline-formula> spectrum consists of a single transition. These spectra correspond to second-forbidden nonunique transitions and are <jats:inline-formula><mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"><mml:msub><mml:mrow><mml:mi>g</mml:mi></mml:mrow><mml:mrow><mml:mtext>A</mml:mtext></mml:mrow></mml:msub></mml:math></jats:inline-formula> and/or sNME dependent, where sNME denotes the so-called small relativistic vector nuclear matrix element. These studies have been performed using the nuclear shell model with well established effective Hamiltonians. With this we target to <jats:inline-formula><mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"><mml:mi>β</mml:mi></mml:math></jats:inline-formula> transitions that would potentially be of high interest for the TAGS and present and future dedicated <jats:inline-formula><mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"><mml:mi>β</mml:mi></mml:math></jats:inline-formula>-spectrum experiments.","PeriodicalId":12507,"journal":{"name":"Frontiers in Physics","volume":null,"pages":null},"PeriodicalIF":1.9000,"publicationDate":"2024-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Spectral shapes of second-forbidden single-transition nonunique β decays assessed using the nuclear shell model\",\"authors\":\"Marlom Ramalho, Jouni Suhonen, Andrei Neacsu, Sabin Stoica\",\"doi\":\"10.3389/fphy.2024.1455778\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Experimental and theoretical studies of <jats:inline-formula><mml:math xmlns:mml=\\\"http://www.w3.org/1998/Math/MathML\\\"><mml:mi>β</mml:mi></mml:math></jats:inline-formula> electrons (electrons emitted in <jats:inline-formula><mml:math xmlns:mml=\\\"http://www.w3.org/1998/Math/MathML\\\"><mml:msup><mml:mrow><mml:mi>β</mml:mi></mml:mrow><mml:mrow><mml:mo>−</mml:mo></mml:mrow></mml:msup></mml:math></jats:inline-formula>-decay transitions) and their <jats:inline-formula><mml:math xmlns:mml=\\\"http://www.w3.org/1998/Math/MathML\\\"><mml:mi>β</mml:mi></mml:math></jats:inline-formula>-electron spectra have recently experienced a rapid expansion. These <jats:inline-formula><mml:math xmlns:mml=\\\"http://www.w3.org/1998/Math/MathML\\\"><mml:mi>β</mml:mi></mml:math></jats:inline-formula> spectral shapes have been used to study total <jats:inline-formula><mml:math xmlns:mml=\\\"http://www.w3.org/1998/Math/MathML\\\"><mml:mi>β</mml:mi></mml:math></jats:inline-formula> spectra of fission-product nuclei in the quest for explanation of the reactor-flux anomalies, and individual <jats:inline-formula><mml:math xmlns:mml=\\\"http://www.w3.org/1998/Math/MathML\\\"><mml:mi>β</mml:mi></mml:math></jats:inline-formula> transitions in search for <jats:inline-formula><mml:math xmlns:mml=\\\"http://www.w3.org/1998/Math/MathML\\\"><mml:mi>β</mml:mi></mml:math></jats:inline-formula> spectral shapes sensitive to the effective value of the weak axial coupling <jats:inline-formula><mml:math xmlns:mml=\\\"http://www.w3.org/1998/Math/MathML\\\"><mml:msub><mml:mrow><mml:mi>g</mml:mi></mml:mrow><mml:mrow><mml:mtext>A</mml:mtext></mml:mrow></mml:msub></mml:math></jats:inline-formula>. In the former case the TAGS (total absorption gamma-ray spectroscopy) can be efficiently used to measure the total <jats:inline-formula><mml:math xmlns:mml=\\\"http://www.w3.org/1998/Math/MathML\\\"><mml:mi>β</mml:mi></mml:math></jats:inline-formula> spectral shapes and in the latter case dedicated measurements of the involved forbidden nonunique <jats:inline-formula><mml:math xmlns:mml=\\\"http://www.w3.org/1998/Math/MathML\\\"><mml:mi>β</mml:mi></mml:math></jats:inline-formula> transitions have been deployed. The fourth-forbidden nonunique decay transitions <jats:sup>113</jats:sup><jats:inline-formula><mml:math xmlns:mml=\\\"http://www.w3.org/1998/Math/MathML\\\"><mml:mi mathvariant=\\\"normal\\\">C</mml:mi><mml:mi mathvariant=\\\"normal\\\">d</mml:mi><mml:mrow><mml:mo stretchy=\\\"false\\\">(</mml:mo><mml:mrow><mml:mn>1</mml:mn><mml:mo>/</mml:mo><mml:msubsup><mml:mrow><mml:mn>2</mml:mn></mml:mrow><mml:mrow><mml:mtext>g.s.</mml:mtext></mml:mrow><mml:mrow><mml:mo>+</mml:mo></mml:mrow></mml:msubsup></mml:mrow><mml:mo stretchy=\\\"false\\\">)</mml:mo></mml:mrow><mml:msup><mml:mrow><mml:mo>→</mml:mo><mml:mspace width=\\\"0.27em\\\"/></mml:mrow><mml:mrow><mml:mn>113</mml:mn></mml:mrow></mml:msup><mml:mi mathvariant=\\\"normal\\\">I</mml:mi><mml:mi mathvariant=\\\"normal\\\">n</mml:mi><mml:mrow><mml:mo stretchy=\\\"false\\\">(</mml:mo><mml:mrow><mml:mn>9</mml:mn><mml:mo>/</mml:mo><mml:msubsup><mml:mrow><mml:mn>2</mml:mn></mml:mrow><mml:mrow><mml:mtext>g.s.</mml:mtext></mml:mrow><mml:mrow><mml:mo>+</mml:mo></mml:mrow></mml:msubsup></mml:mrow><mml:mo stretchy=\\\"false\\\">)</mml:mo></mml:mrow></mml:math></jats:inline-formula> and <jats:sup>115</jats:sup><jats:inline-formula><mml:math xmlns:mml=\\\"http://www.w3.org/1998/Math/MathML\\\"><mml:mi mathvariant=\\\"normal\\\">I</mml:mi><mml:mi mathvariant=\\\"normal\\\">n</mml:mi><mml:mrow><mml:mo stretchy=\\\"false\\\">(</mml:mo><mml:mrow><mml:mn>9</mml:mn><mml:mo>/</mml:mo><mml:msubsup><mml:mrow><mml:mn>2</mml:mn></mml:mrow><mml:mrow><mml:mtext>g.s.</mml:mtext></mml:mrow><mml:mrow><mml:mo>+</mml:mo></mml:mrow></mml:msubsup></mml:mrow><mml:mo stretchy=\\\"false\\\">)</mml:mo></mml:mrow><mml:msup><mml:mrow><mml:mo>→</mml:mo><mml:mspace width=\\\"0.27em\\\"/></mml:mrow><mml:mrow><mml:mn>115</mml:mn></mml:mrow></mml:msup><mml:mi mathvariant=\\\"normal\\\">S</mml:mi><mml:mi mathvariant=\\\"normal\\\">n</mml:mi><mml:mrow><mml:mo stretchy=\\\"false\\\">(</mml:mo><mml:mrow><mml:mn>1</mml:mn><mml:mo>/</mml:mo><mml:msubsup><mml:mrow><mml:mn>2</mml:mn></mml:mrow><mml:mrow><mml:mtext>g.s.</mml:mtext></mml:mrow><mml:mrow><mml:mo>+</mml:mo></mml:mrow></mml:msubsup></mml:mrow><mml:mo stretchy=\\\"false\\\">)</mml:mo></mml:mrow></mml:math></jats:inline-formula> represent theoretically and experimentally much-studied cases where the total <jats:inline-formula><mml:math xmlns:mml=\\\"http://www.w3.org/1998/Math/MathML\\\"><mml:mi>β</mml:mi></mml:math></jats:inline-formula> spectra consist of these single transitions. In these particular cases the TAGS method could be used to assess the effective value of <jats:inline-formula><mml:math xmlns:mml=\\\"http://www.w3.org/1998/Math/MathML\\\"><mml:msub><mml:mrow><mml:mi>g</mml:mi></mml:mrow><mml:mrow><mml:mtext>A</mml:mtext></mml:mrow></mml:msub></mml:math></jats:inline-formula>. In the present work we have identified five more interesting cases where a total <jats:inline-formula><mml:math xmlns:mml=\\\"http://www.w3.org/1998/Math/MathML\\\"><mml:mi>β</mml:mi></mml:math></jats:inline-formula> spectrum consists of a single transition. These spectra correspond to second-forbidden nonunique transitions and are <jats:inline-formula><mml:math xmlns:mml=\\\"http://www.w3.org/1998/Math/MathML\\\"><mml:msub><mml:mrow><mml:mi>g</mml:mi></mml:mrow><mml:mrow><mml:mtext>A</mml:mtext></mml:mrow></mml:msub></mml:math></jats:inline-formula> and/or sNME dependent, where sNME denotes the so-called small relativistic vector nuclear matrix element. These studies have been performed using the nuclear shell model with well established effective Hamiltonians. With this we target to <jats:inline-formula><mml:math xmlns:mml=\\\"http://www.w3.org/1998/Math/MathML\\\"><mml:mi>β</mml:mi></mml:math></jats:inline-formula> transitions that would potentially be of high interest for the TAGS and present and future dedicated <jats:inline-formula><mml:math xmlns:mml=\\\"http://www.w3.org/1998/Math/MathML\\\"><mml:mi>β</mml:mi></mml:math></jats:inline-formula>-spectrum experiments.\",\"PeriodicalId\":12507,\"journal\":{\"name\":\"Frontiers in Physics\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":1.9000,\"publicationDate\":\"2024-08-15\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Frontiers in Physics\",\"FirstCategoryId\":\"101\",\"ListUrlMain\":\"https://doi.org/10.3389/fphy.2024.1455778\",\"RegionNum\":3,\"RegionCategory\":\"物理与天体物理\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"PHYSICS, MULTIDISCIPLINARY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Frontiers in Physics","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.3389/fphy.2024.1455778","RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"PHYSICS, MULTIDISCIPLINARY","Score":null,"Total":0}
Spectral shapes of second-forbidden single-transition nonunique β decays assessed using the nuclear shell model
Experimental and theoretical studies of β electrons (electrons emitted in β−-decay transitions) and their β-electron spectra have recently experienced a rapid expansion. These β spectral shapes have been used to study total β spectra of fission-product nuclei in the quest for explanation of the reactor-flux anomalies, and individual β transitions in search for β spectral shapes sensitive to the effective value of the weak axial coupling gA. In the former case the TAGS (total absorption gamma-ray spectroscopy) can be efficiently used to measure the total β spectral shapes and in the latter case dedicated measurements of the involved forbidden nonunique β transitions have been deployed. The fourth-forbidden nonunique decay transitions 113Cd(1/2g.s.+)→113In(9/2g.s.+) and 115In(9/2g.s.+)→115Sn(1/2g.s.+) represent theoretically and experimentally much-studied cases where the total β spectra consist of these single transitions. In these particular cases the TAGS method could be used to assess the effective value of gA. In the present work we have identified five more interesting cases where a total β spectrum consists of a single transition. These spectra correspond to second-forbidden nonunique transitions and are gA and/or sNME dependent, where sNME denotes the so-called small relativistic vector nuclear matrix element. These studies have been performed using the nuclear shell model with well established effective Hamiltonians. With this we target to β transitions that would potentially be of high interest for the TAGS and present and future dedicated β-spectrum experiments.
期刊介绍:
Frontiers in Physics publishes rigorously peer-reviewed research across the entire field, from experimental, to computational and theoretical physics. This multidisciplinary open-access journal is at the forefront of disseminating and communicating scientific knowledge and impactful discoveries to researchers, academics, engineers and the public worldwide.