Show simple item record

dc.contributor.authorKostensalo, Joel
dc.contributor.authorSuhonen, Jouni
dc.contributor.authorVolkmer, Juliane
dc.contributor.authorZatschler, Stefan
dc.contributor.authorZuber, Kai
dc.identifier.citationKostensalo, J., Suhonen, J., Volkmer, J., Zatschler, S., & Zuber, K. (2021). Confirmation of gA quenching using the revised spectrum-shape method for the analysis of the 113Cd β-decay as measured with the COBRA demonstrator. <i>Physics Letters B</i>, <i>822</i>, Article 136652. <a href="" target="_blank"></a>
dc.description.abstractIn this article we present an updated spectrum-shape analysis of the113Cd fourfold forbidden non-uniqueβ-decay transition in order to address the quenching of the weak axial-vector coupling gA in low-momentum exchange nuclear processes. The experimental data were collected in a dedicated low-threshold run with the COBRA demonstrator at the LNGS and resulted in 44 individual113Cdspectra. These data are evaluated in the context of three nuclear model frameworks based on a revised version of the spectrum-shape method and the conserved vector current hypothesis. The novel idea devised in the present work is to fit the value of the small relativistic nuclear matrix element (s-NME) driving the nuclear model calculations, which remained essentially as a free parameter in previous studies. This is done by tuning the nuclear structure calculations and making use of the interplay of gA and the s-NME such that the experimentally known113Cd half-life gets reproducible by the different frameworks. In this way, a best fit s-NME value can be derived for each of the considered nuclear models, which finally enters the template calculations used to perform the spectrum-shape analysis for each of the obtained113Cd spectra. The primary analysis strategy results in significantly quenched values of the axial-vector coupling for all three nuclear models: gA(ISM)=0.907±0.064,gA(MQPM)=0.993±0.063andgA(IBFM-2)=0.828±0.140. Moreover, with our data-driven approach one of the main shortcomings of the spectrum-shape method has been resolved. This achievement is a milestone in the description of strongly forbiddenβ-decays and adds to the indications for the existence of a quenching of gA in low-momentum exchange nuclear processes.en
dc.relation.ispartofseriesPhysics Letters B
dc.rightsCC BY 4.0
dc.subject.other113Cd β-decay
dc.subject.otheraxial-vector coupling
dc.subject.othergA quenching
dc.subject.otherspectrum-shape method
dc.titleConfirmation of gA quenching using the revised spectrum-shape method for the analysis of the 113Cd β-decay as measured with the COBRA demonstrator
dc.contributor.laitosFysiikan laitosfi
dc.contributor.laitosDepartment of Physicsen
dc.rights.copyright© 2021 The Authors. Published by Elsevier B.V.
dc.relation.funderSuomen Akatemiafi
dc.relation.funderAcademy of Finlanden
jyx.fundingprogramAkatemiahanke, SAfi
jyx.fundingprogramAcademy Project, AoFen
jyx.fundinginformationthe collaboration would like tothank the German Research Foundation (Deutsche Forschungs-gemeinschaft, DFG) for its past funding and the support of theCOBRA XDEM upgrade under the project numbers ZU123/3and GO1133/1. Additionally, the support by the Academy of Finland under the project number 318043 and from the Jennyand Antti Wihuri Foundation is acknowledged.

Files in this item


This item appears in the following Collection(s)

Show simple item record

CC BY 4.0
Except where otherwise noted, this item's license is described as CC BY 4.0