Structure of high-lying levels populated in the \(^{96}\)Y \(\rightarrow ^{96}\)Zr \(\beta\) decay

• Published in: arXiv.org 2020-03
• Main Authors: Mashtakov, K R, V Yu Ponomarev, Scheck, M, Finch, S W, Isaak, J, Zweidinger, M, Agar, O, Bathia, C, Beck, T, Beller, J, Bowry, M, Chapman, R, Chisthi, M M R, Friman-Gayer, U, Gaffney, L P, Garrett, P E, Gregor, E T, Keatings, J M, Köster, U, Löher, B, McLean, A D, O'Donnell, D, Pai, H, Pietralla, N, Rainovski, G, Ramdhane, M, Romig, C, Rusev, G, Savran, D, Simpson, G S, Sinclair, J, Sonnabend, K, Spagnoletti, P, Tonchev, A P, Tornow, W
• Format: Article
• Language: English
• Subjects: Beta decay; Beta rays; Gamma rays; Inelastic scattering; Nuclear structure; Wave functions; Zirconium
• ISSN: 2331-8422

The nature of \(J^{\pi}=1^-\) levels of \(^{96}\)Zr below the \(\beta\)-decay \(Q_{\beta}\) value of \(^{96}\)Y has been investigated in high-resolution \(\gamma\)-ray spectroscopy following the \(\beta\) decay as well as in a campaign of inelastic photon scattering experiments. Branching ratios extracted from \(\beta\) decay allow the absolute \(E1\) excitation strength to be determined for levels populated in both reactions. The combined data represents a comprehensive approach to the wavefunction of \(1^-\) levels below the \(Q_{\beta}\) value, which are investigated in the theoretical approach of the Quasiparticle Phonon Model. This study clarifies the nuclear structure properties associated with the enhanced population of high-lying levels in the \(^{96}\)Y\(_{gs}\) \(\beta\) decay, one of the three most important contributors to the high-energy reactor antineutrino spectrum.