학술논문
Structure of high-lying levels populated in the $^{96}$Y $\rightarrow ^{96}$Zr $\beta$ decay
Document Type
Working Paper
Author
Mashtakov, K. R.; Ponomarev, V. Yu.; 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.
Source
Subject
Language
Abstract
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.