Katharina E. Ide
(Technische Universität Darmstadt, Dept. of Physics, Institute for Nuclear Physics)
The nucleus $^{152}$Sm is well known to be located at the $N=90$ quantum shape-phase transition (QSPT) boundary. Since the scissors mode (SM) is a collective, isovector excitation, its decay characteristics depend on the proton-neutron residual interactions and are sensitive to the QSPT. The SM is known for its large $M1$-excitation strength, however, data on isovector $E2$ properties are sparse [1]. The SM of $^{152}$Sm was investigated in a nuclear resonance fluorescence experiment performed at the High-Intensity $\gamma$-Ray Source with a quasi-monoenergetic, polarized photon beam with an energy of 2.99(5) MeV. Emitted photons were detected by four high-purity germanium detectors positioned at angles sensitive to the multipolarities of the decay radiation of $1^\pi$ states. The isovector $E2$ transition of the SM of $^{152}$Sm to the first 2$^+$ state has been deduced from the $E2/M1$ multipole mixing ratio of the $1^+_\text{sc} \to 2^+_1$ transition and its previously known transition rate. Experimental results are compared to predictions of the interacting boson model 2, yielding local values for proton and neutron effective quadrupole boson charges [2].
*Supported by the DFG under grant No. SFB 1245
[1] T.Beck et al., Phys. Rev. Lett. 118 (2017) 212502
[2] K. E. Ide et al., Phys. Rev. C 103 (2021) 054302
Katharina E. Ide
(Technische Universität Darmstadt, Dept. of Physics, Institute for Nuclear Physics)
T. Beck
(Technische Universität Darmstadt, Dept. of Physics, Institute for Nuclear Physics)
M. Berger
(Technische Universität Darmstadt, Dept. of Physics, Institute for Nuclear Physics)
S. Finch
(Department of Physics, Duke University and Triangle Universities Nuclear Laboratory)
U. Friman-Gayer
(Technische Universität Darmstadt, Dept. of Physics, Institute for Nuclear Physics)
J. Kleemann
(Technische Universität Darmstadt, Dept. of Physics, Institute for Nuclear Physics)
Krishichayan
(Department of Physics, Duke University and Triangle Universities Nuclear Laboratory)
B. Löher
(Technische Universität Darmstadt, Dept. of Physics, Institute for Nuclear Physics)
O. Papst
(Technische Universität Darmstadt, Dept. of Physics, Institute for Nuclear Physics)
N. Pietralla
(Technische Universität Darmstadt, Dept. of Physics, Institute for Nuclear Physics)
D. Savran
(ExtreMe Matter Institute EMMI and Research Division, GSI Helmholtzzentrum für Schwerionenforschung)
W. Tornow
(Department Department of Physics, Duke University and Triangle Universities Nuclear Laboratory)
M. Weinert
(Institut für Kernphysik, Universität zu Köln)
V. Werner
(Technische Universität Darmstadt, Dept. of Physics, Institute for Nuclear Physics)
J. Wiederhold
(Technische Universität Darmstadt, Dept. of Physics, Institute for Nuclear Physics)
A. Zilges
(Institut für Kernphysik, Universität zu Köln)
