Identification of low-energy isovector octupole states in 144Nd

[摘要] Recently, first candidates for low-lying isovector states in the octupole sector were suggested. The unambiguous identification of those states will contribute to the decomposition of the octupole-octupole residual interaction in an isoscalar and isovector part. This will help us understand the octupole degree of freedom. In144Nd the 3-state at 2778 keV is a good candidate for such a "mixed-symmetry'' octupole state. In order to clarify the nature of this state, a143Nd(n, γ)-experiment was conducted with the EXILL-setup. Following neutron capture the 3-states are populated and EXILL provides the opportunity to determine the multipole-mixing ratios of the 3i-→31-transitions. For the transition from the "mixed-symmetry" octupole state to the symmetric 31-state we expect a strong M1 component.

[发布机构] Institut. für Kernpliysik, TU Darmstadt, Sclilossgartenstr. 9, Darmstadt; 64289, Germany^1;School of Eng. and Comp., Uuiv. of the West of Scotland, High Street, Paisley; PA1 2BE, United Kingdom^2;Scottish Universities Physics Alliance, University Avenue, Glasgow; G12 8QQ, United Kingdom^3;Wright Laboratory, Yale Univ, P.O. Box 208120, New Haven; CT; 06520-8120, United States^4;Institut Laue-Langevin, 71 avenue des Martyrs, Grenoble; 38000, France^5;Grand Accèlèrateur National DTons Lourds, Boulevard Henri Becquerel, Caen; 14000, France^6;Institut für Kernpliysik, Universität zu Köhl, Zülpicher Str. 77, Köln; 50937, Germany^7;LPSC, UJF Grenoble i, 53 avenue des Martyrs, Grenoble Cedex; 38026, France^8;Faculty of Physics, University of Warsaw, ul. Pasteura 5, Warsaw; 02-093, Poland; (10) Dep. of Physics, U.S. Naval Academy, 121 Blake Road, Annapolis; MD; 21402, United States^9

[关键词] Degree of freedom;Low-energy;Mixing ratios;Multipoles;Neutron capture;Residual interactions