Eur. Phys. J. A 13, 99-103 (2002)

Proton-neutron structure of collective excitations in

P. von Brentano¹, C. Fransen¹, A. Gade¹, A. Lisetskiy¹ and N. Pietralla<sup>1, 2

1</sup>  Institut für Kernphysik, Universität zu Köln, 50937 Köln, Germany
²  A.W. Wright Nuclear Structure Laboratory, Yale University, New Haven, CT 06520, USA

(Received: 1 May 2001)

Abstract
Resulting wave functions of low-lying states from a recent shell model calculation for the near-spherical nucleus ⁹⁴Mo are analyzed with respect to their collectivity and the proton-neutron degree of freedom. The analysis uses the Q-phonon scheme applied to the shell model and it supports the mixed-symmetry interpretation of the interacting boson model for the multiphonon structure observed recently in ⁹⁴Mo by means of -ray spectroscopy. Simple operators are obtained which generate major parts of the symmetric- and mixed-symmetry 2⁺ states in ⁹⁴Mo when applied to the calculated ground state.

PACS
21.60.Cs - Shell model.
21.10.Re - Collective levels.
23.20.Js - Multipole matrix elements.
27.60.+j - .

© Società Italiana di Fisica, Springer-Verlag 2002