The Highs And Lows Of The A=100 Region: Vibration-To-Rotation Evolution In Mo And Ru Isotopes

摘要

Nuclei below the Z = 50 magic shell gap with A～100 show a wide variety of structural phenomena. These include excellent examples of vibrational collectivity at low-spins, which give way to more rotational-like excitations with increasing angular momentum. In this paper we present recent results from an experiment performed at Yale to study the yrast evolution of states in ~(98,99)Mo and ~(101,102)Ru. Although the high-spin data is consistent with predictions from rotational model theories, we propose a simple presciption to distinguish between vibrational and rotational regimes of angular momentum generation. When applied to the nuclei of interest, a clear picture emerges of how these two mechanisms of collective spin generation compete in this region.