Nuclear Structure of the Zirconium Region

Results important for the general understanding of nuclear structure have emerged from the study of the nuclei in the mass region around the neutron-deficient and neutron-rich Zirconium isotopes. This research report gives the proceedings of a workshop which brought together about 70 experts in the area. Review papers deal with the theoretical interpretation of the unusual properties of these medium-mass nuclei, using the mean field approach, a microscopic description, the interacting boson model and particle rotor calculations. Papers also discuss experimental procedures for studying nuclei far from stability and the possibility of complete spectroscopy. The reviews are supplemented by short contributions presenting very new results. Phenomena discussed include the interplay between subshell effects and the strong proton-neutron interaction in determining nuclear shape, the coexistence of different nuclear shape and the occurrence of fast beta decay.

Contenu

I Introduction.- Nuclear Structure in the Zr Region: Some Introductory Remarks.- II Shape Transitions and Shape Coexistence.- Some Results from Potential Energy Surface Calculations for Nuclei in the Mass 70-80 Region.- Collectivity of Neutron Deficient Odd Strontium and Yttrium Isotopes.- Microscopic Description of Even Ge and Se Nuclei.- Coexistence of Shapes and Structure of Nuclei in the A = 80 Region.- Competition of Oblate and Prolate Deformation in 3469,70,71,72Se.- Moments and Radii of 78-100Sr.- Experimental Evidence for Shape Coexistence in 97Sr59 and Implications for the Structure of the Odd-Odd Isotone 98Y.- Shape Coexistence and Mixing of Spherical and Deformed Shapes in the N = 60 Isotones.- Transition Probabilities and Static Moments in Transitional Nuclei.- Evidence for Shape Coexistence in Neutron-Rich Rh and Ag Nuclei.- Shape Coexistence and the Structure of Even-Even Se, Pd, and Ru Nuclei.- Monopole Degrees of Freedom in the Odd-Mass Neighbours of Even-Even Nuclei with Low-Lying 0+ Levels.- III High Spin Effects.- Techniques for the Study of the A?80 and A?100 Nuclei Far from Stability.- M1 and E2 Transition Probabilities in Kr Nuclei.- Lifetimes and Sidefeeding Times in A = 70-83 Nuclei.- The Moment of Inertia of 78Sr.- g-Factors Near the First Backbend in 82Sr and 84Sr.- Core-Related Effects on Electromagnetic Transition Strengths in Medium-Mass Nuclei.- Microscopic Description of the Ground-State and High-Spin Properties of the Light Strontiums.- IV Complete Spectroscopy.- Complete Spectroscopy.- 73Se Investigated by the (?,n?) Reaction.- Complete Spectroscopy of 87,88,89Sr with (n,?) and (d,p) Reactions?.- Quantum Chaos and the Boson-Fermion Approach to A?100 Region.- V Shell Effects.- The Approach to 2:1 Deformations Induced by Particle Numbers Around 40 and 60.- IBMF and IBFFM Approach to Nuclei in the A?100 Region.- Single-Particle Excitations and Collective Vibrational Modes in 96Zr.- Doppler-Shift Lifetime Measurements in 96Zr.- In-Beam Studies of 96Zr and 98Zr: Collective Excitations.- Band Structures in 96Zr and 98Zr Studied Through the High-Spin Beta Decays of the Y Parents.- Possible Evidence for Subshell Closures at N = 38, 40 and 56.- Subshell Closure at N = 56 in Very Neutron-Rich Bromine Isotopes.- Recent Results of Beta-Decay-Energies of Very Neutron-Rich Nuclei Around Mass Number A=100.- Level Structure of 3989Y, N = 50 Isotone.- Nuclear Structure Close to 100Sn:Excitations of the Shell Model Core.- VI Deformations.- A?80 and A?100 Nuclei Studied Within the Mean Field Approach.- On the Solution to the Large Amplitude Collective Motion of Finite Interacting Fermi Systems.- Nuclear Structure Effects along the N = Z Line.- Core Polarization Effects in Odd A?80 Nuclei.- Deformation of Light Br Isotopes: New Ground State Spin and Moment Measurements.- Anomalous Behaviour of Transition Probabilities in 75Kr.- Backbending Behaviour in the Odd Neutron Nuclei 75Kr and 79Sr.- Proton-Neutron Interaction and the 1 g Orbital in the 33?Z?50 Region.- Particle-Rotor Calculations in the A = 100 Region.- Large Inertial Moments, Pairing Reduction and the Effects of Coriolis Mixing on Rotational Bands in Odd-Z Deformed A?100 Nuclei.- The Nuclear Structure of 101,103Nb.- VII Proton-Neutron Interactions and Pairing Reductions.- Influence of the Proton-Neutron Interaction in the A?100 Region.- The Proton-Neutron Interaction in Neutron-Rich A?100 Nuclei.- The P-Factor and Atomic Mass Systematics: Application to Medium Mass Nuclei.- The Spin Dipole Interaction in Odd-Odd Nuclides.- VIII Beta Decay at A?.- Fast First-Forbidden Transitions and Subshell Closures in the Region of 96Zr.- Structure of 1+ States in Neutron Deficient Odd-Odd Indium Isotopes.- Gamow-Teller Beta Decay of Even Nuclides Near 100Sn.- Gamow-Teller Beta Decay of Neutron Rich Tc, Ru, Rh and Pd Isotopes.- Giant Gamow-Teller Excitations in 104Cd.- Index of Contributors.