New Results on Excited States in the one-particle one-hole nucleus 56Co measured with MINIBALL detectors

A Montaner-Pizá,C Bender,E.C Simpson,V Guadilla,S Reichert,B Rubio,E Ganioglu,S.E.A Orrigo,A Algora,J Agramunt,S Hellgartner,D Mücher,W Gelletly,Y Fujita,G De Angelis,L Corradi

doi:10.1051/epjconf/201922301042

Abstract

The non-yrast states of the odd-odd nucleus 56Co have been investigated by studying the γ-rays induced in the predominantly fusion-evaporation reaction 56Fe(p,n γ)56Co at an incident energy of 10 MeV. The γ-rays were measured in-beam with four high-resolution MINIBALL-triple germanium (Ge) detectors. The experiment provided excellent data in γ-γ coincidences. The complex level scheme of 56Co was constructed mainly based on the analysis of these γ-γ coincidences. The angular distributions of the γ-rays were also analysed and allowed us to assign spin-parity values to most of the excited states in this nucleus. Despite the extensive work previously done studying the 56Co nucleus, the analysis presented in this work has resulted in a large improvement in the knowledge of its structure.

Highlights

In the present work we have studied the γ-ray de-excitation of the non-yrast states in the odd-odd nucleus 56Co (Z=27, N=29) populated in the mainly fusion-evaporation reaction 56Fe(p,nγ)56Co at an 10-MeV incident proton beam
The study of 56Co in this work was initially motivated by the observation of two 0+ states in its mirror nucleus 56Cu (Z=29, N=27) in a β+ decay experiment of 56Zn carried out at GANIL (Caen, France) [1]
These two states are populated through Fermi-type decay and correspond to the splitting of the isobaric analogue state (IAS)

Summary

Introduction

In the present work we have studied the γ-ray de-excitation of the non-yrast states in the odd-odd nucleus 56Co (Z=27, N=29) populated in the mainly fusion-evaporation reaction 56Fe(p,nγ)56Co at an 10-MeV incident proton beam. The study of 56Co in this work was initially motivated by the observation of two 0+ states in its mirror nucleus 56Cu (Z=29, N=27) in a β+ decay experiment of 56Zn carried out at GANIL (Caen, France) [1]. These two states are populated through Fermi-type decay and correspond to the splitting of the isobaric analogue state (IAS). The clusters were positioned at slightly di↵erent distances from the chamber, in order to maximise the solid-angle coverage

The level scheme of Co

Theoretical interpretation