Decay properties of 68,69,70Mn: Probing collectivity up to N = 44 in Fe isotopic chain

G Benzoni,A Gottardo,R Taniuchi,V Modamio-Hoybjor,L Coraggio,I Kuti,B Melon,G De Angelis,O Wieland,J Wu,H Watanabe,H Watanabe,J Taprogge,F Camera,A Bracco,L Sinclair,L Sinclair,P Doornenbal,D Mengoni,M.-C Delattre,R Orlandi,N Blasi,N Blasi,P.-A Söderström,D Sohler,R Daido,R Avigo,A Gargano,S Momiyama,Zsolt Dombrádi ,M Nııkura ,Takamichi Miyazaki ,T Isobe,F Browne,F Browne,Z Patel,Z Patel,N Itaco,N Itaco,S Rice,S Rice,Zsolt Vajta ,K Matsui,G Lorusso,T Sumikama,E Šahin ,Ana Isabel Morales ,Ana Isabel Morales ,H Sakuraï ,F L Bello Garrote ,Y Fang,J.j Valiente-Dobón ,R Yokoyama,S Ceruti,Z Y Xu ,Z Y Xu ,D R Napoli ,S Nishimura,F C L Crespi ,H Baba,M Yalçınkaya

doi:10.1016/j.physletb.2015.10.025

Abstract

The β decays Mn68→Fe68, Mn69→Fe69 and Mn70→Fe70 have been measured at the RIBF facility at RIKEN using the EURICA γ spectrometer combined with an active stopper consisting of a stack of Si detectors. The nuclei were produced as fission fragments from a beam of 238U at a bombarding energy of 345 MeV/nucleon impinging on a Be target and selected using the BigRIPS separator. Half-lives and β-delayed neutron emission probabilities have been extracted for these decays, together with first experimental information on excited states populated in 69,70Fe. The data indicate a continuously increasing deformation for Fe isotopes up to A=70. This is interpreted, as for Cr isotopes, in terms of the interplay between the quadrupole correlations of the ν1d5/2 and ν0g9/2 orbitals and the monopole component of the π0f7/2–ν0f5/2 interaction.

Highlights

The β decays 68Mn → 68Fe, 69Mn → 69Fe and 70Mn → 70Fe have been measured at the Radioactive-Isotope Beam Factory (RIBF) facility at RIKEN using the EURICA γ spectrometer combined with an active stopper consisting of a stack of Si detectors
Halflives and β-delayed neutron emission probabilities have been extracted for these decays, together with first experimental information on excited states populated in 69,70Fe
The study of the evolution of excited states for the Cr, Fe, Zn, Ge isotopes provides a stringent test to shell model calculations leading to N = 50

Summary

Introduction

The β decays 68Mn → 68Fe, 69Mn → 69Fe and 70Mn → 70Fe have been measured at the RIBF facility at RIKEN using the EURICA γ spectrometer combined with an active stopper consisting of a stack of Si detectors. Halflives and β-delayed neutron emission probabilities have been extracted for these decays, together with first experimental information on excited states populated in 69,70Fe. The data indicate a continuously increasing deformation for Fe isotopes up to A = 70.

Results

Conclusion