Half-lives of ground and isomeric states in 97Cd and the astrophysical origin of 96Ru

G Lorusso ,J Pereira,D Bazin,T N Ginter ,Richard H Cyburt ,B A Brown ,A Becerril ,A Estradé ,C J Guess ,F Montes ,G Perdikakis ,H Schatz ,J Stoker ,M Matoš ,M Portillo ,R Meharchand ,A Gade ,H L Crawford ,K Minamisono ,K Smith ,M Hausmann ,T Baumann ,A Stolz ,J S Berryman ,A M Amthor ,P F Mantica ,G W Hitt ,R G T Zegers

doi:10.1016/j.physletb.2011.03.043

Abstract

First experimental evidence for a high-spin isomer (25/2+) in 97Cd, a waiting point in the astrophysical rapid proton capture process, is presented. The data were obtained in β-decay studies at NSCL using the new RF Fragment Separator system and detecting β-delayed protons and β-delayed γ rays. Decays from ground and isomeric states were disentangled, and proton emission branches were determined for the first time. We find half-lives of 1.10(8) s and 3.8(2) s, and β-delayed proton emission branches of 12(2)% and 25(4)% were deduced for the ground and isomeric states, respectively. With these results, the nuclear data needed to determine an rp-process contribution to the unknown origin of solar 96Ru are in place. When the new data are included in astrophysical rp-process calculations, one finds that an rp-process origin of 96Ru is unlikely.

Highlights

First experimental evidence for a high-spin isomer (25/2+) in 97Cd, a waiting point in the astrophysical rapid proton capture process, is presented
The data were obtained in β-decay studies at NSCL using the new RF Fragment Separator system and detecting β-delayed protons and β-delayed γ rays
Decays from ground and isomeric states were disentangled, and proton emission branches were determined for the first time

Summary

Introduction

First experimental evidence for a high-spin isomer (25/2+) in 97Cd, a waiting point in the astrophysical rapid proton capture process, is presented. Decays from ground and isomeric states were disentangled, and proton emission branches were determined for the first time. We find half-lives of 1.10(8) s and 3.8(2) s, and β-delayed proton emission branches of 12(2)% and 25(4)% were deduced for the ground and isomeric states, respectively.

Results

Conclusion