Analysis of excited states in 13C and their cluster structure

Ivano Lombardo

doi:10.1051/epjconf/201922301034

Abstract

An accurate understanding of the spectroscopy of 13C is key to understand clustering phenomena in light nuclear systems. In this nucleus, many theoretical models predict the existence of α-cluster configurations, stabilized by the presence of an extra neutron. Despite of its importance, the spectroscopy of13C is still affected by ambiguities, demanding for new data against which benchmarking the models. We improve the knowledge on the 13C level scheme by means of a comprehensive R-matrix analysis of several experimental data sets. Our new spectroscopic information contributes to solve existing ambiguities in 13C structure and will serve a valid benchmark for theoretical models attempting to describe clustering in neutron rich systems.

Highlights

Carbon isotopes represent a unique opportunity to investigate clustering phenomena in light nuclear systems as a function of the neutron excess
The overall agreement of the R-matrix calculation and the data is excellent at all energies, as clearly visible in figure
The resulting parameters are summarized in Ref. [22] and improve the overall spectroscopy of 13C in this energy region

Summary

Introduction

Carbon isotopes represent a unique opportunity to investigate clustering phenomena in light nuclear systems as a function of the neutron excess. High-precision experiments pointed out instead the occurrence of D3h triangular symmetry in such nucleus [2, 3], triggering a renovated interest for three-centers cluster structures in nuclei In this framework, it is fundamental to fully understand the spectroscopy of the carbon isotopes that are obtained by removing or adding a neutron to the self-conjugate 12C, namely 11C and 13C. The first has been the subject of recent investigations [4,5,6] that pointed out excited states associated to cluster-like structures and discussed their relevance in astrophysics [7] For the latter, the neutron rich 13C, the situation is much more complicated. More details on this analysis and related interpretations can be found in Ref. [22]

Construction of data sets

R-matrix analysis of data

Conclusions and perspectives