In-source laser spectroscopy of dysprosium isotopes at the ISOLDE-RILIS

K Chrysalidis,A.E Barzakh,R Ahmed,A.N Andreyev,J Ballof,J.G Cubiss,D.V Fedorov,V.N Fedosseev,L.M Fraile,R.D Harding,U Köster,B.A Marsh,C Raison,J.P Ramos,R.E Rossel,S Rothe,K Wendt,S.G Wilkins

doi:10.1016/j.nimb.2019.04.021

Abstract

A number of radiogenically produced dysprosium isotopes have been studied by in-source laser spectroscopy at ISOLDE using the Resonance Ionization Laser Ion Source (RILIS). Isotope shifts were measured relative to 152Dy in the 4f106s25I8 (gs) →4f106s6p(8,1)8o (418.8nmvac) resonance transition. The electronic factor, F, and mass shift factor, M, were extracted and used for determining the changes in mean-squared charge radii for 145mDy and 147mDy for the first time.

Highlights

The Resonance Ionization Laser Ion Source (RILIS) is the most selective of all ion sources available at the ISOLDE radioactive beam facility [1]
The spectral resolution of in-source measurements is limited by Doppler-broadening of the spectral lines inside the ion source
There have been several experimental campaigns, in which this in-source spectroscopy has been successfully applied (e.g. [2]) or where isomer separation was provided for higher selectivity during nuclear spectroscopy experiments (e.g. [3])

Summary

Introduction

The Resonance Ionization Laser Ion Source (RILIS) is the most selective of all ion sources available at the ISOLDE radioactive beam facility [1]. The isotope production takes place inside a thick target, on which protons, provided by CERN’s Proton Synchrotron Booster (PSB), impinge with an energy of 1.4 GeV. The resulting ions are extracted, accelerated up to 60 keV and mass separated by a dipole magnet according to their mass-to-charge ratio. During so-called ‘in-source laser spectroscopy’, the RILIS lasers are used a to probe a specific spectroscopic transition of the ionization scheme of different isotopes of one element. [2]) or where isomer separation was provided for higher selectivity during nuclear spectroscopy experiments We report on the first in-source spectroscopy study of dysprosium radioisotopes, demonstrating the suitability of this method for a future extended study of IS in the dysprosium isotopic chain

Experimental setup

Results

Outlook