Measuring the difference in nuclear charge radius of Xe isotopes by EUV spectroscopy of highly charged Na-like ions

Abstract

The difference in the mean-square nuclear charge radius of xenon isotopes was measured utilizing a method based on extreme ultraviolet spectroscopy of highly charged Na-like ions. The isotope shift of the Na-like <i>D</i>1 (3<i>s</i> ² <i>S</i> _1<i>/</i>2 - 3<i>p</i> ² <i>P</i> _1/2) transition between the ¹²⁴Xe and ¹³⁶Xe isotopes was experimentally determined using the electron-beam ion-trap facility at the National Institute of Standards and Technology. The mass-shift and the field-shift coefficients were calculated with enhanced precision by the relativistic many-body perturbation theory and multiconfiguration Dirac-Hartree-Fock method. The mean-square nuclear charge radius difference was found to be <i>δ</i>〈<i>r</i> ²〉^136,124 = 0.269(42) fm². Our result has smaller uncertainty than previous experimental results and agrees with the literature values.