Electric quadrupole moments and isotope shifts of radioactive sodium isotopes

Abstract

On-line high resolution laser spectroscopy has been performed on radioactive $^{20\ensuremath{-}31}\mathrm{Na}$. New values for the isotope shift of the ${D}_{1}$ line of $^{20\ensuremath{-}24,31}\mathrm{Na}$ relative to $^{23}\mathrm{Na}$ have been obtained. The spectroscopic quadrupole moments of $^{21,25\ensuremath{-}29}\mathrm{Na}$ have been determined using a double resonance method. The ${D}_{2}$ line hyperfine structure of $^{21,25\ensuremath{-}27}\mathrm{Na}$ has also been studied by laser optical spectroscopy. Results are in agreement with those obtained by rf double resonance. No evidence of the sudden onset of a deformation expected at $N=20$ has been found. A strong shell effect in the change in the mean-square charge radius is exhibited at $N=14$.NUCLEAR REACTIONS $^{20\ensuremath{-}24,31}\mathrm{Na}$; measured isotope shift. $^{20\ensuremath{-}22,24,31}\mathrm{Na}$; measured hyperfine constants $A(3s ^{2}S_{\frac{1}{2}})$, $A(3p ^{2}P_{\frac{1}{2}})$; deduced $\ensuremath{\mu}$. $^{21,25\ensuremath{-}29}\mathrm{Na}$; measured hyperfine constants $A(3p ^{2}P_{\frac{3}{2}})$, $B(3p ^{2}P_{\frac{3}{2}})$; deduced $Q$. Atomic beam laser spectroscopy and laser rf double-resonance spectroscopy.