Electric and magnetic hyperfinestructure investigations in the 5s 25p 3 and 5s 25p 26s Configurations of121, 123Sb

Abstract

Optical hyperfinestructure investigations in several spectral lines were carried out in the Sb-I spectrum from which for the first time accurate values of the hfs-splitting constantsA andB of the ground configuration 5p3 and also for five of the eight levels of the first excited configuration 5p26s were obtained. With these parameters the influence of core polarization effects is calculated to beac= −6.6(4) mK, (equivalent to a magnetic field of −283(20) kG perp-electron spin). The quadrupole momentQ121= −0.36(4) b (including Sternheimer correction) was obtained with the experimental valuesb3/2= −14.3(1.0) mK and 〈r−3〉 =11.2(3) a.u. andQ123= −0.49(5) b withb3/2= −19.9(1.0) mK resp. This evaluation also yields the relativistic correction factor η= −(C″/C′) · Sr/R′r=1.13(2). —For the first time, too, isotope shift investigations in Sb-I lines were possible which permit to determine the isotope shift constant βCexp= 40(10) mK, and a value δ〈r2〉121, 123=0.12(4) fm2 for the change in the mean square nuclear charge radius between121Sb and123Sb which is about 50 percent of the prediction of the unified nuclear model.