HYPERFINE STRUCTURE OF 6S6P 1P1 LEVEL OF STABLE YTTERBIUM ISOTOPES

The techniques of level-crossing and anticrossing spectroscopy have been applied in a study of the hfs of the excited 6s6p P11 level of the stable ytterbium isotopes. Details concerning the anticrossing signal, its nature, shape, intensity, and dependence on polarized light are given. The values we infer for the hfs constants are A(P11)gJ=206.0(16) Mc/sec for Yb171 (I=12) and A(P11)gJ=56.9(5) Mc/sec, B(P11)gJ=575(7) Mc/sec for Yb173 (I=52). The measured values for the P11 level are compared with those calculated from the known hfs constants of the P13 and P23 levels. Fair agreement is obtained with predictions based on the modified Breit-Wills theory given by Lurio. © 1969 The American Physical Society.