原子線レーザー分光法によるYbIの同位体シフトと超微細構造

Isotope shifts of 9 transitions from the ground and metastable states in Yb I were measured for 7 stable isotopes with A=168-176 by means of atomic-beam laser spectroscopy. The electric discharge was used to obtain the intense population of the metastable state in Yb I. Hyperfine constants A and B of 12 levels for 171Yb and 173Yb were determined. Reliable values of nuclear parameters λ were obtained and changes in mean square nuclear charge radii δ<r2> were deduced using both the two-parameter model and the numerical analysis. Deformations for Yb stable isotopes and the odd-even staggering effect for odd-N isotopes were discussed. Hyperfine constants A and B were analyzed with the effective operator procedure and the single-electron hyperfine parameters of 6s and 6d electrons were derived for the Yb I 4f146s6d configuration. For the 3DJ and 1D2 states of 4f146s6d, J and term dependences of isotope shifts were obtained and the parameters of the crossed-second-order effect were derived to be z6d/λ = 18(6) MHz/fm2 and g2(6s, 6d)/λ = -1120(60) MHz/fm2.Contents Abstract / p1 1.Introduction / p2 2.Experimental / p6 2.1 Experimental setup / p6 2.2 Population of the metastable state of Yb I by an electric discharge / p8 3.Theoretical Description / p14 3.1 Isotope shift / p14 3.2 Derivation of changes in mean square nuclear charge radii δ<γ²>and deformation parameters δ<β²> / p16 3.3 Hyperfine interaction / p18 3.4 Crossed-second-order (CSO) effect / p20 4.Experimental Results / p23 5.Analysis and Discussion / p31 5.1 Nuclear parameter λ / p31 5.2 δ<γ²>and δ<β²> / p35 5.3 Single-electron HF parameters for the 4f¹⁴6s6d configuration / p41 5.4 J and term dependences of IS and CSO effects for the ³DJ and ¹D₂ states of 4f¹⁴6s6d / p43 6.Conclusion / p47 Acknowledgment / p49 References / p50広島大学(Hiroshima University)博士(理学)Physical Sciencedoctora