STARK AND ZEEMAN SPECTROSCOPIES OF 4F(6)6S6P (7)G(1-6) LEVELS IN SM-IUNDER EXTERNAL ELECTRIC AND MAGNETIC-FIELDS

Systematic study of hyperfine structures, Zeeman and Stark effects in Sm I is performed for the lowest (7)G(1-6) levels belonging to the con figuration 4f(6)6s6p by atomic-beam laser spectroscopy with fluorescen ce detection. The hyperfine coupling constants of (7)G(2-6) levels are determined. From the Zeeman splittings for the 4f(6)6s(27)F(2-6) - 4f (6)6s6p(7)G(2-6) transitions, g-values are determined for the (7)G(2-6 ) levels and the precision is improved by several orders of magnitude. From the Stark splittings for the F-7(0-3) -(7)G(1-3) transitions, te nsor polarizabilities alpha(2)(J) are determined for the upper (7)G(1- 3) levels. Particularly for the (7)G(1) level (15 650.55 cm(-1)) which has close-lying opposite-parity level, the isotope dependence of alph a(2)(J) is clearly observed for the first time.