HYPERFINE-STRUCTURE OF THE 6P1/2-6P3/2 MAGNETIC DIPOLE RESONANCE TRANSITION IN ELECTRODYNAMICALLY CONFINED PB-207(+)

The hyperfine splitting of the 6P1/2-6P1/2 fine structure transition in Pb-207+ ions at 710 nm has been measured by c.w. laser excitation and subsequent observation of the weak fluorescence radiation at the same wavelength. The ions were confined in an rf quadrupole trap and buffer gas cooled by collisions with He atoms at 10(-5) mbar pressure. From the observed level splitting and the simultaneously recorded transmission of a Fabry-Perot etalon we determined the hyperfine splitting constants A(6P1/2) = 13.001 (48) GHz and A(6P3/2) = 0.589(23) GHz. From a small impurity of Pb-208 of our isotopically enriched sample we determined the isotope shift of the transitions to DELTA-nu(207-208) = 252(40)MHz.