New f-values in neutral lead obtained by time-resolved laser spectroscopy,and astrophysical applications

Natural radiative lifetimes have been measured for three odd-parity levels of neutral lead using time-resolved UV laser-induced fluorescence from a la ser-produced plasma. These new lifetimes, as well as additional recent valu es obtained by laser spectroscopy, combined with theoretical branching rati os deduced from a relativistic Hartree-Fock calculation taking core polariz ation effects into account, have allowed the deduction of a new set of accu rate f-values of astrophysical interest. Using the new lifetime value for 6 p7s (1/2, 1/2)(0)degrees, a refined value of the lead abundance in the sola r photosphere is deduced: A(Pb) = 2.00 +/- 0.06 on the usual logarithmic sc ale, allowing the resolution of the long-standing discrepancy previously ob served between the solar photosphere and meteorites.