ABUNDANCES OF HEAVY ELEMENTS IN SUN

Solar abundances have been derived for Pb, Bi, Th and U. For the three first elements, the abundances are determined from the profiles of their lines obtained with the high resolution solar spectrometer installed at the Jungfraujoch Scientific Station (Switzerland) and from new oscillator strengths based on life-time measurements (Pb and Bi). The possible presence of U in the solar spectrum is also examined. Our results are (in the log NH = 12.00 scale): log NPb = 1.83, log NBi ≤ 0.80, log NTh = 0.82, and log NU ≤ 0.60. The meaning of these new solar abundances is discussed from the point of view of the nucleosynthesis theories. © 1969 D. Reidel Publishing Company.