Theoretical lifetimes and oscillator strengths in CeII. Application to thechemical composition of the Sun

A new set of transition probabilities is derived for many transitions of Ce II of astrophysical interest. A relativistic Hartree-Fock method, combined with a least-squares fitting of the available experimental levels, includi ng a number of newly determined values, has been used for the determination of the eigenfunctions and eigenvalues. Configuration interaction and core- polarization effects have been introduced in the calculations. The derived oscillator strengths lead to a new value of the cerium abundance in the sol ar photosphere, A(Ce) = 1.70 +/- 0.04 (in the usual logarithmic scale) whic h is somewhat larger but in reasonable agreement with the meteoritic result .