The rates of several electric-dipole forbidden decays of 3p and 3d levels in Cl-, S-, P-and Si-like ions of Fe have been measured optically at a heavy-ion storage ring. In several cases, more than one decay contributes to a given decay curve, which complicates the analysis. The lifetime results, with a precision range from 0.6 to 20%, compare well with some theoretical predictions, but are more precise. They are also more precise than some experimental data from an electrostatic ion trap.

Radiative lifetime measurements were performed with time-resolved laserinduced fluorescence techniques for 47 levels of the astrophysically important ion Sm 1+ over the energy range 21 000-36 000 cm −1 . The new results have been compared with previous measurements but also with theoretical calculations taking configuration interactions and core-polarization effects into account, and a satisfying agreement has been found for many levels of this complex ion. New calculated transition probabilities are deduced from the experimental lifetimes and from the theoretical branching fractions for 162 transitions of astrophysical interest. These results will help astrophysicists in the quantitative investigation of the chemical composition of CP stars.

Natural radiative lifetimes have been measured for three odd‐parity levels of neutral lead using time‐resolved UV laser‐induced fluorescence from a laser‐produced plasma. These new lifetimes, as well as additional recent values obtained by laser spectroscopy, combined with theoretical branching ratios deduced from a relativistic Hartree–Fock calculation taking core polarization effects into account, have allowed the deduction of a new set of accurate f‐values of astrophysical interest. Using the new lifetime value for 6p7s (1/2, 1/2)°0, a refined value of the lead abundance in the solar photosphere is deduced: APb= 2.00±0.06 on the usual logarithmic scale, allowing the resolution of the long‐standing discrepancy previously observed between the solar photosphere and meteorites.

Radiative lifetimes of seven excited states of Er iii have been measured using time‐resolved laser‐induced fluorescence following two‐photon excitation. Relativistic Hartree–Fock calculations taking core‐polarization effects into account are found to be in excellent agreement with the experimental results. A large set of new calculated transition probabilities is presented for many transitions of astrophysical interest. These results will be useful for investigating the composition of chemically peculiar stars.

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