  Radiative lifetimes, accurate to +/- 5%, have been measured for 212
odd-parity levels of Sm II using laser-induced fluorescence. The lifetimes are
combined with branching fractions measured using Fourier-transform spectrometry
to determine transition probabilities for more than 900 lines of Sm II. This
work is the largest-scale laboratory study to date of Sm II transition
probabilities using modern methods. This improved data set has been used to
determine a new solar photospheric Sm abundance, log epsilon = 1.00 +/- 0.03,
from 26 lines. The spectra of three very metal-poor, neutron-capture-rich stars
also have been analyzed, employing between 55 and 72 Sm II lines per star. The
abundance ratios of Sm relative to other rare earth elements in these stars are
in agreement, and are consistent with ratios expected from rapid
neutron-capture nucleosynthesis (the r-process).
