Selected lifetime and oscillator strength measurements in Si II

We have remeasured the lifetimes of the 3s(2)4s and 3s(2)5s(2)S(1/2) levels in Si II using beam foil spectroscopic techniques. Measured values for the lifetimes and oscillator strengths derived from them are presented and com pared with previous measurements and theoretical calculations. Agreement wi th recent theoretical calculations is now quite good: for 3s(2)4s it is exc ellent and for 3s(2)5s it is satisfactory, although the theoretical uncerta inties in that calculation are still somewhat larger than desired.