We report lifetimes, branching fractions, and the resulting oscillator strengths for transitions within the P II multiplet (3s23p2 3P - 3s3p3 3Po) at 1308 {AA}. These comprehensive beam-foil measurements, which are the most precise set currently available experimentally, resolve discrepancies involving earlier experimental and theoretical results. Interstellar phosphorus abundances derived from {lambda}1308 can now be interpreted with greater confidence. In the course of our measurements, we also obtained an experimental lifetime for the 3p4s 3P0o level of P IV. This lifetime agrees well with the available theoretical calculation.
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