We report a new technique for the measurement of short lifetimes (${10}^{-14\mathrm{}}$ sec) of innershell vacancies in heavy-ion projectiles moving through thin, solid targets. The technique is applicable whenever the yield of projectile x rays does not increase in proportion to target thickness. Lifetime values of 1.5×${10}^{-14\mathrm{}}$ and 3.3×${10}^{-14\mathrm{}}$ sec have been found for $K\alpha$ and $K\beta$ transitions, respectively, in highly stripped sulfur ions.

• Received 4 February 1974

DOI:https://doi.org/10.1103/PhysRevLett.33.807