The Doppler shift attenuation method (DSAM) to measure lifetimes in the region 10 −14−10 −11 s following a heavy ion induced fusion evaporation reaction has the uncertainty that the side feeding time is unknown and it is of the same order of magnitude as the lifetimes measured in DSAM. The present paper describes a method of measuring lifetimes of the nuclear states eliminating the side feeding, as well as giving information about this feeding. The 40Ar( 9Be, 3n) 46Ti reaction was used as an example to test the method. A lifetime of τ = (0.73±0.14) ps was deduced for the 4893 keV (8 +) state in 46Ti and the side feeding time was estimated to be 0.5–0.9 ps.