Atomic charge states of residual nuclei from compound nucleus reactions

The average energy-to-charge state ratios of evaporation residues from fusion of Ni+Sn are measured using an electrostatic deflector combined with E-E particle identification. The deduced average atomic charge states are 5 to 13 units higher than the equilibrium values expected from stripping in the target, suggesting that nuclear decays outside the target foil play an important role. The importance of internal conversion in determining these anomalously high charge states is discussed. NUCLEAR REACTIONS Sn114,124 (Ni58, fusion); Elab=281 MeV; measured (Eq); evaporation residues; deduced average atomic charge states; discussed role of internal conversion, implications for superheavy nuclei searches.