Evidence for the Identification of 178Pb

With the use of the Berkeley Gas‐filled Separator, the α decay of 178Pb was identified in 78Kr irradiations of 102Pd. Following their separation from the incident beam particles, reaction products were implanted in a position‐sensitive silicon detector. Two events with Eα of 7602 and 7629 keV were observed and assigned to 178Pb because they were position‐correlated with known descendants in the 174Hg α‐decay chain. The half‐life of 178Pb was calculated with the maximum likelihood method to be 122−50+290 μs. A mass excess of 3608(39) keV and a proton separation energy of 362(48) keV were deduced for 178Pb based on the known masses of 174Hg and 177Tl.