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[sub -50][sup +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. © 2003 American Institute of Physics [ABSTRACT FROM AUTHOR]