Half-lives of Au, Hg, and Pb isotopes from photoactivation

The ground state half-lives of the gold isotope ¹⁹⁶Au, the mercury isotopes ^195,197,203Hg, the lead isotope ²⁰³Pb, and the half-lives of two isomers in ¹⁹⁹Hg and ²⁰⁴Pb have been measured with high precision using the photoactivation technique. The γ-ray activity was counted over several half-lives with high-purity germanium detectors. The measured half-lives are: T_1/2(¹⁹⁶Au)=6.1669+/-0.0006 d; T_1/2(¹⁹⁵Hg)=10.53+/-0.03 h; T_1/2(¹⁹⁷Hg)=64.94+/-0.07 h; T_1/2(²⁰³Hg)=46.6+/-0.1 d; T_1/2(²⁰⁴Pb)=51.95+/-0.01 h; T_1/2(^199mHg)=42.67+/-0.09 min; T_1/2(^204mPb)=1.14+/-0.04 h.