Abstract
The L-shell X-ray relative intensities I(Lalpha )/I(Ll), I(Lalpha )/I(Lbeta ) and I(Lalpha )/I(Lgamma ) for U, Th, Pb and the ratios I(Lalpha +l)/I(Lbeta ) and I(Lalpha +l)/I(Lgamma ) for W have been measured. The L-shell electrons are excited by 59.57 keV gamma rays from 241Am and the fluorescent L-shell X-ray intensities are measured with a Si(Li) detector. The experimental results are found to agree well with theory.