Energy Levels ofBi211

Abstract

The gamma-ray spectrum from the decay of ${\mathrm{Pb}}^{211}$ has been studied with NaI crystals (using singles, gamma-gamma coincidence, and sum-coincidence techniques) and with a germanium semiconductor detector. The energies and relative gamma-ray intensities are reported for 16 transitions in ${\mathrm{Bi}}^{211}$. The energy and relative intensity of 5 internal-conversion electron lines were measured with a precision magnetic betaray spectrometer. From the gamma-ray and internal-conversion transition energies and the gamma-gamma coincidence measurements a consistent level diagram for ${\mathrm{Bi}}^{211}$ is proposed which has levels at 404.84±0.04, 766.34±0.07, 831.83±0.04, 1020±3, 1076±3, 1104±2, 1188±2, and 1265±2 keV.