Use of 169Yb as a calibration standard

The energies and intensities of the gamma and X-rays in the decay of 169Yb (32 d) have been measured with a low energy photon spectrometer (LEPS) and a high purity germanium (HPGe) detector. This source is recommended for use as a standard for low-energy efficiency calibration of such detectors. It is also proposed to use this source as a standard for conversion electrons, as the multipolarities and mixing ratios are well known for most strong transitions.