'Universal' representation of HPGe detector efficiencies

By fitting a simple 4-parameter function to twelve sets of HPGe detector efficiency measurements, an approximate 'universal' expression good to ±15% is obtained for HPGe absolute full-energy-peak efficiencies as a function of photon energy between ∼125 and ∼1750 keV for a ∼4-to-1 range of crystal volumes and for coaxial and planar crystal shapes.