High-precision efficiency calibration of a high-purity co-axial   germanium detector
  A high-purity co-axial germanium detector has been calibrated in efficiency to a precision of about 0.15% over a wide energy range. High-precision scans of the detector crystal and gamma-ray source measurements have been compared to Monte-Carlo simulations to adjust the dimensions of a detector model. For this purpose, standard calibration sources and short-lived on-line sources have been used. The resulting efficiency calibration reaches the precision needed e.g. for branching ratio measurements of super-allowed beta decays for tests of the weak-interaction standard model. 
B. Blank, J. Souin, P. Ascher, L. Audirac, G. Canchel, M. Gerbaux, S.   Grevy, J. Giovinazzo, H. Guerin, T. Kurtukian Nieto,...
physics.ins-det nucl-ex