Nine “single energy” gamma standard solutions are used to calibrate the peak and total efficiencies. True coincidence summing(TCS) corrections in γ spectrum analysis of 60Co、152Eu and 154Eu in cylindrical volume soil samples measured on the top of a HPGe detector with 100% relative efficiency have been studied. The experimental TCS correction factors have been measured by comparing the calibrated efficiency function after correction for self absorption and the efficiencies measured by using standard soil so...