the drifting problems of gamma ray spectra caused by the factors such as temperature variance
long measuring period and so on have been studied. Based on the steady energy and shape of a gamma photopeak
a method of searching peak and stabilizing spectrum is presented.Considering the photopeak as a criterion and the discriminating threshold as an adjustable object
the system is operated directly on the energy orientation of the energy windows measured
to ensure the stability of relative energy of the windows.