对２５ＭｅＶ／ｕ４０Ａｒ＋９３Ｎｂ反应形成的热核发射的γ射线、轻带电粒子和蒸发余核进行了符合测量，从余核的飞行时间和轻带电粒子能谱得出非完全熔合反应形成的热核的初始激发能．ＧＤＲγ衰变的产额在研究的激发能范围内保持不变。用统计模型ＣＡＳＣＡＤＥ程序对实验结果进行分析。讨论了引起ＧＤＲγ衰变产额饱和的原因。当假定热核激发能大于２５０ＭｅＶ时无ＧＤＲγ发射，则可以用ＣＡＳＣＡＤＥ程序很好地拟合Ｅγ大于１２ＭｅＶ的实验谱。 The coincidence measurements of γ-rays, light-charged particles and evaporated residual nuclei formed by the thermonuclear reactions of 25MeV / u40Ar + 93Nb were carried out. From the time of flight and the spectra of light charged particles, the initial nuclei formed by incomplete fusion reaction Excitation energy. The yield of GDRγ decay remains constant over the excitation energy range studied. The statistical model CASCADE program was used to analyze the experimental results. The reason for the saturation of GDR gamma decay is discussed. An experimental spectrum with Eγ greater than 12 MeV can be well fit with the CASCADE program when assuming that there is no GDRγ emission when the thermonuclear excitation energy is greater than 250 MeV.