在直线加速器中纵向高斯型密度分布的假定下，推得了纵向高斯型密度分布与横向密度分布分别为均匀型（Ｋ－Ｖ）、水袋型（ＷＢ）、抛物线型（ＰＡ）和高斯型（ＧＡ）相组合情况下的非均匀密度分布的自场能公式及相应的束流发射度增长；并且通过数值计算，给出了束团自场能及发射度随加速器和束团参数变化的图表。 Under the assumption of longitudinal Gaussian density distribution in linear accelerator, the longitudinal Gaussian density distribution and transverse density distribution are deduced as K-V, WB, PA and Gaussian GA), and the corresponding beam current emissivity increase. The graph of the self-field energy and the emissivity of the beam with the accelerator and the beam-group parameters is given by numerical calculation.