The degree of paraxiality (DOP) of an electromagnetic fractional multi-Gaussian Schell-model (EM-FMGSM) beam is discussed, and the effect of the properties of the light source on its DOP is also studied. It is shown from the numerical results that the DOP of an EM-FMGSM beam is determined by the rms widths of the auto-correlation functions, the truncated parameter, the degree of polarization, and the boundary characteristics of its source. Moreover, the far-field divergence angle of the beam source is also investigated to illustrate the behaviors of the DOP.

中文翻译：

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电磁分数阶多高斯 Schell 模型光束的近轴度

讨论了电磁分数多高斯谢尔模型(EM-FMGSM)光束的近轴度(DOP)，并研究了光源特性对其DOP的影响。数值结果表明，EM-FMGSM 波束的 DOP 由自相关函数的均方根宽度、截断参数、偏振度及其源的边界特性决定。此外，还研究了光束源的远场发散角以说明 DOP 的行为。