We present an analysis of data published recently on coherent optical transition radiation interferometry (COTRI) angular distributions made on the Argonne experiment on microbunching. These COTRI distributions exhibited some intriguing characteristics: highly enhanced lobe patterns in the /spl plusmn//spl theta//sub y/ direction, instead of circularly symmetric fringes; and asymmetries in intensities in +/spl theta//sub y/ vs. -/spl theta//sub y/ in some cases. We have done calculations that produce patterns consistent with those observed. The role of the microbunch's elliptical transverse beam profile in accounting for the /spl theta//sub x/-/spl theta//sub y/ asymmetry is illustrated. Similarly, a beam profile with a /spl plusmn/y asymmetry gives a lobe asymmetry in +/spl theta//sub y/ vs. -/spl theta//sub y/. The interplay of the interference fringe pattern and the microbunch's transverse form factor accounts for the angular positions of the lobes. The fringe visibility was calculated by convolving the beam divergence distribution with the COTRI pattern. Thus, we have shown that COTRI angular patterns can be used to characterize the effective transverse size, microbunch length, divergence, and the bunching fraction.
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机译：我们对最近发表的有关微束聚光的Argonne实验上进行的相干光学跃迁辐射干涉测量（COTRI）角分布的数据进行分析。这些COTRI分布表现出一些吸引人的特征：/ spl plusmn // spl theta // sub y /方向上的叶模式高度增强，而不是圆对称条纹;在某些情况下+ / spl theta // sub y /与-/ spl theta // sub y /的强度不对称性。我们进行的计算得出的模式与观察到的模式一致。说明了微束的椭圆形横束轮廓在解决/ spl theta // sub x /-/ spl theta // sub y /不对称方面的作用。类似地，具有/ spl plusmn / y不对称性的光束轮廓在+ / spl theta // sub y /与-/ spl theta // sub y /中给出了波瓣不对称性。干涉条纹图案和微束的横向形状因子的相互作用解释了瓣的角位置。通过将光束发散分布与COTRI图案进行卷积，可以计算出条纹的可见性。因此，我们已经表明，可以将COTRI角度模式用于表征有效的横向尺寸，微束长度，发散度和聚束分数。
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