Abstract We consider an input ion beam that has Gaussian distributions of the initial ion coordinates and transverse velocities at the entrance of a quadrupole mass filter (QMF) with round rods. To calculate the statistical QMF acceptance, an ion trajectory method has been used. The probability density functions of accepted points on phase planes of transverse ion positions and velocities in the X and Y directions are used to visualize the distributions of phase space points. To determine the statistical acceptances we calculate the second moments of the probability density functions. We define the statistical acceptance of the quadrupole mass filter as the area of an ellipse on the phase plane determined by the second moments. The values of the second moments characterize the efficiency of the coupling of the Gaussian ion source and the acceptance of a quadrupole rod set with round rods. The above approach is a supplement to a previously published theoretical model of QMF fields with circular electrodes.

中文翻译：

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用圆棒将高斯输入光束耦合到四极杆质量过滤器

摘要 我们考虑输入离子束，该离子束在带圆杆的四极杆质量过滤器 (QMF) 入口处具有初始离子坐标和横向速度的高斯分布。为了计算统计 QMF 接受度，使用了离子轨迹方法。X 和 Y 方向横向离子位置和速度的相平面上可接受点的概率密度函数用于可视化相空间点的分布。为了确定统计接受度，我们计算概率密度函数的二阶矩。我们将四极杆质量过滤器的统计接受度定义为由二阶矩确定的相平面上椭圆的面积。二阶矩的值表征了高斯离子源的耦合效率和带圆杆的四极杆组的接受度。上述方法是对先前发表的圆形电极 QMF 场理论模型的补充。