Accurate Beam Spot Fitting Algorithm Using Generalized and Skewed Gaussian Type Distributions

To address non-standard Gaussian beam spot pro-files in injectors, this paper proposes a fitting algo-rithm based on Gaussian, the newly introduced Gener-alized Gaussian Type and Skewed Gaussian Type dis-tributions. These distributions are specifically de-signed to better fit non-Gaussian and asymmetric beam spots by automatically selecting the most suitable model. Validation using beam spot images from the YAG screen after the electron gun in the Hefei Light Source II (HLS-II) injector demonstrates that the Gen-eralized Gaussian Type is effective for fitting sharp or broad profiles, while the Skewed Gaussian Type is well-suited for handling asymmetry. Compared to tra-ditional methods, the proposed algorithm improves fitting accuracy and adaptability, providing a practical solution for complex beam measurement challenges.