{'fraction_non_alphanumeric': 0.027950310559006212, 'fraction_numerical': 0.0, 'mean_word_length': 4.825301204819277, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Storage Ring Optics Measurement, Model, and Correction

To improve the optics of a storage ring, it is very helpful if one has an accurate lattice model. Although the ideal lattice may serve such a purpose to some extent, in most cases, real accelerator optics improvement requires accurate measurement of optics parameters. In this section, we present precision measurements of a complete set of linear orbits from which we can form a linear optics model to match the linear optics of the real machine. We call such a model a virtual machine. We have used a model-independent analysis (MIA) for accurate orbit and phase advance measurement and then used an SVD-enhanced Least Square fitting for building accurate virtual models for PEP-II e+, e- storage rings. The MIA virtual machine matches very well the real-machine linear optics including dispersion. It has successfully improved PEP-II beta beats, linear couplings, half-integer working tunes, and dispersion.