Three double-ring B factories—PEP-II, KEKB, and SuperKEKB—were built with asymmetric beam energies to produce high luminosity at the Υ(4S) resonance producing copious B mesons and associated particle physics data, delivered to their respective particle physics detectors, BaBar, Belle, and Belle II. In PEP-II and KEKB, the primary goal was achieved to make the first measurements of charge parity (CP) violation in decays in the B meson system. PEP-II and KEKB have finished beam operations, but particle data analysis continues. SuperKEKB is extending those measurements. The beam operation of SuperKEKB with Belle II has recently started. These three accelerators have pushed the state of the art of accelerators of two-ring colliders, including small beam emittances, small interaction point beam sizes, large stored beam currents, crab cavities, top-up injection with the detectors on, bunch-by-bunch feedbacks, crab waist operation, high beam–beam parameters, high peak luminosity, and high integrated luminosity.

中文翻译：

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高亮度 B Factory e+e− 碰撞体


三个双环 B 工厂——PEP-II、KEKB 和 SuperKEKB——用不对称的束流能量建造，以在 Υ（4S） 共振下产生高光度，产生大量的 B 介子和相关的粒子物理数据，并传送到它们各自的粒子物理探测器 BaBar、Belle 和 Belle II。在 PEP-II 和 KEKB 中，实现了主要目标，即首次测量 B 介子系统中衰变中的电荷奇偶性 （CP） 违例。PEP-II 和 KEKB 已经完成了光束操作，但颗粒数据分析仍在继续。SuperKEKB 正在扩展这些测量。带有 Belle II 的 SuperKEKB 的梁操作最近已经开始。这三个加速器推动了双环对撞机加速器的最新技术，包括小光束发射度、小交互点光束尺寸、大存储光束流、蟹腔、探测器开启时的补足注入、逐束反馈、蟹腰操作、高光束参数、高峰值亮度和高积分亮度。