SuperKEKB
From Wikipedia, the free encyclopedia
SuperKEKB[1] is a particle collider located at KEK (High Energy Accelerator Research Organisation) in Tsukuba, Ibaraki Prefecture, Japan. SuperKEKB collides electrons with positrons at the centre-of-momentum energy close to the mass of the Υ(4S) resonance making it a second-generation B-factory for the Belle II experiment. The accelerator is an upgrade to the KEKB accelerator, providing approximately 40 times higher luminosity,[2] due mostly to superconducting quadrupole focusing magnets.[1] The accelerator achieved "first turns" (first circulation of electron and positron beams) in February 2016.[3] First collisions occurred on 26 April 2018.[4] At 20:34 on 15 June 2020, SuperKEKB achieved the world’s highest instantaneous luminosity for a colliding-beam accelerator, setting a record of 2.22×1034 cm−2s−1.[5]