Belle, BelleⅡ Experiment   / High Energy Accelerator Research Organization（KEK）

 Belle, BelleII experiment is a high energy accelerator experiment using electron and anti-electron beam. Belle II is the successor of the Belle experiment and is running with a SuperKEKB accelerator and Belle II detector. SuperKEKB accelerator built to remodel the KEKB accelerator that has been operating since 1999 to increase beam collision performance by 40 times. The energy of electron and anti-electron was changed to 7 GeV and 4 GeV, respectively. Collision performance is greatly enhanced by narrowing the beam down to the nanometer level of collision. With the modification of the accelerator, the detector was also upgraded. Belle II detector was upgraded from Belle detector. All internal sensors were replaced with new ones to improve performance.
 Belle II is an international collaboration team based on Belle and consists of approximately 900 researchers from 26 countries and regions and 113 universities and research institutes (as of November 2018). They collaborate on data collection and physics analysis. In the Belle II experiment, we work for analyzing the data in a high-precision region (luminosity frontier) with 50 times that accumulated in the Belle experiment and reproducing symmetry breaking in B mesons and extremely rare phenomena that should have occurred in the early universe. From these studies, we can uncover the properties of unknown particles and forces and contribute to discovering new laws of physics.

Homepage of Belle II experiment
Homepage of Super KEKB
Homepage of KEK