The Belle II detector of the SuperKEKB collider in Japan was designed and built by an international team of over 750 physicists from 25 countries. In this grand project, a research team from the Moscow Institute of Physics and Technology (MIPT) and Lebedev Physical Institute of the Russian Academy of Sciences was responsible for one of the most important Belle II subsystems — the detector of long-lived neutral kaons, KL-mesons, and muons.
Photo. Belle II detector. Credit: N. Toge/KEK
For the first time in eight years, KEK will begin colliding the electron and positron beams with a brand new positron damping ring and the Belle II detector since the previous KEKB collider ceased its operations in 2010.
Over the years, KEKB and its Belle detector have confirmed that the symmetry of charge and parity in the interactions of some particles and antiparticles is actually broken, and revealed the properties of several important fundamental processes in particle physics.
“After more than 10 years of experiments, it became clear: New scientific breakthroughs are impossible unless a much more powerful machine becomes available. The accelerator was in need of a major upgrade that would enable a 10 times higher luminosity,” says Tagir Aushev, the head of the Laboratory of High Energy Physics at MIPT. “However, this also meant that the detector had to be enhanced to keep up with the high-energy experiments.”
SuperKEKB, along with the Belle II detector, is a facility designed to search for new physics beyond the Standard Model by measuring rare decays of elementary particles such as b quarks, c quarks, and tau leptons.
In contrast to the LHC at CERN in Geneva, Switzerland, which is the world’s highest-energy hadron accelerator, SuperKEKB/Belle II, located at the High Energy Accelerator Research Organization in Tsukuba, Japan, is designed to achieve unmatched luminosity — 40 times greater than that of its predecessor, the KEKB machine, which holds many records for accelerator performance.
On March 21, 2018, a beam of electrons was successfully stored in the main ring. A beam of positrons will be injected and stored around the beginning of April, following which final accelerator tuning for beam collisions will begin. The first collisions of electrons and positrons are expected in the coming months.
“This next phase in the operation of the collider opens up opportunities for new discoveries,” adds Tagir Aushev.