Budker Institute of Nuclear Physics

The proposed complex is to comprise

• Two-ring e+e- collider
• Linear accelerator for full energy
• Positron injector
• Polarized electron injector

Electron-Positron super c-tau factory will operate at total energies from 2 to 5 GeV with unprecedented high luminosity of 10³⁵ cm^-2s^-1 and the longitudinal polarization of the electrons at the interaction area. The main purpose of the experiments at the collider is search for effects of CP-violation in the decays of charmed particles, tests of the Standard Model in the decay of the tau lepton, the search and study of an entirely new form of matter: glueballs, hybrids, etc. The data, which are planned to record, by 3-4 orders exceed everything that has been recorded so far in any other experiment.

Now, the only realized project of e+e- collider with high luminosity in this energy region is the collider BEPC II, launched in 2009 in Beijing laboratory IHEP, with the planned peak luminosity of 10³³ cm^-2s^-1.

The development of this project in the BINP SB RAS is connected, first, with the outstanding results that have been obtained on the B-factories in the laboratory KEK (Japan) and SLAC (USA). The high luminosity of the B-factories allowed, using the radiative return, some interesting results in the field of energy c-tau factories, though the creation collider aimed at the study of the physics of charmed particles and the tau lepton is still an extremely important task.

Second, the growth of interest in the creation of the c-tau factory of next generation was caused by the discovery of a new method of beam collision in the electron-positron collider (Crab Waist), which allows without significant increasing of the beam intensity, the machine size or reduce the length of the bunch, acheive the luminosity by comparing with the existing factories directly up to two orders of magnitude.

Realisation of the program will require the physical development of a universal magnetic detector with high momentum resolution for charged particles, limiting the energy resolution of photons, record parameters of particle identification, and data collection system that can handle events with a frequency of 300-400 kHz.