Status of the Novosibirsk Phi-Factory project

The Novosibirsk, Institute of Nuclear Physics develops the project of a complex electron-positron colliding beam facility, which comprises: a 4x7 GeV B-factory with a luminosity of 5·1033 cm-2 s-1; a var-phi-factory with a luminosity of over 1033 cm-2 s-1; an injector consisting of a linear accelerator and a storage ring for providing the factories with intense electron and positron beams. The var-phi-factory is a new generation facility with colliding e+ e- beams in the energy range of the var-phi-meson resonance (1,020 MeV). The first stage of the project envisages the var-phi-factory performance in a single bunch mode on the basis of one storage ring with an attainable luminosity of Lmax∼1·1033cm-2s-1. This level of luminosity is a threshold one for experiments on measuring constants of CP violating interactions. Besides, the scope of experiments on the study of exotic decay modes of ρ-, ω-, var-phi-mesons becomes practically unlimited. After investigation the relevant problems of accelerator physics and running the first cycle of experiments with the CMD-3 detector the second stage of the project will come into force. It will be devoted to increasing the luminosity. To attain this the magnetic structure and the storage ring design provide for a 3-bunched beam regime applying the electrostatic beam separation at the side interaction points (IP). Besides, an alternative scheme of multi-bunch regime is considered based on two independent electron and positron storage rings with electrostatic convergence of the beams at one IP