On a possibility to construct a high luminosity 2 × 5 GeV photon collider at SLC

Abstract

Physical principles of operation of the high energy photon linear colliders (PLC) based on the Compton backscattering of laser photons on high energy electrons are discussed. The main emphasis is put on the analysis of a possibility to construct the PLC with the center of mass energy 3–10 GeV at the Stanford Linear Collider (SLC) facility. It is shown that it can be done with minor modifications of the existing facility by installation of new injector, kicker magnet and two-stage free electron laser. Proposed FEL system consists of a tunable FEL oscillator (λ ∼ 10–30 μm, output power ∼ 10 MW) with subsequent amplification of the master signal in a FEL amplifier up to the power ∼ 3 × 10 11W. The FEL parameters are optimized, restrictions on the electron beam and FEL magnetic system parameters are formulated and the ways of the possible technical realization are discussed. It is shown that the FEL based photon collider at SLC, providing luminosity of colliding γγ beams L γγ ∼ 10 34 cm −2 s −1, may be constructed at the present level of acceleration technique R&D. It will be a unique instrument for precision studying of the charmonium and bottomonium physics as well as τ-lepton physics providing ∼10 2 polarized τ-leptons per second. At the same time the photon linear collider at SLC will serve as a reliable test base for constructing the future TeV-range photon linear colliders.