Multistage laser-plasma acceleration of ultrashort electron and positron bunches

We propose a variant of multistage electron acceleration based on a multichannel laser facility with a peak laser pulse power of up to 15 PW in one channel. In contrast to strongly nonlinear acceleration regimes with the presence of electron density cavitation on the radiation propagation axis, the proposed moderately nonlinear regime will make it possible to achieve not only sufficiently high energies (60–100 GeV in three to five accelerator stages), but also a high quality of accelerated electron bunches (relative energy spread is no more than 1%, and normalised emittance is no more than 1 mm·mrad), which is important for numerous applications, such as precision tests of the Standard Model, experiments on quantum electrodynamics (generation of electron&ndash:positron pairs), and experiments on the development of high-power sources of short-wavelength (gamma quanta) radiation. The implementation of the project will make it possible to closely approach the studies, which are important for the development of theory and modern practical applications. A preliminary analytical analysis and numerical simulation confirm the achievability of the indicated parameters of electron bunches in the case of the implementation of the proposed project.