High-Quality electron bunch production for high-brilliance Thomson Scattering sources

摘要

Laser Wake Field accelerated electrons need to exhibit a good beam-quality to comply with requirements of FEL or high brilliance Thomson Scattering sources, or to be post-accelerated in a further LWFA stage towards TeV energy scale. Controlling electron injection, plasma density profile and laser pulse evolution are therefore crucial tasks for high-quality e-bunch production. A new bunch injection scheme, the Resonant Multi-Pulse Ionization Injection (RMPII), is based on a single, ultrashort Ti:Sa laser system. In the RMPII the main portion of the pulse is temporally shaped as a sequence of resonant sub-pulses, while a minor portion acts as an ionizing pulse. Simulations show that high-quality electron bunches with energies in the range 265MeV - 1.15GeV, normalized emittance as low as 0.08 mm-mrad and 0.65% energy spread can be obtained with a single 250 TW Ti:Sa laser system. Applications of the e-beam in high-brilliance Thomson Scattering source, including 1.5 - 26.4 MeV γ sources with peak brilliance up to 1 • 10~(28)ph/(s • mm~2 • mrad~2 • 0.1 % bw), are reported.