HB2025 - the 71st ICFA Advanced Beam Dynamics workshop on High-Intensity and High-Brightness Hadron Beams

Broadband capture and achromatic focusing of laser-driven protons for RF linac post-acceleration

THPT11

Oct 23, 2025, 3:30 PM

2h

third floor (conference center)

Poster Presentation WGB:Beam Dynamics in Linacs THPT poster session

Speaker

Haoyu Zhou (Institute of Modern Physics, Chinese Academy of Sciences)

Description

Laser-driven proton sources produce ultra-short, high-current pulses ideal for FLASH radiotherapy but lack therapeutic energy levels. Bridging this energy gap via RF linac post-acceleration faces critical beam transport challenges due to wide angular divergence and broad energy spreads intrinsic to laser protons. This work analyzes how large energy spreads constrain RF bunching and capture dynamics, introducing unique trade-offs that determine optimal frequency selection and longitudinal placement.​​ We also developed linear focusing schemes that exploit buncher-generated energy modulation to compensate chromatic aberrations. Beam dynamics simulations for 7 MeV laser protons confirmed simultaneous broadband energy capture and achromatic focusing, achieving >5 times the transport efficiency of previous post-acceleration designs with S-band cavities. These results validated design strategies for laser-RF hybrid proton linacs targeting future high-efficiency medical accelerators.