Start-to-end modelling of laser-plasma acceleration, beam transport and dose deposition of very high-energy electrons for radiotherapy.

The proposed radiotherapy using very high-energy electron (VHEE) beams generated by a laser-plasma accelerator has garnered significant interest due to its dose distribution capabilities and potential to address limitations of traditional photon-based radiotherapy. To explore the feasibility of such an approach, we develop a start-to-end simulation workflow to model VHEE radiotherapy from the electron source through the beamline to dose delivery in the target. The presented study uses the parameters of OONA, the commercial <1.3 J, <25 fs pulse duration laser recently installed at the Weizmann Institute of Science. Through particle-in-cell simulations of laser-plasma interaction, realistic electron beams are obtained. A beamline consisting of quadrupoles, a collimator, and dipoles is then used to collimate and filter the beams and arrange them into a beam array. Using GEANT4 simulations, we calculate the dose deposition in water phantoms and heterogeneous phantoms with bone inserts. Multifield irradiation setup and the dose distribution at the isocenter through different incidence angles are studied, simulating multi-angle conformal delivery. Our findings demonstrate that polychromatic VHEE beams generated from laser-plasma accelerators, when delivered through such a beamline, can achieve favorable dose distribution for reaching areas deep inside the phantom. This study highlights the potential of the developed start-to-end workflow for exploring and optimizing LPA-generated VHEE radiotherapy, paving the way for further research and potential clinical implementation.