Energy optimization procedure for treatment planning with laser-accelerated protons.

Area of Science:

• Physics
• Particle Acceleration
• Medical Physics

Background:

• Laser-driven proton acceleration offers a novel approach for particle therapy.
• Achieving precise dose distributions, like spread-out-Bragg peaks (SOBP), is crucial for effective proton therapy.
• Current methods for calculating SOBP distributions require accurate proton energy spectra.

Purpose of the Study:

• To develop a simple analytical model for predicting the proton spectrum required for SOBP.
• To facilitate the calculation of energy and intensity modulated proton dose distributions.
• To establish an optimal relationship between energy sampling and initial proton energy width.

Main Methods:

• Solving the Boltzmann kinetic equation for the proton distribution function.
• Deriving an analytical expression for SOBP proton energy spectra.
• Analyzing the impact of beamlet size and modulation depth on energy spectra.

Main Results:

• A simple analytical model accurately predicts the necessary proton spectrum for SOBP.
• The model allows calculation of SOBP spectra for various beamlet sizes and modulation depths.
• An optimal relationship between energy sampling size and initial proton energy distribution width was identified.

Conclusions:

• The developed analytical model provides a straightforward method for determining proton spectra for SOBP.
• This model is directly applicable to calculating modulated proton dose distributions in therapy.
• Understanding the relationship between energy sampling and initial energy width is key for practical implementation.