Using stable distributions to characterize proton pencil beams.

Area of Science:

• Medical Physics
• Radiation Oncology
• Computational Physics

Background:

• Proton therapy offers precise dose delivery.
• Accurate modeling of proton beam transport is crucial for treatment planning.
• Current methods may require extensive commissioning data.

Purpose of the Study:

• To introduce and evaluate stable distributions for quantifying proton pencil beam behavior.
• To develop a robust methodology for modeling proton beam propagation in a medium.
• To assess the efficacy of stable distributions compared to existing methods.

Main Methods:

• Monte Carlo simulations (FLUKA) replicated clinical proton pencil beams.
• Stable distribution methodology characterized beam lateral spread and energy deposition.
• Parameters (α, γ, β) described beam profiles and their depth variation.

Main Results:

• Stable distributions showed good quantitative fit, comparable to double Gaussian models, except at highest energies.
• Meta-parameterization enabled interpolation of unmeasured beam data from limited commissioning.
• The method successfully described symmetric and asymmetric beam profiles.

Conclusions:

• Stable distributions are well-suited for describing proton pencil beam propagation.
• This methodology provides a powerful tool for quantifying beam behavior in various media.
• The approach can potentially reduce the commissioning effort for proton therapy facilities.