Technical Note: SpekPy v2.0-a software toolkit for modeling x-ray tube spectra.

Area of Science:

• Medical Physics
• Computational Physics
• Radiological Sciences

Background:

• Accurate modeling of x-ray spectra is crucial for radiation therapy and diagnostic imaging.
• Existing tools may have limitations in material scope or physical phenomenon modeling.
• SpekPy provides an open-source solution for simulating x-ray tube spectra.

Purpose of the Study:

• To describe advances in SpekPy version 2.0 (v2), focusing on expanded target materials and enhanced anode heel effect modeling.
• To demonstrate the practical application and validation of the SpekPy toolkit.
• To compare different physics models within SpekPy for spectral prediction accuracy.

Main Methods:

• SpekPy v2 predictions were compared against experimentally measured spectra for tungsten and molybdenum targets.
• The software's ability to model tube output variations with potential was assessed using CT scanner data.
• On-axis and off-axis spectral predictions were evaluated using different physics models (casim, kqp).

Main Results:

• SpekPy v2 demonstrated close agreement (within 2%) with experimental spectra for various tube potentials.
• CT scanner spectral output predictions showed good correlation (within 4%) across a range of kilovoltages.
• The kqp model offers higher accuracy for anode heel effect modeling, including bremsstrahlung anisotropy.

Conclusions:

• SpekPy v2 reliably predicts both on- and off-axis x-ray spectra for tungsten and molybdenum targets.
• The toolkit's open-source MIT license facilitates integration into various research and clinical projects.
• SpekPy v2 is a valuable and accessible tool for researchers and professionals in radiological sciences.