Dear FLUKA Support Team,
I am simulating dose distributions in FLUKA using CT images and would like to confirm whether my method for converting Hounsfield Units (HU) to material composition, mass density, and electron density aligns with FLUKA’s internal mechanisms.
1. HU-to-Material Mapping
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HU ranges are mapped to predefined materials with specific elemental compositions and mass densities (e.g., for 700 ≤ HU < 800: H, C, N, O, Na, P, S, Mg, Ca. mass density: 1.460408 g/cm3).
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Total Mass Density Calculation : For each voxel, linear interpolation is applied between adjacent HU ranges to compute the mass density (ρ):
for example (for 700 ≤ HU < 800):
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Element Mass Fractions :
Each material’s composition is defined by mass fractions (f.i) of elements(e.g., H: 0.061, C: 0.287). Element-specific mass densities are calculated as ρi (g/cm3) = f.i * ρ (g/cm3).
2. Electron Density Calculation
For each voxel, the electron density is computed using:
I would like to confirm whether this methodology is aligned with the way FLUKA internally interprets CT-based geometry when using ‘material.ini’ and ‘body.mat’.
Thank you for your time and support!