Table 1 Database materials defining the nodes of the CT ramp with corresponding mass stopping power ratio (mSPR) and empirical parameter for the continuous slowing down approximation aCSDA
From: Adaptive step size algorithm to increase efficiency of proton macro Monte Carlo dose calculation
Material | HU value | Density [g/cm 3] | mSPR | aCSDA [cm/MeV 2] |
|---|---|---|---|---|
Air | -1000 | 0.00125 | 0.88 | 0.765 |
Lung | -610 | 0.384 | 0.99 | 0.002640 |
Adipose tissue | -77 | 0.95 | 1.03 | 0.001019 |
Muscle | 40 | 1.05 | 1.00 | 0.000963 |
Spongiosa | 102 | 1.1 | 0.99 | 0.000920 |
Cortical bone | 1524 | 1.92 | 0.89 | 0.000608 |
Teeth | 3055 | 2.75 | 0.86 | 0.000445 |