How are α and β values in carbon_Generic.mat calculated in matRad? Any references or code available?

[yangshiyan]

Dear matRad experts,

I am currently building my own carbon ion machine model in matRad. I noticed that the official carbon ion machine file (carbon_Generic.mat) contains two parameters, α and β. These values seem to depend on the carbon ion energy and depth, but I am not sure how they are actually calculated.

Could you please clarify:

What is the method used to calculate the α and β values in carbon_Generic.mat?

Are they obtained through a specific biophysical model (e.g., LEM IV) based on photon reference parameters and LET distributions?

Is there any detailed documentation, publication, or example code available that explains how to generate or modify these α/β tables for carbon ion base data?

Any guidance or references would be greatly appreciated.