How to : Calibrate DOSXYZnrc

Calibrate DOSXYZnrc from dose per particle to dose per MU

One needs to run a calibration simulation that mimics the linac calibration. The calibration point is set at the location of 1 cGy = 1 MU. Determine the dose per particle value at that location. This value is your DOSXYZnrc calibration value. For a generic 6MV beam you might have a value around 1.34e-14 at the location of 1 cGy = 1 MU. For most users they will run a water simulation with a field size of 10x10, SSD of 100 cm and reference the dose at Dmax.

The DOSXYZnrc calibration value should be copied to Configurations > Beam models > Treatment Head Calculation settings. From this point on, whenever this beam energy is selected, this value will be assigned to your DOSXYZnrc "Calibration dose" value for the associated beam.

Dose to water can be left as 1. This is used if one wants to convert dose to water from your dose to media calculation using a fixed mass-energy absorption ratio.

The 3ddose file is imported and normalize using "Calibration dose", MUs, and beam weight to determine dose in cGy.