Declaration: TParticles.AuxPar [PartIx: integer]: double;
The array property AuxPar contains an auxiliary double-precision value for each particle. You can freely use it for your own purposes, Epina ImageLab does not process it in any way. The parameter PartIx is the particle index (range 1..NParticles).

Hint: In order to access the particles currently loaded in the particle editor you can use the pre-declared global variable PEData.