How to get mother PdgID of generator level particle in Delphes

[snandan]

Hi,

I am running delphes using hepmc input. I don't understand the meaning of M1, M2, D1, D2. Does M1 or M2 mean the mother's pdgid of a particle? I want to match some final particle with generator level particle for which I need generator level information. I'll be grateful if some one explains how Delphes read the hepmc input.

Thanks,
saswati

[Michele Selvaggi]

It is the index of appearance in the Particle collection.
For example, if you want to access the D1 of a given particle "gen" , you can do:

daughter = branchParticle.At(gen->D1)