Truth-matching reco jets to associated gen-level particles

In the 2015 miniaod formatted CMS open data collections, is there a standard branch or property that can be used to truth-match reco::GenParticle items to their corresponding pat::Jet?

If not, is the practice of matching deltaR the standard approach? Finally, if using deltaR is the standard approach then, is there a typical threshold used for considering two items to be a match?

Hi Eric,

Indeed, Delta-R is the typical method, and we use DR < 0.4 for “AK4” jets and < 0.8 for “AK8” jets.

You can ask a pat::Jet for its associated generated jet object:

And then from the generated jet you have more direct access to the generated particles:

(e.g. through “getConstituents”)