No MC matching in DaVinci using persistreco objects to build particles

Bug found when trying to use the MCTruthAndBkgCat tool with a candidate built within DaVinci using a particle combiner

  psi = ParticleCombiner(
    [muons_with_pid,muons_with_pid],
    DecayDescriptor="J/psi(1S) -> mu+ mu-",
    name="Commissioning_Psi",
    CombinationCut=F.require_all(in_range(2900, F.MASS, 150000)),
    CompositeCut=F.require_all(in_range(2900, F.MASS, 150000),F.CHI2DOF < 25,
    ),
  )

  MCTRUTH = MCTruthAndBkgCat(psi, name="MCTruthAndBkgCat")

Code runs but the truth variable are left empty.

Edited Dec 05, 2023 by Sevda Esen