[Rivet] ZFinder problem report

[Yatsenko, Elena]

Hello,

During implementation of the ATLAS ZpT analysis with Rivet v1.6.0 we've found a problem in ZFinder class with clusterPhotons flag.
If clusterPhotons =«false» dR cut is not effective for the 4 momentum of the Z boson .
So in our case

ZFinder zfinder_dressed_el(-2.4, 2.4, 20, ELECTRON, 66.0*GeV, 116.0*GeV, 0.1, false, false);
 and
ZFinder zfinder_bare_el(-2.4, 2.4, 20, ELECTRON, 66.0*GeV, 116.0*GeV, 0.0, false, false);

will give the same results. While the class documentation suggest that clusterPhotons is meant to only correct the 4 vectors of the decay lepton.

Could you please look at this and find out the source of the problem?

Regards,
Elena Yatsenko