NTracks dans TauJet et Jet

[Xavier Rouby]

Hello,
On Mon, 14 Jun 2010 17:19:43 +0200, Chris Boddy <c.boddy1@…> wrote:

Great! we have been waiting for your updated Delphes package.

One point though; I have installed and ran it on some files. I notice that almost every jet and taujet candidate seems to have Ntracks = 0, whereas Delphes_V_1.8 had a realistic distribution. Is there any reason to expect this now?

Thanks,
Chris

[Pavel Demin]

For the moment, in Delphes 3, the number of tracks is not stored in the output ROOT file.

The reason is that it is not clear how to define this value: we could count either tracks in a cone of given (by whom?) radius or tracks that are really used to reconstruct jet (jet's constituents).

As the output ROOT file contains all necessary information, this value can be easily calculated in the analysis ROOT macro. For example, root2lhco.cpp contains the following code:

    TIterator *fItTrack = fBranchTrack->MakeIterator();
    ...
    Int_t counter = 0;
    fItTrack->Reset();
    while((track = static_cast<Track*>(fItTrack->Next())))
    {
      if(element->P4().DeltaR(track->P4()) < 0.5) ++counter;
    }