The ninth column of lhco ouputs

[Tathagata Ghosh]

Hi Delphes experts,

I am trying to do an analysis where I need to deal with soft leptons. So, I was following the isolation criteria used by SUS-16-048-pas, a CMS analysis on a compressed-SUSY spectrum. For that, I need to apply an upper cut on Iso_abs < 5 GeV for effective soft lepton isolation. Iso_abs is the sum of pT of all tracks within a cone of DeltaR < 0.3 around the lepton candidate, excluding the lepton. I could not apply the above cut at the Delphes_card level as Delphes does not have any control parameter in its card for this. Besides, while studying the "../Delphes/converters/root2lhco.cpp" file I noticed that although I set DeltaRMax to be 0.3 for leptons in the Delphes_card, for calculating Iso_abs (which is printed on the ninth column of the lhco output for muons), Delphes is still using a cone radius of 0.3. So, I edited the above value in the root2lhco.cpp file. Also, I edited the file to print the Iso_abs for both muon and electron in the tenth column by including "fDblParam[7] = Float_t(sumPT);". I've attached the edited root2lhco_edit.cpp file with this message.

However, while comparing the results, it seems Iso_abs values printed by Delphes on the ninth and tenth columns of lhco files are very close to the corresponding muon pT. So, I am wondering whether Delphes is printing the sum of pT of all tracks and not subtracting the muon pT. I want to point out that Delphes converter was already using the variable sumPT on the ninth column for muons. I only edited the file to reprint it in the tenth column and repeated the same for the electron. I've attached a lhco file with the above edit for your comparison.

I'll be highly obliged if you kindly shed some light on this matter and point out if I'm making any mistake or not.

Thanks in advance,
Tathagata

[Pavel Demin]

I could not apply the above cut at the Delphes_card level as Delphes does not have any control parameter in its card for this.

The recommended way is to apply the analysis cuts in the the code analyzing the .root files produced by Delphes.

So, I am wondering whether Delphes is printing the sum of pT of all tracks and not subtracting the muon pT.

Yes, it seems to be the case.