wiki:Korea2017-04-CMS-SUS-16-041

The first MadAnalysis 5 workshop on LHC recasting @ Korea

Analysis 4: CMS-SUS-16-041

Students Byeonghak Ko (Analysis Webpage Editor), Tae Gyu Ro, Jubin Park, Kyeongpil Lee
Supervisor(s) Guillaume Chalons

1. Analysis summary

Search for new physics n events with at least 3 electrons or muons and jets. Results are based on 35.9 fb-1 Luminosity at 13 TeV collected by CMS. Events are classified according to the number of b jets, missing transverse momentum, hadronic transverse energy, and the invariant mass of opposite-charge, same-flavor dilepton pairs. Exclusion limits are set for 4 different simplified SUSY models with gluino or 3rd gen. squarks pair production.

2. Analysis global information

3. Selection description

3.1 Trigger selection

Trigger selections target di- and multilepton events.

One trigger set requires:

  • The two leptons required to meet the loose isolation criteria
  • Leading lepton has pT > 23 GeV
  • Sub-leading lepton has pT > 8 (12) GeV in the case of muons (electrons)

Second set of triggers requires:

  • pT > 8 GeV for both leptons
  • HT (hadronic activity) > 300 GeV

PS: This part cannot usually be described by the fast-simulation of detector.

3.2 Object definition

  • Jets:
    • clustered with anti-kt algorithm with Delta R = 0.4
    • pT > 30 GeV
    • | eta | < 2.4
  • B-jets:
    • b-tag efficiency 70%
    • misidentification probability of 10% and 1% is for c- and light-flavor jets, respectively.
    • pT > 25 GeV & | eta | < 2.4
  • Hadronic activity
    • HT = Sum pt of the jets where all jets have pt > 30 GeV
  • Muon: | eta | < 2.4
  • Electrons: | eta | < 2.5

Explained here how the objects are defined.

3.3 Cut-flow chart

3.4 Definition of exotic observables

Like SUSY transverse observable. Notice that classical MT2 & MT2W are encoded within the MadAnalysis framework.

4. Detector simulation

Can we use the last release of the Delphes package with the CMS/ATLAS MA5tune-card? or do need to improve the simulation?

5. Validation material

Contact with CMS established. Waiting for the validation material requested

5.1 Monte-Carlo samples

  • LO/NLO? LO
  • Model used: gluino -> t t +LSP, gluino -> q qbar chi_2/chi_1±
  • MC generator program (name + version): PYTHIA 8.???
  • Shower program (name + version): PYTHIA 8.???
  • Tune of Pythia: ???
  • PDF set:
  • ME/PS merging????

5.2 Reference plots / cut-flows

  • List of validation material
  • Two outflows for gluino pair production

6. Validation results

7. Reinterpretation (optional)

8. Questions / issues

9. Analysis People Contacts

  • Guillaume Chalons: [mail:guillaume.chalons@th.u-psud.fr]
  • Byeonghak Ko: [mail:quark2930@hotmail.com]
  • Tae Gyu Ro: [mail:shxorb234@gmail.com]
  • Jubin Park: [mail:honolov77@gmail.com ]
  • Kyeongpil Lee: [mail: kplee@cern.ch]
Last modified 3 years ago Last modified on 08/23/17 08:54:27

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