1. 1 Techincolor and Heavy Top/B search Tulika Bose Meenakshi Narain (Brown University) Work done in the context of Les Houches 2007

2. 2 Exotic top partners Some BSM theories predict the existence of: heavy top quark partner heavy bottom Model suggested by Contino and Servant : arXiv:0801.1679 (2008) “Discovering the top partners at the LHC using same-sign dilepton final states” Perform a sensitivity study using CMS fast simulation samples: Figures from slides of a presentation by R. Contino (TH-CERN) (Bose, Narain)

3. 3 Exotic top partners Some BSM theories predict the existence of: heavy top quark partner heavy bottom Figures from slides of a presentation by R. Contino (TH-CERN) Look for same-sign di-lepton states reduces the ttbar background Look for a resonant tW invariant mass peak (T 5/3 )

4. 4 Hunting for a heavy T Signal & background samples generated using Madgraph Pythia showering/hadronisation Quark/Jet matching a la MLM BKG Table from Contino and Servant : arXiv:0801.1679 (2008) Signal

5. 5 Hunting for a heavy T Samples processed via Fastsim CMSSW_1_6_8 Iterative 0.5 Cone Jets Correct Jets (jet_corrections_16X) Bkg combined according to expected cross sections

6. 6 Hunting for a heavy T.. 2 same sign isolated leptons –(electrons or muons) with |  | < 2.4 pT > 50 GeV for the leading lepton pT > 25 GeV for the second leading lepton. Missing transverse energy > 20 GeV.

7. 7 Hunting for a heavy T.. 1) At least 5 jets with pT > 30 GeV and |  | < 5.0. pT > 80 GeV for the second leading jet. pT > 100 GeV for the leading jet

8. 8 CMS Discovery Potential Background is under control for such a signal Triggers: Single lepton, di-lepton (including e+mu and same-sign triggers); Lepton + jets Estimate the following for T 5/3 + B: 5  observation: ~ 240 pb -1 with sys errors: 30% for signal and 50% for bkg with no sys errors: ~ 230 pb-1 # of Signal events 25.8; bkg events: 0.96

9. 9 Reconstructing the heavy T Reconstructing the first W (from top decay) (eff: 0.84) –Take the two jets with invariant mass consistent within 20 GeV of W boson. –If a btagged jet is found close to the second leading lepton, the jet is removed from consideration. –Require  Rjet 50 GeV. Reconstructing the second W (from heavy exotic top) –Remove jets associated with first W. –Take the two jets with invariant mass consistent within 25 GeV of W boson. –Require  Rjet 30 GeV. W from top decayW from heavy top

10. 10 Reconstructing the heavy T Reconstructing the heavy Top (from top decay) –Discard the four jets that were assigned to the two W bosons –Combine the btagged jet with one of the two W bosons to get the top quark Take the one that is closest to top quark mass (within 40 GeV) –The top quark candidate is combined with the other W boson to yield the heavy top partner - T(-5/3) top quark from heavy T Recons. heavy Top and B

11. 11 Reconstructing the heavy T With Mass reconstruction: Estimate the following for T 5/3 + B: 3  evidence: ~ 250 pb -1 5  observation: ~ 650 pb -1 10 fb -1 efficiencies for reconstructing 2 W candidates and one top candidate.

12. 12 Technicolor aT;aT; Extend TCSM2 to include a T (Bose)

13. 13 High mass di-boson resonance: Technicolor signal:  TC  W Z (clean with leptonic W & Z decays) Technicolor (Multiple lepton signature) GeV fb

14. 14 Selection criteria

15. 15 Technicolor (Multiple lepton signature) Triggers: Single, di-leptons Selection criteria: 3 isolated leptons (electron or muon) –Electron p T > 15 GeV, |  | < 2.5 –Muon p T > 15 GeV, |  | < 2.5 Missing transverse energy –E T > 40 GeV Two oppositely charged leptons with Z invariant mass Leptonic H T (scalar sum of transverse momenta of leptons) > 150 GeV Z p T > 65 GeV; W p T > 65 GeV (computed using lepton and missing Et) Event Selection Efficiencies: Mass (GeV)Efficiency 3000.20 4000.29 5000.34

16. 16 CMS Discovery Potential 5  observation 10 fb -1 Promising LHC discovery channel with clean signature! Mass (GeV)Num of Signal eventsNumber of Bkg events 30036.115.1 40036.216.1 50033.711.9

17. 17  T, a T Mass Reconstruction The two mass peaks for  T and a T are not separated due to the Missing E T resolution. (ATLAS study sees a separation). Generator Level After Reconstruction Rho T aTaT

18. 18 Conclusion CMS discovery potential for T(-5/3) and Technicolor decays to multileptons have been evaluated. Work done via fastsim Move to using full simulation and standard object IDs and corrections.