 WW / ZZ separation Some clarification on how the main background is rejected how the detector performances are involved J.C. BRIENT

Starting point Mass J3 J4 (GeV) Mass J1 J2 (GeV) ∆EJ = 0.60 EJ Simulation with Simulation with Mass J3 J4 (GeV) Starting point Mass J1 J2 (GeV) This presentation Add background e±  W∓ Effect when using the VDET btag Quantify the results with S/N ratio for different searches J.C. BRIENT

ZZ, WW, eWZ,  Select 4 jets ∆EJ = 0.30 EJ Simulation with 4 12 45 Cross sections (fb) ZZ, WW, eWZ, Mass J3J4 (GeV) Mass J1J2 (GeV) ∆EJ = 0.30 EJ Simulation with J.C. BRIENT

ZZ, WW, eWZ, With all decays to jets. Processes 1 2 3 ZZ, WW, eWZ, With all decays to jets. In the fiducial volume of the detector, an isolated electron with high energy is a good tagging for process (3) ALL processes Process (3) Electron energy (GeV) J.C. BRIENT

Reject if The low angle coverage for electron is ESSENTIAL Electron Energy >100GeV (50 at low angle) MM2<500 and Electron Energy >5GeV MM2<250 and Electron Energy >2.5GeV The low angle coverage for electron is ESSENTIAL process e+ e− → e±  W∓ Z (blue) almost disappears, while leaving processes (1) and (2) unchanged Mass J3 J4 (GeV) Mass J1 J2 (GeV) J.C. BRIENT

≈ 12.2 Select ≥ 2 b-jets Mass J3 J4 (GeV) Mass J1 J2 (GeV) S(ZZ) B(WZ,WW) ≈ 12.2 Mass J3 J4 (GeV) Mass J1 J2 (GeV) J.C. BRIENT

≈ 100 ≈ 18.6 ≈ 2.4 Select < 2 b-jets After cut Before di-jet mass cut S(WW,ZZ) B(WZ) ≈ 100 After cut WW region: Contains 89 % of the WW and S(WW) B(ZZ, WZ) ≈ 18.6 ZZ region: Contains 71 % of the ZZ S(ZZ) B(WW, WZ) ≈ 2.4 J.C. BRIENT

e±  W∓ background can be removed easily Other relevant backgrounds seem easier to remove (guess) i.e. WW, Z() could be rejected with missing energy and mass e±  W∓ background can be removed easily (with a good electron id. at low angle ) the main problem is still the WW/ZZ separation For ZZ rejection, a good VDET btag can help the PFLOW performance is still the key point for the analysis J.C. BRIENT