HEP Conference 1 NMSSM Higgs Search Search for neutral NMSSM Higgs Studies at 10 TeV, and with the TeV Jehad Mousa University of Cyprus ANNUAL MEETING OF THE HELLENIC SOCIETY FOR THE STUDY OF HIGH ENERGY PHYSICS April 14-16, 2011, University of Patras, Greece

HEP Conference 2 NMSSM  The Next-to-Minimal Supersymmetric Standard Model (NMSSM) extends the MSSM by the introduction of a singlet superfield ( )  The NMSSM naturally solves the μ-problem of the MSSM.  The Higgs sector of the NMSSM contains (three CP-even bosons h1, h2, h3 and two CP-odd higgs bosons α1, α2) and two charged higgs bosons (h  ).

HEP Conference 3 The benchmark points The lightest pseudoscalar higgs boson is rather light, and the lightest CP-even higgs has enough phase space for the decay into two pseudoscalar higgs boson, to be kinematically accessible. The BR for the decay is very large and this new channel is the dominant one. Concerning the further decay of the lightest pseudoscalars, there are two possibilities: – Either and the boson decays into a pair of b quarks or a pair of tau leptons, leading to and final states, – or and the dominant decay mode of the boson is into a pair of tau leptons, leading to final state.

HEP Conference 4 Channels investigated and associated background The signal process: A Vector Boson Fusion: Two different types of scenarios are considered, depending on  Scenarios with are disfavored when LEP data for Z2b and Z4b final states are taken into account.  On the contrary, scenarios with are favored by the same data and can even account for 2σ excess observed in the Z2b final state in the vicinity.

HEP Conference 5 Channels investigated and associated background higgs-strahlung: The decay, with produced in higgs-strahlung with leptonic decays of the W or Z boson, which can give a very clean and almost background free signal, is one of the most promising higgs decay channels according to the last investigation of phenomenological scenarios

HEP Conference 6 Channels investigated and associated background Background processes:  ZZjj and WZjj production:  TTbar production: t  Wb  Zbbbar and Wbbbar production:

HEP Conference 7 Cross 10 TeV Vector Boson Fusion M h (GeV)Typical cross –section for VBF (fb) LONLO For L = 200 pb -1, N LO = 6.5 and N NLO = 6.3 M. Spirq, Fortsch Phys. 46 (1998) 203, % 17.8%65.4%93.8%

HEP Conference 8 Cross Section

HEP Conference 9 μ-τ Skim Muon Global Muons, P t > 6 GeV, abs(η) <2.5 Tau caloRecoTauDiscrimainationByLeadingTrackPtCut: 0.5 Calo Tau: Leading Track P t > 5GeV within ΔR matching = 0.1 Muon-Tau DiTauAntiOverlapSelector ΔR = 0.01 SampleGen Events σ (fb)MC Filter Efficiency Skim Efficiency ZZ  4l Zbb  4l

HEP Conference 10 Event Selection Vertex Selection  p(chi2Vertex) > 0.01  -25 < zVertex < +25 cm Muon Selection  global Muon  -2.1 < eta(Muon) < +2.1  Pt(Muon) > 8 GeV  Muon Track iso.  Muon ECAL iso.  Muon pi-Veto  Muon Track IP Tau Selection  Tau not overlapping w. Muon  -2.1 < eta(Tau) < +2.1  Pt(Tau) > 10 GeV  Tau lead. Track find.  Tau lead. Track Pt  Tau 1||3-Prong  Charge(Tau) = +/-1  Tau mu-Veto  Tau Electron-Veto

HEP Conference 11 Event Selection Muon-Tau Selection  Charge(Muon+Tau) = 0  Acoplanarity(Muon+Tau)  M T (Muon-MET) < 50 GeV  dR(Muon-Tau) < 0.5 a-a Selection  dR(a-a) > 0.3  Acoplanarity (a+a)  M T (a-MET) < 50 GeV Normalized

HEP Conference 12Cuts CutHtoaaTTbarFourlZZFourlllbb gen. Phase-Space Vertex p(chi2Vertex) > < zVertex < +25 cm global Muon -2.1 < eta(Muon) < +2.1 Pt(Muon) > 8 GeV Tau not overlapping w. Muon -2.1 < eta(Tau) < +2.1 Pt(Tau) > 10 GeV Muon Track iso. Muon ECAL iso. Muon pi-Veto Muon Track IP

HEP Conference 13 Tau lead. Track find. Tau lead. Track Pt Tau 1||3-Prong Charge(Tau) = +/-1 Tau mu-Veto Tau Electron-Veto dR(Muon-Tau) < 0.5 Charge(Muon+Tau) = 0 Acoplanarity(Muon+Tau) M_{T}(Muon-MET) < 50 GeV dR(a-a) > 0.3 Acoplanarity(a+a) M_{T}(Muon-MET) < 50 GeV Cuts

HEP Conference 14 Muon Identification Muon Reconstruction  Muons: “global muons” P T Resolution /

HEP Conference 15 Tau Identification Tau Reconstruction  Taus: particle-flow techniques “PFTau” P T Resolution /

HEP Conference 16 Missing Transverse Energy (MET) The pfMET algorithm P MET Resolution  MET Resolution

HEP Conference 17 Total number of Taus and muons

HEP Conference 18 Mass Reconstruction P Tmiss vμvμ μ a1a1 τ vτvτ μ had vμvμ a1a1 h1h1 τ vτvτ  The mass and P T of the h are sufficiently large to give a considerable boost to its decay products. The direction of the a 1, of the two τ, of the two μ, of the two hadron and of the three neutrinos are then nearly parallel.  The missing transverse momentum originates exclusively from the neutrinos from the decay chain of the h.  The masses of the final state leptons and the a 1 are neglected compared to the typical mass of h 1.

HEP Conference 19 Collinear Approximation

HEP Conference 20 x 1 and x 2 before Muon-Tau Selection

HEP Conference 21 ΔR and mass distributions between muon-  jet

HEP Conference 22 ΔR and mass distributions between a-a

HEP Conference 23 Invariant mass of a and h using Collinear Approximation

HEP Conference 24 Data and Monte Carlo Samples at 7 TeV Data Run-range /Mu/Run2010A-Nov4ReReco_v1/RECO /Mu/Run2010B-Nov4ReReco_v1/RECO Trigger Path HLT_Mu9, HLT_IsoMu9, HLT_Mu11, HLT_Mu15, HLT_IsoMu13 HLT_IsoMu9_PFTau15, HLT_IsoMu11_PFTau15 SampleGen Events σ (fb) (NLO) MC Filter Efficiency Skim Efficiency Monte Carlo

HEP Conference 25

HEP Conference 26 Efficiency Selection

HEP Conference 27 mass distributions

HEP Conference 28 ΔR and mass distributions between muon-  jet

HEP Conference 29 ΔR and mass distributions between a-a

HEP Conference 30Conclusion  Results of a search for NMSSM neutral Higgs to four taus productions in the channel 2mu + 2tau have been presented.  No evidence fo a NMSSM neutral Higgs signal in the proton-proton collision data collected by the CMS experiment in 2010 is found.

HEP Conference 31Thanks We acknowledge support from Research Promotion Foundation (IPE) cyprus