310 likes | 431 Views
NMSSM Higgs Search. Search for neutral NMSSM Higgs Studies at 10 TeV, and with the 2010 data @ 7 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. N MSSM.
E N D
HEP Conference NMSSM Higgs Search Search for neutral NMSSM Higgs Studies at 10 TeV, and with the 2010 data @ 7 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 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 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 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 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 Channels investigated and associated background • Background processes: • ZZjj and WZjj production: • TTbar production: t Wb • Zbbbar and Wbbbar production:
HEP Conference Cross Section @ 10 TeV • Vector Boson Fusion 93.8% 17.8% 65.4% 92.6% M. Spirq, Fortsch Phys. 46 (1998) 203, http://people.web.psi.ch/spira/proglist.html For L = 200 pb-1, NLO = 6.5 and NNLO = 6.3
HEP Conference Cross Section
HEP Conference μ-τ Skim • Muon • Global Muons, Pt > 6 GeV, abs(η) <2.5 • Tau • caloRecoTauDiscrimainationByLeadingTrackPtCut: 0.5 • Calo Tau: Leading Track Pt > 5GeV within ΔRmatching = 0.1 • Muon-Tau • DiTauAntiOverlapSelector ΔR = 0.01
HEP Conference Event Selection
HEP Conference Event Selection Normalized
HEP Conference Cuts
HEP Conference Cuts
HEP Conference Muon Identification Muon Reconstruction PT Resolution / • Muons: “global muons”
HEP Conference Tau Identification Tau Reconstruction PT Resolution / • Taus: particle-flow techniques “PFTau”
HEP Conference Missing Transverse Energy (MET) The pfMET algorithm PMET Resolution MET Resolution
HEP Conference Total number of Taus and muons
HEP Conference Mass Reconstruction had μ vμ vτ τ PTmiss a1 vμ h1 μ τ a1 vτ had • The mass and PT of the h are sufficiently large to give a considerable boost to its decay products. The direction of the a1, 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 a1 are neglected compared to the typical mass of h1.
HEP Conference Collinear Approximation
HEP Conference x1 andx2 before Muon-Tau Selection
HEP Conference ΔR and mass distributions between muon-jet
HEP Conference ΔR and mass distributions between a-a
HEP Conference Invariant mass of a and h using Collinear Approximation
HEP Conference Data and Monte Carlo Samples at 7 TeV • Data Run-range • /Mu/Run2010A-Nov4ReReco_v1/RECO 136033-144114 • /Mu/Run2010B-Nov4ReReco_v1/RECO 146428-149442 • Trigger Path • HLT_Mu9, HLT_IsoMu9, HLT_Mu11, HLT_Mu15, HLT_IsoMu13 • HLT_IsoMu9_PFTau15, HLT_IsoMu11_PFTau15 Monte Carlo
HEP Conference Efficiency Selection
HEP Conference mass distributions
HEP Conference ΔR and mass distributions between muon-jet
HEP Conference ΔR and mass distributions between a-a
HEP Conference Conclusion • 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 Thanks • We acknowledge support from Research Promotion Foundation(IPE) cyprus