Status of NMSSM H(125) → µµττ Search with 2016 Dataset ıguez 1 , T. Lenz 1 , S. Consuegra Rodr´ A. Raspereza 1 and Danyer P´ A. Kalogeropoulos 2 , an 1 erez Ad´ 1 DESY-Hamburg 2 Princeton University Higgs Exo Meeting, 2018/03/05 S. Consuegra Rodr´ ıguez Status of NMSSM H(125) → µµττ March 5, 2018 1 / 16
Outline Short reminder on Signal Signature, Analysis Strategy and Background Model News Optimization studies: MET-based, ∆Φ( µ − trk Atautaucandidate, MET) and Invari- ant mass of Atautaucandidate Signal Interpolation Signal Fitting Summary S. Consuegra Rodr´ ıguez Status of NMSSM H(125) → µµττ March 5, 2018 2 / 16
Short reminder on Signal Signature and Analysis Strategy gg → H(125) → aa → ( µ µ )( τ µ τ 1 − prong ) probe low m a region 2 m τ < m a < 2 m b Final state with three muons, one pair has same sign In the decay of one of the a, one of the τ leptons is identified via its muon decay The other τ lepton is required to decay into one charged particle and one or more neutral particles We identify these decay by the presence of one reconstructed track with charge sign opposite to that of the closest muon. Neutral particles are not considered in the event selection The decay of the other a, is identified via its double muon decay S. Consuegra Rodr´ ıguez Status of NMSSM H(125) → µµττ March 5, 2018 3 / 16
Short reminder on Background Model The Background Model is constructed and validated in side band region a → µµ candidate is required to be isolated No additional requirements are imposed to a → ττ candidate muon (no isolation requirement applied) The full background model consists of SM resonances [Υ(1 s ) , Υ(2 s ) , Υ(3 s )] and a non resonant continuum background (low mass DY background, t t and QCD) S. Consuegra Rodr´ ıguez Status of NMSSM H(125) → µµττ March 5, 2018 4 / 16
News Track isolation efficiency was added Monte Carlo samples for mass points: (6,8,10,12 and 14) GeV are still missing, but we have signal distributions (5,7,9,11,13 and 15) GeV parameterized using double sided crystal ball functions (composed by 2 crystal balls CB1 and CB2). Each of the crystal balls depends on 4 parameters: mass, sigma, alpha and n. The crystal balls are taken with the same values of mass, alpha and n, but different sigma Horizontal interpolation between 2 templates of the not missing mass points was performed for the missing mass points (6,8,10,12 and 14) GeV Validation of the interpolation procedure already performed. Actual and interpolated pdf are compatible within MC statistical uncertainties New datacards for the interpolated mass points are ready With workspaces and datacards the new mass points are now added to the analysis, e.g. expected sensitivity for 2016 dataset S. Consuegra Rodr´ ıguez Status of NMSSM H(125) → µµττ March 5, 2018 5 / 16
Optimization Studies Tasks: Look for improvements in sensitivity applying optimization cuts on: - ∆Φ( µ − trk Atautaucandidate, MET)=[ ≤ 1 , ≤ 2 , > 0] (Atautaucandidate is the third muon associated to one of the same sign muons + close by track within predefined isolation cone ∆ R Iso ) - MET [ ≤ 85 , ≤ 120 , > 0] Separate the phase space of the invariant mass distribution of a → ττ candidate in 3 channels [0-2, 2-5, 5-20]: - This required to produce new workspaces and datacards for each of the mass points [6 (mass points) x 3 (channels)= 18 datacards] - After having separated channels each with it’s own datacard, a combined datacard was produced per mass point Possible improvement in sensitivity with the combination of the 3 datacards per mass point was explored S. Consuegra Rodr´ ıguez Status of NMSSM H(125) → µµττ March 5, 2018 6 / 16
∆Φ optimization study ∆Φ( µ − trk Atautaucandidate, MET)=[ ≤ 1 , ≤ 2 , > 0] S. Consuegra Rodr´ ıguez Status of NMSSM H(125) → µµττ March 5, 2018 7 / 16
MET optimization study MET [ ≤ 85 , ≤ 120 , > 0] S. Consuegra Rodr´ ıguez Status of NMSSM H(125) → µµττ March 5, 2018 8 / 16
Invariant mass optimization study Invariant mass of Atautaucandidate=[0, 2, 5, > 5] S. Consuegra Rodr´ ıguez Status of NMSSM H(125) → µµττ March 5, 2018 9 / 16
Results of Optimization studies The proposed cuts on ∆Φ( µ − trk Atautaucandidate, MET)=[ ≤ 1 , ≤ 2] did not result in improvement of sensitivity since distribution of ∆Φ for SR events on data and signal is very similar. A slight improvement on sensitivity is observed when applying the cut on MET ≤ 120. Sensitivity considering all mass spectrum of a → ττ candidate [0,20] is improved when using the combination of the three channels for each mass point, as expected. This was assessed only for the available MC samples, not for the interpolated mass points. The invariant mass distribution of the a → µµ candidate for mass points 6,8,10,12 and 14 GeV was obtained, as explained above, by horizontal interpolation. As a consequence of this, we don’t have information of the accompanying a → ττ candidate, and, phase space of a → ττ invariant mass can not be divided in 3 different channels for the interpolated mass points. S. Consuegra Rodr´ ıguez Status of NMSSM H(125) → µµττ March 5, 2018 10 / 16
Signal Interpolation S. Consuegra Rodr´ ıguez Status of NMSSM H(125) → µµττ March 5, 2018 11 / 16
Signal fitting S. Consuegra Rodr´ ıguez Status of NMSSM H(125) → µµττ March 5, 2018 12 / 16
Other plots Background: Asimov data set with shape from sideband, normalized to data yield in signal region Signal normalization: σ ( gg → H (125)) = σ SM (13 TeV ) ≡ 43 . 9 pb B ( H (125) → aa ) · B 2 ( a → ττ ) = 20% Expected signal and background Signal Model pdfs distribution in signal region S. Consuegra Rodr´ ıguez Status of NMSSM H(125) → µµττ March 5, 2018 13 / 16
Expected Sensitivity for 2016 dataset With the interpolated mass points 6,8,10,12 and 14 GeV, evaluated in terms of expected 95% CL limits on: B ( H (125)) → aa . Mass point -2s -1s exp +1s +2s m a 1 =5 GeV 0.014 0.021 0.034 0.056 0.090 m a 1 =6 GeV 0.020 0.029 0.046 0.078 0.127 m a 1 =7 GeV 0.020 0.030 0.047 0.079 0.129 m a 1 =8 GeV 0.025 0.038 0.061 0.102 0.165 m a 1 =9 GeV 0.029 0.043 0.069 0.116 0.187 m a 1 =10 GeV 0.035 0.052 0.083 0.137 0.220 m a 1 =11 GeV 0.037 0.055 0.088 0.150 0.245 m a 1 =12 GeV 0.041 0.061 0.101 0.173 0.285 m a 1 =13 GeV 0.049 0.073 0.121 0.206 0.343 m a 1 =14 GeV 0.055 0.082 0.136 0.233 0.387 m a 1 =15 GeV 0.060 0.091 0.150 0.259 0.428 S. Consuegra Rodr´ ıguez Status of NMSSM H(125) → µµττ March 5, 2018 14 / 16
Summary At the moment, the only available samples are gg − > H with ma = 5-15, with 2 GeV step. The following MC samples are needed (highest priority samples): gg − > H at the pseudoscalar masses with even values (4,6,8,10,12 and 14 GeV) VBF with ma = 4-15 GeV with 1 GeV step Also desirable: VH and ttH samples with ma = 4-15 GeV with 1 GeV step Mass point just above a − > tautau decay threshold, ma = 3.5 GeV S. Consuegra Rodr´ ıguez Status of NMSSM H(125) → µµττ March 5, 2018 15 / 16
Backup We can also determine the evolution of the parameters of the signal pdf as a function of the pseudoscalar mass, apply a fit to each of the parameters, and interpolate to obtain the corresponding values for the mass points not covered by simulation Parameters of the signal model crystal ball pdfs: S. Consuegra Rodr´ ıguez Status of NMSSM H(125) → µµττ March 5, 2018 16 / 16
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