Extended Scalar Searches at ATLAS & CMS Allison McCarn - PowerPoint PPT Presentation

Extended Scalar Searches at ATLAS & CMS Allison McCarn (University of Michigan) On behalf of the CMS and ATLAS Collaborations ! Rencontres de Moriond EW 2016 1

Beyond the Standard Model BSM physics was not observed in run-1, but there are still many possible models to be investigated in run-2. Higgs Triplet: Two-Higgs Double Models (2HDM): An additional scalar The observed Higgs triplet results in charged, Additional Higgs Doublet doubly-charged, and boson at 125 GeV could gives rise to 5 Higgs neutral bosons. bosons (H,h,A,H±) be only the beginning. ! A few examples out of Minimal Supersymmetric many… 2HDM+S: Standard Model: Two Higgs Doublets Higgs Sector is Type-II and an additional 2HDM. Current complex singlet (e.g. common benchmark is Electroweak Singlet (EWS): NMSSM) hMSSM. Additional singlet, resulting in 2 CP-even bosons. 2

Run-1 Results/Run-2 Prospects Phys. Rev. D 92, 092004 (2015) Many searches were performed in run-1, • with 7 and 8 TeV centre-of-mass energy at the LHC, but physics beyond the Standard Model has not yet been observed. ! An example of where we stand and hopes • for the future of the LHC can be seen in the hMSSM overlay and prospect plots. – Much parameter space is excluded, but there is still room for high mass Higgs to be found! Djouadi et al: hMSSM (arXiv:1502.05653) In 2015, ATLAS collected 3.2 fb -1 and CMS collected 2.8 fb -1 of data at 13 TeV! ! This is already enough in many cases to exceed run-1 sensitivity! 3

Beyond the Standard Model Searches in this Presentation Many searches for run-2, as well as a few final searches for run-1, from ATLAS, CMS, and both. Charged Higgs Di-Higgs H ± à τν (13 TeV) H à hh à bbγγ (13 TeV) H ± à tb (8 TeV) H à hh à bbττ (8/13 TeV) φ ±± φ ±± à lllν/4l (8 TeV) Dibosons Neutral Higgs H à ZZ à 4l (13 TeV) H à ττ (13 TeV) H à ZZ à llνν (13 TeV) Boosted Resonances (13 TeV) Higgs-to-Higgs H à ZZ à llqq (13 TeV) H à 2a (8 TeV) ZH, H à inv (13 TeV) X à Zγ (13 TeV) H à ZA (13 TeV) A à Zh(125) (13 TeV) 4

Recent √s = 8 TeV Results 5

2HDM+S: Search for h(125) à 2a Summary plot of μ/τ channels In a 2HDM+S model, there are 2 • singlet states: – CP-odd scalar a – CP-even s ! BR(h à BSM) < 0.34, so the decay to • 2a can be sizeable. ! Recent results from CMS for • h à 2a à 2b2μ and h à 2a à 2μ2τ! Current channels include: h à 2a à 2b2μ ( CMS-PAS-HIG-14-041 ) h à 2a à 4μ (CMS:Phys. Lett. B 752 (2016) 221) h à 2a à 2μ2τ (CMS-PAS-HIG-15-011, ATLAS:Phys. Rev. D92 (2015) 052002) h à 2a à 4τ (CMS-PAS-HIG-14-022, CMS:JHEP 01 (2016) 079) 6 h à 2a à 4γ (ATLAS:CERN-PH-EP-2015-187)

CMS-PAS-HIG-14-041 2HDM+S: Search for h(125) à 2a CMS-PAS-HIG-15-011 h à 2a à 2b2 μ: ! miss significance < 6 2 b-jets, 2 μ, E T |M bbμμ - 125|< 25 GeV ! Signal Modeling: Weighted sum of Voigt profile and Crystal ball. Background Modeling: Polynomial functions, fit to m μμ in data. ! h à 2a à 2 μ2τ ! 5 final states: μμτ e τ e , μμτ μ τ e, μμτ had τ e, μμτ had τ μ, μμτ had τ had ! |M ττμμ - 125|< 25 GeV (M μμ – M ττ )/M μμ < 0.8 |M vis eeμμ - 125| > 15 GeV ! Irreducible backgrounds from MC, reducible from data-driven 7 methods.

ATLAS:CERN-PH-EP-2015-290 2HDM: Search for H ± à tb CMS: JHEP 11 (2015) 018 tb) [pb] Predicted in models with extended Higgs ATLAS Observed limit (CLs) -1 s =8 TeV, 20.3 fb Expected limit (CLs) Sector (e.g. 2HDM): 10 + → gb → tH (tb) ± 1 σ + ! )xBR(H ± 2 σ Exp. limit with injected signal ✓ H ± dominantly produced in association m =300 GeV, xBR=1.65 pb σ + H + tH with a top quark. → 1 (gb ! σ H ± à tb is a dominant decay mode for ✓ mod- xBR m tan =0.5 σ β h heavy H ± . mod- σ xBR m tan β =0.7 -1 10 h mod- xBR m tan =0.9 σ β h 200 250 300 350 400 450 500 550 600 m [GeV] + H Search in lepton+jets final state. Fit is performed on 5 regions: • H T had in 4 Control Regions: [4j(2b), 5j(2b), ≥6j(2b), 4j(≥3b)] • BDT in 1 Signal Region: [≥5j(≥3b) BDT includes H t had , lead jet p T , m bb of 2 b-jets closest in ΔR, second Fox-Wolfram moment, and average ΔR between all b-jet pairs. 8

CMS-PAS-HIG-14-039 Higgs Triplets: Search for H ±± H ±± is predicted by models • with a Higgs triplet. ! This search is for • associated production or pair-produced left-handed H ±± into 3 or 4 leptons, respectively. 9

CMS-PAS-HIG-15-013 ATLAS: Phys. Rev. D 92, 092004 (2015) -1 CMS Preliminary, HH bb , 18.3 fb at s = 8 TeV → τ τ HH) [pb] Observed 95% upper limit 10 Scalar Resonance: H à hh à bbτ had τ had Expected 95% upper limit Expected limit 1 ± σ Expected limit 2 ± σ radion ( = 3 TeV) Λ → R radion ( = 1 TeV) Λ BR(X R 2 hadronic τ had and 2 jets 1 80 < m ττ < 140 GeV and 80 < m jj < 170 GeV m HH calculated using a kinematic fit × See Seth ! X) Zenz’s talk for Backgrounds → -1 10 non-resonant Multi-jet: Data-driven methods (pp analysis. Z/γ ∗ à τ had τ had : Embedding of µµ data events σ Others: Simulation ! -2 10 300 400 500 600 700 800 900 1000 Fit to three regions with 0, 1, or 2 b-tagged jets. m [GeV] X -1 CMS Preliminary CMS Preliminary -1 CMS Preliminary -1 18.3 fb (8 TeV) 18.3 fb (8 TeV) 18.3 fb (8 TeV) 2 10 [1/GeV] [1/GeV] [1/GeV] X HH bb X HH bb → → τ τ → → τ τ X → HH → bb τ τ 2jet0tag 2jet1tag 2jet2tag 10 Observed Observed Observed 1 Resonant Resonant Resonant Z Z → τ τ → τ τ Z → τ τ 10 t t t t t t 1 Electroweak Electroweak Electroweak 1 − 10 HH HH HH Multijets Multijets Multijets 1 dN/dm SM Higgs dN/dm SM Higgs dN/dm SM Higgs − 1 10 − 2 Uncertainty Uncertainty Uncertainty 10 − 1 10 2 − 10 3 − 10 − 2 10 3 − 4 10 − 10 3 − 4 − 5 − 10 10 10 200 300 400 500 600 700 800 900 1000 1100 1200 200 300 400 500 600 700 800 900 1000 1100 1200 200 300 400 500 600 700 800 900 1000 1100 1200 Data - Simulation Data - Simulation Data - Simulation 2 2 2 Simulation Simulation Simulation 1 1 1 0 0 0 200 400 600 800 1000 1200 200 400 600 800 1000 1200 200 400 600 800 1000 1200 10 m [GeV] m [GeV] m [GeV] HH HH HH

√s = 13 TeV Searches: Higgs to Fermions Fermionic Decays 11

Search for H ± à τν CERN-PH-EP-2016-056 Search is for the decays: H ± predicted in 2HDM/MSSM: ! ✓ H ± dominantly produced in association with a top quark. ! with the final ✓ H ± à τν decay channel represents a discriminating variable: clean signature and substantial BR (~10%) in several MSSM benchmarks. 11

CERN-PH-EP-2016-056 Search for H ± à τν Backgrounds: Event Selection ● Jet → τ fakes (multi-jet: data-driven) E T miss trigger ● Events with true τ (tt, W+jets: from MC, ≥3 jets including ≥1 b-tagged jet validated in CR) ● Events with lepton → τ fakes (top, 
 1 τ and no e or μ V+jets, diboson: Shape from MC, norm. E T miss > 150 GeV from data. ~5% of background.) m T > 50 GeV 60 � ) [pb] tan ATLAS Preliminary 55 -1 s = 13 TeV, 3.2 fb ν + τ 50 Observed (CLs) 1 → Expected (CLs) + BR(H 1 ± σ 45 2 ± σ + H hMSSM tan =60 β 40 ATLAS Preliminary × ) + -1 s = 13 TeV, 3.2 fb [b]tH 1 − 10 35 + H � � � ; hMSSM scenario Observed exclusion → 30 (pp Run 1 result Expected exclusion Observed ± 1 � 25 σ Expected 2 ± � − 2 10 200 400 600 800 1000 1200 1400 1600 1800 2000 20 m [GeV] 200 220 240 260 280 300 320 340 360 + H m [GeV] + 12 H

ATLAS-CONF-2015-061 Search for H/A à ττ H à ττ provides sensitivity in MSSM at high tanβ, and in 2HDM at the alignment limit. Analysis targets two channels with different τ decay modes. τ lep τ had Event Selection τ had τ had Event Selection ! ! Single τ had trigger Single lepton triggers 1 τ and 1 OS e/μ and Δφ(τ, e/μ ) > 2.4 2 τ had with OS charge M T (e/μ, MET) < 40 GeV or > 150 GeV Δφ(τ had,1 , τ had,2 ) > 2.7 In e-channel: m vis < 80 and > 110 GeV Final discriminant 14 in both channels

ATLAS-CONF-2015-061 Search for H/A à ττ Backgrounds ! ✓ True τ backgrounds (e.g. Z à ττ, tt) are taken from simulation. ! ✓ Jet à τ backgrounds (e.g. W+jets, multi-jets) are estimated using data-driven methods. gluon fusion b-associated No evidence for BSM Higgs, but sensitivity already exceeds run-1. 15

√s = 13 TeV Searches: Di-Higgs 16

ATLAS-CONF-2016-004 Search for H à hh à bbγγ Event Selection hh production can be resonantly enhanced by 2γ within 105 < m γγ < 160 GeV many BSM models (Singlet, MSSM, etc.). ! 2 central jets within 95 < m jj < 135 GeV bbγγ chosen due to high BR(h à bb) and clean • 2 (0) b-tag as SR (CR) at 85% efficiency γγ signature. ATLAS has also searched for hh à 4b, covered • bb 4-momenta scaled by m h /m bb in Max Bellomo’s talk tomorrow. |m γγ – m h | < 2σ(m γγ ) M bbγγ within window of 95% signal efficiency See Seth Zenz’s talk for non- resonant analysis. 17