Hints from Run 1 and Prospects from Run 2 at CMS. Qiang Li Peking University, Beijing, China

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1 Hints from Run 1 and Prospects from Run 2 at CMS Qiang Li Peking University, Beijing, China

2 LHC-CMS 2

3 : Successful Run1 3

4 : Successful Run1 and Standard Model Rare B decay, Top mass, SM test over vast magnitudes 4

5 : Successful Standard Model up to? CMS/ATLAS Measured Higgs mass works well in SM global fit Higgs self coupling λ goes to zero or negative at around GeV JHEP08(2012)098 5

6 TeV Scale New Physics: Many hints and candidates Fine Tuning Dark matter Gauge Unification Flavor structure Baryon Asymmetry SUSY Extra Dimensions Extra Gauge Symmetry: W, Z Exotic heavy Quarks, Leptons, Leptoquarks Compositeness: contact interaction 6

7 BSM Searches Resonance Shape Rate lq, lγ, q γ, l+met as well 7

8 CMS Publications Impossible to cover all Will focus on CMS recent progress from Higgs SUSY Exotics B2G especially those related to BSM DM will be discussed in detail by T. Kamon 8

9 Higgs Status: Mass, Couplings Phys. Rev. Lett. 114, (2015) Eur. Phys. J. C 75 (2015) 212 Combination Significance (m H = GeV) Expected (post-fit) fit) Observed H ZZ tagged 6.3 σ 6.5 σ H γγ tagged 5.3 σ 5.6 σ H WW tagged 5.4 σ 4.7 σ H ττ tagged 3.9 σ 3.8 σ H bb tagged 2.6 σ 2.0 σ H μμ tagged <0.1 σ 0.4 σ 9

10 Higgs Properties: Width, Spin, CP Phys. Lett. B 736 (2014) 64 arxiv:

11 Heavy SM-like/BSM Higgs Spin-2 arxiv: arxiv: H WW/ZZ, interpreted also in EWK Singlet Spin-0 CMS PAS-HIG A Zγ Pseudo-scalar in SU(4) inspired model H γγ, interpreted also in 2HDM 11

12 Light Higgs in NMSSM CMS PAS-HIG produced in SUSY cascades and decaying into bbar arxiv: h aa + X 4μ + X In NMSSM or dark SUSY 12

13 Higgs LFV decay: first direct search arxiv: H μτ e μτ h 0, 1, 2Jets 2.4σ excess at MH=125GeV B(H μτ)<1.51% at 95%C.L. Limit also given for LFV Yukawa Couplings 13

14 Charged Higgs CMS PAS HIG CMS PAS HIG CMS PAS HIG H τv + t Jets Or H τv + t μ + J Or H tb with both t->l 14

15 X-> HH or Zh/H/A A Zh in llbb arxiv: X= spin 0 Radion or spin 2 KK Graviton arxiv: H/A ZA/H in llbb or llττ CMS PAS HIG

16 SUSY See more in Teruki Multi - jets, b-jets, leptons, MET HT, edges, alphat, Razor, MT2 Inclusive searches, 3 rd -generation, EWK searches, VBF, RPV, long lived particle CMSSM or SMS as guidance Single production mode and 1-or-2 steps decay with BR~100%, other SUSY particles are heavy 16

17 3 rd Generation Stop typical limits reach 700 GeV a number of holes in the coverage left, corresponding to compressed mass spectra resulting in experimental challenges 17

18 STOP Compressed Spectrum m t m x < m w Single lepton Hard ISR jet, high missing energy, and one or two soft lepton CMS PAS SUSY dilepton 18

19 Dilepton Edge or Z-Peak JHEP 04 (2015) 124 Unbinned max likelihood fit to Mll: a small excess of 2.4σ with an edge at ~80 GeV 19

20 Non-SUSY: Exotica and B2G 20

21 Non-SUSY: Exotica and B2G 21

22 Z ll, τ τ JHEP 04 (2015) 025 CMS PAS EXO Z ll SSM Z <2.9TeV, RS G <2.7TeV for k/c=0.1 Z ll Z τe τμ Non-resonance also covered: CI, ADD 22

23 W lv, τv Phys. Rev. D 91 (2015) CMS PAS-EXO W τv SSM W <3.28TeV -> Dark Matter interpretation 23

24 Di-jet resonance Phys. Rev. D 91, (2015) gg, qq, gq resonance: narrow or wide Also for final states including b Leading 2 jets as seeds -> 2 wide jets (DR<1.1) SSM W, Z < 2TeV RS G <1.6TeV Excited b* < TeV 24

25 Di-jet angular distribution: Compositeness and ADD Phys. Lett. B 746 (2015) 79 Previous inclusive jet pt search: Phys. Rev. D 87 (2013)

26 Z TT arxiv: ,1,2 lepton category b-tag category CA8 CMS Top Tagging for high mass CA15 HEPToptagger for low mass Narrow width 1% Wider width 10% 26

27 Vector-like Quark has only vector couplings with the W and Z bosons, thereby evading many electroweak precision tests, e.g. in LH model pp T T bw: tz: th T th: 100% bw: tz: th 50%: 25%: 25% arxiv: T th full hadronic: Top and H tagging Phys. Lett. B 729 (2014) or more lepton catagory Boosted H tagging For the first time 27

28 Di-boson Resonance: W-/ H-tagging JHEP 1412 (2014) 017 CMS PAS BTV W-tagging: Pruning, CA8, Nsubjettiness H-tagging: jet/subjet b-tagging TTbar control region-> Scale Factor 28

29 Di-boson Resonance: VV lvj, llj, jj JHEP 08 (2014) 173, JHEP 08 (2014) 174 llj lvj + llj lvj + llj + jj 29

30 Di-boson Resonance: VH VH: lvbb, llττ, full had CMS PAS EXO arxiv: arxiv: EXO Global significance 1.9σ Heavy Vector Triplet Model: JHEP 1409 (2014)

31 Run2 and future 2015 Phase Days Physics efficiency Initial low luminosity luminosity run 50 ns intensity ramp-up Integrated luminosity 7 20% few pb % 0.5 fb-1 Run2 Start on June/03, 2015, with stable beams at energy 6.5TeV 25 ns phase beta*=80 cm 70 30% 8 fb-1 31

32 Run2 and future beyond 2025 and up to 2035: HL-LHC 3000fb-1 Mike Lamont, Moriond

33 Collider Reach Run2 1fb-1, already surpass Run1 at ~3TeV 10fb-1 start overtake Run1 Run2 100fb-1 Z 3TeV 5-6TeV 33

34 CMS Exotics Projecture arxiv:

35 CMS SUSY Projecture arxiv:

36 Summary New Physics Searches at the CMS: top down: guided by SUSY and other models bottom up: possible corners/final state combination Higgs becomes a tool for new physics search Rich results from Run1, hints for Run2. A few excesses here and there to follow. Run2 will definitely tell us more Thank you! 36

37 Higgs invisible decay Eur. Phys. J. C 74 (2014) 2980 CMS PAS HIG Combined Br H inv < 55% 44% at 95% C. L. VBF result recently updated to <57% from previous <65% Impact on DM Nucleon Xsec in Higgs portal models 37

38 VBF SUSY CMS PAS SUSY at least 2 leptons, large missing transverse momentum, and 2 jets with a large pseudorapidity gap compressed mass spectra 38

39 SUSY Searches at CMS Can only highlight some recent results 39

40 Results of the edge-search counting experiment for event yields in the signal regions. The statistical and systematic uncertainties are added in quadrature, except for the flavor-symmetric backgrounds. Low-mass refers to 20 < mll < 70 CMS.GeV, on-z to 81 < mll < 101 CMS.GeV, and high-mass to mll > 120 CMS.GeV. 40

41 41

42 RS Graviton: γ γ CMS PAS EXO WZ->llv resonance Phys. Lett. B 740 (2015) 83 RS G <2.78TeV for k/c=0.1 42

43 Excited quark: q+γ Phys. Lett. B 738 (2014) 274 Focus on Λ = M q And f s = f = f ~O(1) Bkg fit by 43

44 Excited lepton: l+γ CMS PAS EXO Phys. Lett. B 720 (2013) 309 L-shape l l + γ closed for f = f 44

45 Fat Jet at CMS: an incomplete history 7TeV Z ->ttbar: Proposed Jet Pruning, C-A 0.8 Jet, TTbar control JHEP 1209 (2012) 029, Erratum-ibid (2014) 132 7TeV WZ/ZZ resonance: Jet mass, mass drop JHEP 1302 (2013) 036 Dijets and V+jets, jet mass and substructure at 7 TeV: Comprehensive overview of various jet grooming techniques JHEP 1305 (2013) 090 8TeV WW/WZ/ZZ resonance: W-tagging, Pruning, CA8, Nsubjettiness JHEP 1408 (2014) 173 ; JHEP 1408 (2014) 174 W-tagging Summary: JHEP 1412 (2014) 017 Top tagging. Groomed Jet more stable with PU 45

46 Efficiency of the pruned jet mass cut and the tau2/tau1 cut combined with the pruned jet mass cut on WW signal samples as a function of pt. Efficiency of reconstructing either the simulated W or simulated decaying quarks from the W with a single generator level CA8 jet or two generator level AK5 jets. Matching of generator level jets to the simulated W and simulated quarks are required within deltar <

47 Fraction of jets passing the pruned jet mass and tau2/tau1 cuts in data and simulation as a function of pt. The data over simulation ratio is shown for the combination of the pruned jet mass and tau2/tau1 cuts. 47

48 VV lvj VV llj The typical width of the Gaussian core is about 3% 5% of the nominal mass in the ll+v-jet channel or 4% 6% for the lv+v-jet channel 48

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50 VV dijet 50

51 Higgs Tagging: a bit beyond W-tagging 51

52 CMS PAS EXO Final M WH distribution 52

53 Long Lived Particles Eur. Phys. J. C 75 (2015) 151 Phys. Rev. D 91 (2015) Phys. Rev. D 91 (2015) Stopped in the calorimeter: R-hadrons using the time intervals between LHC beam crossings Displaced dilepton: H XX, X l + l ; q q x 0, x 0 l + l v Displace dijet: H XX, X q q; q q x 0, x 0 jjμ Set limits on lifetime of the long-lived particle 53