The Higgs profile at the LC

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1 1th International Conference on Supersymmetry and Unification of Fundamental Interactions June 17-23, 22, Hamburg from SM to SUSY Marco Battaglia CERN, Geneva, Switzerland Page 1

2 Linear Collider Projects and R&D Page 2

3 LC Project Parameters Parameters TESLA NLC CLIC s (GeV) SC Warm TBA L (1 34 /cm 2 s) RF (GHz) f rep (Hz) N b /Pulse t b (ns) σ y /σ z 5/3 4.6/12 1./3 (n/µm) 2.8/11 Grad. (MV/m) Length (km) 22/33 9/26 2/28 L (1 34 ) TESLA NLC CLIC Ecm (TeV) Page 3

4 The TESLA Project Use of SC cavities offers high luminosity with more relaxed alignment requirements; Highest s wrt Cavity Gradient: 5 GeV 23 MV/m Demonstrated 8 GeV 35 MV/m R&D A.Wagner s Friday Lecture Page 4

5 CLIC R&D towards Multi-TeV Collisions: C L I C Multi-TeV e + e collisions will require efficient energy transfer at very high gradients; Two-beam acceleration scheme represents unique opportunity to extend the physics at e + e colliders at constituent energies of the order of, and beyond, the LHC energy frontier. Page 5

6 Observing the Higgs Boson Columbus, 1492 Page 6

7 Model Independent Higgs Boson Observation Higgs Signal from Recoil Mass to Z µ + µ e Z H X X Number of Events / 1.5 GeV Data Z H µµ X 2 m H = 12 GeV Recoil Mass [GeV] e + Z l + Nb. of Higgs Bosons Observable at LC in 1.5 Years in Model-Independent Way M H s 35 GeV GeV GeV GeV GeV Max M H l Page 7

8 The Neutral Higgs Boson Profile Ramusio, 1556 Page 8

9 Number of Events / 1.5 GeV M H Data Z H µµ X 2 m H = 12 GeV Recoil Mass [GeV] The Higgs Boson Profile SM Higgs width (GeV) Γ H g HVV m H (GeV) H e + e - Events / 5 fb -1 4 a) Simulated Data WW Fusion HZ Background 3 Fit result s = 35 GeV Missing mass (GeV) J PC - Z g Hff events/ V( Φ) Events/1 fb cos(θ z ) N event 12 1 light Quark Tag c Quark Tag b Quark Tag NN output Page 9

10 Probing the Higgs Mechanism LC has unique potentialto verify that the Higgs boson does its job of providing gauge bosons, quarks and leptons with their masses; g HXX g HY Y M X M Y SM Higgs Branching Ratio 1 1 bb ττ gg cc 1 2 WW 1 3 γγ M (GeV) H Important to ensure sensitivity over wide mass range and a significant accuracy for all particle species. Page 1

11 Couplings to Gauge Bosons σ e + e HZ Determination of Higgstrahlung crosssection to measure H coupling to Z and a key input to extract absolute BRs; use dilepton recoil mass from Z l + l decay and impose beam-spot constraint to improve σ p /p; analysis is flavour blind and sensitive to non-standard decay modes such as H invisible. M H Fit σ HZ l + l (fb) δ stat % GeV /5 fb 1 /5 fb ±.13(stat)±.12(syst) ± ±.12(stat)±.1(syst) ± ±.11(stat)±.8(syst) ± 3. P Garcia et al. LC-PHSM-21-54, T Abe et al. hep-ex/1656 σ Zh µµx (fb) ll Recoil Mass for e + e Z H l + l X NLC at 35 GeV (µ + µ X) Events/2.(GeV) (a) Z Recoil Mass (GeV) e + e Zh µ + µ X SM prediction 35 GeV 5 GeV 115 GeV 12 GeV 14 GeV 16 GeV WW ZZ (a) Higgs Mass (GeV) Page 11

12 Couplings to Gauge Bosons σ e + e WWν ν Hνν Determination of WW-fusion reaction σ e+ e WWν ν Hν ν to measure H coupling to W and a key input to extract Γ H ; Select b-tagged hadronic events with large E miss, M miss at s = 35 GeV; Extract σ Hνν from χ 2 fit to missing mass distribution: Overlapped γγ hadrons bkg. suppressed by i.p. analysis if σ beam z >> σ ip z Events / 5 fb -1 Jet-Jet Missing Mass for e + e H ν ν b bν ν a) Simulated Data WW Fusion HZ Background Fit result s = 35 GeV Missing mass (GeV) K.Desch, N.Meyer, LC-PHSM δ(σ M H Fitted Evts. Hνν ) σ Hνν GeV / 5 fb 1 / 5 fb ± 83 ± 2.6 % ± 71 ± 5.3 % ± 66 ± 1.3 % Page 12

13 The Generation of Mass The Quark Sector Compute uū + d d + s s, c c and b b di-jet flavour tagging probs Fit hadronic branching fractions: BR(H b b)/br(h hadrons), BR(H c c)/br(h hadrons) [BR(H gg)/br(h had.)] [BR(H WW)/BR(H had.)] binned likelihood fit to bkg subtracted di-jet probs: Events/1 fb -1 Events/1 fb M H = 12 GeV, s = 35 GeV light Quark Tag c Quark Tag b Quark Tag M H = 16 GeV, s = 35 GeV BR(H(12) X) δbr/br b b.24 c c.85 gg light Quark Tag c Quark Tag b Quark Tag M B hep-ph/ JC Brient, LC-PHSM-22-3 J Brau et al, Snowmass 21 Procedings Page 13

14 The Generation of Mass The Lepton Sector BR(H τ + τ ) with τ-id based on multiplicity and kinematics; BR(H µµ) observable as rare decay at TeV-class and multi-tev LC; Evts. / 1 ab Evts. / 5 ab µ + µ Mass (GeV) M H 12 GeV 14 GeV 15 GeV δg Hττ /g Hττ (at.5 TeV).27.5 δg Hµµ /g Hµµ (at.8 TeV) δg Hµµ /g Hµµ (at 3. TeV) M B, hep-ph/ and JC Brient, LC Note µ + µ Mass (GeV) M B and A De Roeck, hep-ph/11137 Test g Hµµ /g Hττ coupling ratio to.5-.8 accuracy at multi-tev LC, compared to.3-.4 at FMC for 12 <M H < 14 GeV. Page 14

15 Higgs Quantum Numbers Spin, parity and charge-conjugation quantum numbers J PC of Higgs bosons can be determined at LC in model-independent way. Observation of γγ H or H γγ sets J 1and C =+. Angular dependence dσ ZH dθ sin 2 θ and rise of σ ZH β s (M H + M Z ) 2 allows to determine J P = + and distinguish SM H from CP-odd + state A, oracp-violating mixture. 15 events/.1 1 cross section (fb) 1 J= J= J= s (GeV) cos(θ z ) M.Schumacher Page 15

16 Invisible Decay Modes Severaltheoreticalmodels motivate this analysis (possibly SUSY decays χ χ, but also signature from radion-higgs mixing, stealth models,...). Invisible Higgs decays detectable from visible decay modes (indirect) and analysis of system recoiling against the Z in e + e HZ (direct); BR / BR 1-1 ind. method M H = 12 GeV M H = 14 GeV M H = 16 GeV BR(H--INV.) R van Kooten and M Schumacher Preferable to perform analysis at low s to reduce bkg. (ZZ, WW) Page 16

17 Reconstruction of the Higgs Potential Fundamentaltest of shape of Higgs potential through independent determination of g HHH in double Higgs production (HHZ and Hνν): V( Φ) λ from M H λ from g HHH V (Φ Φ) = λ(φ Φ 1 2 v2 ) 2 g HHH = 3 2 M 2 H v σ(e + e - HHZ) (fb) e + e HHZ Φ σ(e + e - HHυυ) (fb) e + e HHνν g HHH /g HHH (SM) g HHH /g HHH (SM) Page 17

18 .5-.8 TeV LC for M H = 12 5TeVCLICforM H = Evts 18 Evts HH Mass (GeV) s (TeV) Counting Fit.5 ±.23 (stat) ±.2 (stat).8 ±.35 (stat) ±.29 (stat) C Castanier et al. hep-ex/1128, M B et al. hep-ph/ cos θ * M H (GeV) Fit 12 ±.75 (stat) 18 ±.82 (stat) Page 18

19 Precision Investigation of the Higgs Profile at a TeV-LC M H (GeV) δ(x)/x LC-5-LC-3.5ab 1-5ab 1 M H (3-5) 1 4 Γ tot g HWW g HZZ g Htt g Hbb g Hcc g Hττ g Hµµ CP test 12.3 g HHH g b /g b (SM) g W /g W (SM) MSSM prediction: 2 GeV < m A < 4 GeV 4 GeV < m A < 6 GeV 6 GeV < m A < 8 GeV 8 GeV < m A < 1 GeV LC 95% CL LC 1σ m H = 12 GeV m H = 12 GeV 2 GeV < m A < 3 GeV 1 GeV < m A < 2 GeV g c /g c (SM) MSSM prediction: 3 GeV < m A < 1 GeV LHC 1σ LC 95% CL LC 1σ g top /g top (SM) M B, K Desch hep-ph/11165 Page 19

20 What if the Higgs is heavier? Analyse HZ l + l, q q recoilmass at 5 GeV and Hν ν at 8 GeV; Extract M H, Γ H and σ from fit to recoilmass, H WW and ZZ branching fractions from fit to jet-jet mass in HZ and H b b in Hν ν: M H GeV δx/x LC-5/8.5/1 ab 1 M H Γ H σ(e + e HZ) 24.4 BR(H ZZ) 24.1 BR(H WW) 24.7 BR(H b b) 2.16 BR(H b b) N.Meyer, K.Desch, M.B. LC Notes in preparation Page 2

21 An Extended Higgs Sector Blaeu, 1635 Page 21

22 The Nature of the Higgs Boson Indirect sensitivity to SUSY Higgs through highly accurate determinations of neutralhiggs boson couplings; Direct observation of heavy Higgs bosons produced in e + e and γγ collisions at LC and study of their properties: e + e HZ e + e H A γγ H, A BR MSSM / BR SM Events/1 GeV o o e e H A M = M = 3 GeV H A HA tt 4 fermions (b) σ(γγ bb _ ) [fb] cosθ <.5 tanβ = 7 M A = 3 GeV = ±2 GeV tot signal A+H A H.1 background M A (GeV/c 2 ) Reconstructed Mass (GeV) E ee [GeV] Page 22

23 ffima (GeV) Telling the SM H from a SUSY h Higgs couplings to fermions may reveal his SM or SUSY nature: g Hf f g Hf f m f m f in SUSY couplings to up-like and down-like fermions shifted w.r.t. their SM predictions: BR(h f ufu ) tan β SM/MSSM separation BR(h f d fd ) 1 tan 2 α tan 2 β (M h 2 M A 2 )2 (MZ 2 +M A 2 ) M A (GeV) MA (GeV) Page 23

24 isusy sbottom-gluino and stop-higgsino loops induce a shift of the effective b-quark mass in the hbb couplings: m b µm g tan βf(m b1,m b2,m g ) BR(h b b, µµ) vs.m A BR(h µµ)/br SM tan β m A (GeV) M.Carena M.B., M.Spira Page 24

25 MSSM Higgs Sector at LHC and TeV-class LC tan β TESLA LC e + e 8 GeV e + e 5 GeV γγ 8 GeV γγ >H/A >bb 2 e+e >H+H >tbtb 1 5 e+e >HA >bbbb e+e >ZH >ff ff Indirect g Hff LEP mh max Summer M (GeV) A Page 25

26 Charged Higgs Bosons H ± Production cross section at threshold β 3 and independent on model parameters; Main decay mode above threshold H tb results in challenging multi-jet final state: H + H t b tb at 3 TeV σ(e + e - H + H - ) in fb No ISR, no beamstrahlung TeV-class LC with ISR and beamstrahlung σ(e + e - H + H - ) in fb No ISR, no beamstrahlung Multi-TeV LC with ISR and beamstrahlung m(h) in GeV m(h) in GeV S.Kraml s Parallel Talk on Thursday Page 26

27 s =.8 TeV s =3. TeV N / 5 GeV 5 4 M H ±=3 GeV N / 2 GeV M H ±=88 GeV S+B after kinematical fit S+B after kinematical fit with W qq only m rec (H) = ± 7.7 GeV m rec (H) in GeV m rec (H) in GeV s =.8 TeV s =3. TeV M H ± = 3 GeV M H ± = 88 GeV M H ±.1.1 σ H+ H BR(H tb).8.15 M.B., A.Kiiskinen, A.Ferrari, hep-ex/11215 Page 27

28 Neutral Heavy Higgs Bosons H, A Events/1 GeV e + e H A b bb b M A = 3 GeV at s =.8TeV + - e e H A M = M = 3 GeV H HA tt o o A 4 fermions (b) Reconstructed Mass (GeV) M H ± = 26 GeV M H ± = 34 GeV M A.1.2 σ H A BR2 (H /A b b).2.6 A.Andreazza, C.Troncon M.Mühlleitner s Parallel Talks on Tuesday Page 28

29 Heavy Higgs Bosons at the Photon Collider Opportunity to operate a γγ Collider at the LC may significantly extend the reach in mass in Heavy Higgs boson searches through single production γγ H, γγ A : 1 <σ(γγ bb _ )> [fb] tgβ = 7 = ±3 GeV cosθ <.5 w/o SUSY σ(γγ bb _ ) [fb] cosθ <.5 tanβ = 7 M A = 3 GeV = ±2 GeV tot signal A+H 1-1 background M 2 /µ = 2/2 2/ 2 GeV A.2 H M A [GeV].1 background E ee [GeV] M.M.Mühlleitner et al. PLB 58 (21) S.Söldner-Rembold s Parallel Talk on Thursday Page 29

30 SUSY Higgs Self-Couplings 1.5 MSSM Higgs Self Couplings Normalized to SM g HHH hhh hhh Regions of LC Sensitivity tgβ sensitivity to λ hhh ee Zhh s = 5 GeV HAA hh+h- HH+H- haa hhh M A [GeV] tgβ sensitivity * to λ Hhh ee Ahh s = 1 TeV HHH F.Boudjema, A.Semenov hep-ph/21219 MA M A [GeV] A.Djouadi et al. hep-ph/1169 Page 3

31 NMSSM Introduction of additionalhiggs singlet may be motivated for natural explanation of value of µ term in MSSM Higgs potential; Interesting phenomenology with two scalar Higgs bosons possibly within reach of a TeV-class LC one light pseudoscalar and four heavy bosons almost degenerate in mass: 6 5 Charged CP even CP odd ZZH 1 ZZH 2 ZZH 3 Higgs Mass (GeV) NMSSM g / SM gzzh ZZH M A (GeV) D.J.Miller D.J.Miller s Parallel Talk on Tuesday M A (GeV) Page 31

32 The Higgs Boson and the Radion Radion represents quantum excitation of brane separation in Randall-Sundrum model, which offers a solution to hierarchy problem; By mixing with the Higgs field, Radion modifies BR(H X): BR(H gg) BR(H f f) J.Hewett, T.Rizzo, hep-ph/22155 T.Rizzo and J.Gunion s Parallel Talks on Monday Page 32

33 Conclusions Münster, 1581 Page 33