Supersymmetry at the LHC

Transcription

1 Supersymmetry at the LHC Georg Weiglein IPPP Durham Heidelberg, 08/2007 Introduction Properties of SUSY theories What is the scale of Supersymmetry? SUSY Higgs physics at the LHC SUSY processes at the LHC Conclusions Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.1

2 Introduction The LHC will open up the new territory of TeV-scale physics What can we learn from exploring the TeV scale? Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.2

3 Introduction The LHC will open up the new territory of TeV-scale physics What can we learn from exploring the TeV scale? How do elementary particles obtain the property of mass: what is the mechanism of EWSB? Do all the forces of nature arise from a single fundamental interaction? Are there more than three dimensions of space? Are space and time embedded into a superspace? Can dark matter be produced in the laboratory?... Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.2

4 What is the mechanism of electroweak symmetry breaking? Standard Model (SM), SUSY,... : Higgs mechanism, elementary scalar particle(s) [see R. Barbieri s talk] Strong electroweak symmetry breaking (technicolour,... ): new strong interaction, non-perturbative effects, resonances,... Higgsless models in extra dimensions: boundary conditions for SM gauge bosons and fermions on Planck and TeV branes in higher-dimensional space New phenomena required at the TeV scale Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.3

5 The Standard Model cannot be the ultimate theory The Standard Model does not include gravity breaks down at the latest at M Planck GeV Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.4

6 The Standard Model cannot be the ultimate theory The Standard Model does not include gravity breaks down at the latest at M Planck GeV Hierarchy problem : M Planck /M weak How can two so different scales coexist in nature? Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.4

7 The Standard Model cannot be the ultimate theory The Standard Model does not include gravity breaks down at the latest at M Planck GeV Hierarchy problem : M Planck /M weak How can two so different scales coexist in nature? Via quantum effects: physics at M weak is affected by physics at M Planck Instability of M weak Would expect that all physics is driven up to the Planck scale Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.4

8 The Standard Model cannot be the ultimate theory The Standard Model does not include gravity breaks down at the latest at M Planck GeV Hierarchy problem : M Planck /M weak How can two so different scales coexist in nature? Via quantum effects: physics at M weak is affected by physics at M Planck Instability of M weak Would expect that all physics is driven up to the Planck scale Nature has found a way to prevent this The Standard Model provides no explanation Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.4

9 Hierarchy problem: how can the Planck scale be so much larger than the weak scale? Expect new physics to stabilise the hierarchy Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.5

10 Hierarchy problem: how can the Planck scale be so much larger than the weak scale? Expect new physics to stabilise the hierarchy Supersymmetry: Large corrections cancel out because of symmetry fermions bosons Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.5

11 Hierarchy problem: how can the Planck scale be so much larger than the weak scale? Expect new physics to stabilise the hierarchy Supersymmetry: Large corrections cancel out because of symmetry fermions bosons Extra dimensions of space: Fundamental Planck scale is TeV (large extra dimensions), hierarchy of scales is related to a warp factor ( Randall Sundrum scenarios) Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.5

12 Properties of SUSY theories Supersymmetry: fermion boson symmetry, leads to compensation of large quantum corrections Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.6

13 The Minimal Supersymmetric Standard Model (MSSM) Superpartners for Standard Model particles: [ u,d,c,s,t,b ] [ũ, d, c, s, t, b ] L,R [ e,µ,τ ] L,R L,R [ẽ, µ, τ ] L,R [ νe,µ,τ ] [ νe,µ,τ ] L Spin 1 2 L Spin 0 g W ±,H ± }{{} γ,z,h 0 1,H 0 2 }{{} Spin 1 / Spin 0 g χ ± 1,2 χ 0 1,2,3,4 Spin 1 2 Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.7

14 The Minimal Supersymmetric Standard Model (MSSM) Superpartners for Standard Model particles: [ u,d,c,s,t,b ] [ũ, d, c, s, t, b ] L,R [ e,µ,τ ] L,R L,R [ẽ, µ, τ ] L,R [ νe,µ,τ ] [ νe,µ,τ ] L Spin 1 2 L Spin 0 g W ±,H ± }{{} γ,z,h 0 1,H 0 2 }{{} Spin 1 / Spin 0 g χ ± 1,2 χ 0 1,2,3,4 Spin 1 2 Two Higgs doublets, physical states: h 0,H 0,A 0,H ± Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.7

15 The Minimal Supersymmetric Standard Model (MSSM) Superpartners for Standard Model particles: [ u,d,c,s,t,b ] [ũ, d, c, s, t, b ] L,R [ e,µ,τ ] L,R L,R [ẽ, µ, τ ] L,R [ νe,µ,τ ] [ νe,µ,τ ] L Spin 1 2 L Spin 0 g W ±,H ± }{{} γ,z,h 0 1,H 0 2 }{{} Spin 1 / Spin 0 g χ ± 1,2 χ 0 1,2,3,4 Spin 1 2 Two Higgs doublets, physical states: h 0,H 0,A 0,H ± General parametrisation of possible SUSY-breaking terms free parameters, no prediction for SUSY mass scale Hierarchy problem expect observable effects at TeV scale Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.7

16 Supersymmetry (SUSY) SUSY: unique possibility to connect space time symmetry (Lorentz invariance) with internal symmetries (gauge invariance): Unique extension of the Poincaré group of symmetries of D = 4 relativistic quantum field theories Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.8

17 Supersymmetry (SUSY) SUSY: unique possibility to connect space time symmetry (Lorentz invariance) with internal symmetries (gauge invariance): Unique extension of the Poincaré group of symmetries of D = 4 relativistic quantum field theories Local SUSY includes gravity, called supergravity Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.8

18 Supersymmetry (SUSY) SUSY: unique possibility to connect space time symmetry (Lorentz invariance) with internal symmetries (gauge invariance): Unique extension of the Poincaré group of symmetries of D = 4 relativistic quantum field theories Local SUSY includes gravity, called supergravity Lightest superpartner (LSP) is stable if R parity is conserved Candidate for cold dark matter in the Universe Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.8

19 Supersymmetry (SUSY) SUSY: unique possibility to connect space time symmetry (Lorentz invariance) with internal symmetries (gauge invariance): Unique extension of the Poincaré group of symmetries of D = 4 relativistic quantum field theories Local SUSY includes gravity, called supergravity Lightest superpartner (LSP) is stable if R parity is conserved Candidate for cold dark matter in the Universe Gauge coupling unification, M GUT GeV neutrino masses: see-saw scale.01.1m GUT Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.8

20 SUSY breaking MSSM: no particular SUSY breaking mechanism assumed, parametrisation of possible soft SUSY-breaking terms relations between dimensionless couplings unchanged cancellation of large quantum corrections preserved Most general case: 105 new parameters Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.9

21 SUSY breaking MSSM: no particular SUSY breaking mechanism assumed, parametrisation of possible soft SUSY-breaking terms relations between dimensionless couplings unchanged cancellation of large quantum corrections preserved Most general case: 105 new parameters Strong phenomenological constraints on flavour off-diagonal SUSY-breaking terms Good phenomenological description for universal SUSY-breaking terms ( diagonal in flavour space) Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.9

22 Simplest ansatz: the CMSSM Assume universality at high energy scale (M GUT, M Pl,... ) Universal scalar masses: m 2 = m 2 0 Universal gaugino masses: M i = m 1/2 ( GUT relation ) Universality of soft-breaking trilinear terms: L tri = A 0 (H U Qy u ū + H D Qy d d + HD Ly l ē) y u, y d,... are the same matrices that appear in Yukawa couplings ( proportionality ) Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.10

23 Radiative electroweak symmetry breaking [see W. Bernreuther s talk] Universal boundary conditions at GUT scale, renormalisation group running down to weak scale ~ l ~ g H q ~ W ~ H large corrections from top-quark Yukawa coupling m 2 H u driven to negative values ew symmetry breaking B ~ emerges naturally at scale 10 2 GeV for 100 GeV < m t < 200 GeV Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.11

24 The Constrained MSSM (CMSSM) Universality ansatz results in five parameters, if possible phases are ignored: m 2 0, m 1/2, A 0, b, µ Require correct value of M Z µ, b given in terms of tan β v u /v d, sign µ CMSSM characterised by m 2 0, m 1/2, A 0, tanβ, sign µ Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.12

25 SUSY-breaking scenarios Hidden sector : Visible sector: SUSY breaking MSSM Gravity-mediated : SUGRA Gauge-mediated : GMSB Anomaly-mediated : AMSB Gaugino-mediated... SUGRA: mediating interactions are gravitational GMSB: mediating interactions are ordinary electroweak and QCD gauge interactions AMSB, Gaugino-mediation: SUSY breaking happens on a different brane in a higher-dimensional theory Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.13

26 SUGRA / CMSSM phenomenology SUGRA with universality assumptions CMSSM m 0, m 1/2, A 0 : GUT scale parameters Spectra from renormalisation group running to weak scale Lightest SUSY particle (LSP) is usually lightest neutralino Gaugino masses run in same way as gauge couplings gluino heavier than charginos, neutralinos 800 m [GeV] H 0, A 0 H± χ 0 χ χ ± 2 g ũ L, d R ũ R, d L t 2 b2 b1 t 1 Typical CMSSM scenario (SPS 1a benchmark scen.): h 0 ll ν l lr τ 2 τ 1 χ 0 2 χ 0 1 χ ± 1 0 Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.14

27 GMSB phenomenology Gaugino and scalar masses arise from loop contributions involving messenger fields Typical mass hierarchy in GMSB scenario between strongly interacting and weakly interacting particles α 3 /α 2 /α 1 LSP is always the gravitino (also possible in msugra) next-to-lightest SUSY particle (NLSP): χ 0 1 or τ 1 can decay into LSP inside or outside the detector GMSB scenario with τ NLSP (SPS 7 benchmark scen.): 1000 m [GeV] H 0, A 0 H± h 0 ll ν l lr τ 2 τ 1 χ 0 4 χ 0 3 χ 0 2 χ 0 1 χ ± 2 χ ± 1 g q L q R t 2 b2 b1 t 1 Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.15

28 Meta-stable vacua Suppose we live in a SUSY-breaking meta-stable vacuum, while the global minimum has exact SUSY Recent developments: meta-stable vacua arise as generic feature of SUSY QCD with massive flavours Meta-stable SUSY-breaking vacua are generic in local SUSY / string theory, can have cosmologically long life times [Intriligator, Seiberg, Shih 07,... ] Large activity in model building Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.16

29 Summary on SUSY-breaking scenarios We have no Standard Model of SUSY breaking There are many possibilities We have to be prepared for a wide range of possible SUSY phenomenology Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.17

30 Generic features of SUSY theories Most general gauge-invariant and renormalizable superpotential with chiral superfields of the MSSM: V = V MSSM λijk L i L j E k + λ ijk L i Q j D k + µ i L i H u + 1 }{{} 2 λ ijk U i D j D k }{{} violate lepton number violates baryon number If both lepton and baryon number are violated rapid proton decay Minimal choice (MSSM) contains only terms in the Lagrangian with even number of SUSY particles additional symmetry: R parity all SM particles have even R parity, all SUSY particles have odd R parity Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.18

31 Phenomenological consequences of R parity conservation SUSY particles can only be pair-produced, e.g. gg g g Decay of SUSY particles into SM particles + odd number of SUSY particles Lightest SUSY particle (LSP) is stable All SUSY particles will eventually decay into LSP Decay cascades of heavy SUSY particles LSP stable some LSP must have survived from Big Bang Weakly interacting massive particle ( WIMP ) (otherwise ruled out from bounds on exotic isotopes etc.) Candidate for cold dark matter in the Universe LSP neutral, uncoloured leaves no traces in collider detectors Typical SUSY signatures: missing energy Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.19

32 Relations between SUSY parameters Symmetry properties of MSSM Lagrangian (SUSY, gauge invariance) give rise to coupling and mass relations Soft SUSY breaking does not affect SUSY relations between dimensionless couplings E.g.: gauge boson fermion coupling = gaugino fermion sfermion coupling for U(1), SU(2), SU(3) gauge groups Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.20

33 Squark and slepton mixing ( M 2 t M t = + m 2 L t + M2 Z c 2β(Tt 3 Q ts 2 W) m t X q m t X q M 2 t R + m 2 t + M2 Z c 2βQ t s 2 W ) m t 1,m t 2,θ t M b = ( M + m 2 bl 2 b + M2 Z c 2β(Tb 3 Q bs 2 W) m b Xq ) m b X q M 2 br + m 2 b + M2 Z c 2βQ b s 2 W m b1,m b2,θ b with X q = A q µ κ, κ = {cotβ, tan β} for q = t,b, tan β v u /v d Off-diagonal element is prop. to mass of partner quark mixing important in t sector, for large tan β also in b, τ sect. Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.21

34 Squark and slepton mixing ( M 2 t M t = + m 2 L t + M2 Z c 2β(Tt 3 Q ts 2 W) m t X q m t X q M 2 t R + m 2 t + M2 Z c 2βQ t s 2 W ) m t 1,m t 2,θ t M b = ( M + m 2 bl 2 b + M2 Z c 2β(Tb 3 Q bs 2 W) m b Xq ) m b X q M 2 br + m 2 b + M2 Z c 2βQ b s 2 W m b1,m b2,θ b with X q = A q µ κ, κ = {cotβ, tan β} for q = t,b, tan β v u /v d Gauge invariance M t L = M bl relation between m t 1,m t 2,θ t,m b1,m b2,θ b Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.22

35 Mass relations in the MSSM SM: all masses are free input parameters (except M W -M Z rel.) MSSM: Sfermion mass relations, e.g. m 2 ẽ L = m 2 ν L M 2 W cos(2β) Relations between neutralino and chargino masses Upper bound on mass of lightest CP-even Higgs boson Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.23

36 Mass relations in the MSSM SM: all masses are free input parameters (except M W -M Z rel.) MSSM: Sfermion mass relations, e.g. m 2 ẽ L = m 2 ν L M 2 W cos(2β) Relations between neutralino and chargino masses Upper bound on mass of lightest CP-even Higgs boson All relations receive corrections from loop effects effects of soft SUSY breaking, ew symmetry breaking Experimental verification of parameter relations is a crucial test of SUSY! Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.23

37 The Higgs sector of the MSSM Simplest extension of the minimal Higgs sector: Minimal Supersymmetric Standard Model (MSSM) Two doublets to give masses to up-type and down-type fermions (extra symmetry forbids to use same doublet for both) Supersymmetry imposes relations between the parameters Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.24

38 The Higgs sector of the MSSM Simplest extension of the minimal Higgs sector: Minimal Supersymmetric Standard Model (MSSM) Two doublets to give masses to up-type and down-type fermions (extra symmetry forbids to use same doublet for both) Supersymmetry imposes relations between the parameters Two parameters instead of one: tan β v u v d, M A (or M H ±) Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.24

39 Higgs potential of the MSSM MSSM Higgs potential contains two Higgs doublets: V = m 2 1H 1 H1 + m 2 2H 2 H2 m 2 12(ǫ ab H a 1H b 2 + h.c.) + g 2 + g 2 8 }{{} (H 1 H1 H 2 H2 ) 2 + g2 2 }{{} H 1 H2 2 Five physical states: h 0,H 0,A 0,H ± Input parameters: tanβ v 2 v 1, M A gauge couplings, in contrast to SM M h, M H, mixing angle α, M H ±: derived quantities Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.25

40 Higgs mass bound in the MSSM: Prediction for M h, M H,... Tree-level result for M h, M H : MH,h 2 = 1 [ MA 2 + MZ 2 ± (MA M2 Z )2 4MZ 2M2 A cos2 2β ] M h M Z at tree level MSSM tree-level bound (gauge sector): excluded by LEP! Large radiative corrections (Yukawa sector,... ): Yukawa couplings: e m t 2M W s W, e m 2 t M W s W,... Dominant one-loop corrections: G µ m 4 t ln ( m t 1 m t 2 m 2 t ), O(100%)! Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.26

41 Higgs mass bound in the MSSM: Present status of M h prediction in the MSSM: Complete one-loop + almost complete two-loop result available Upper bound on M h (FeynHiggs): [S. Heinemeyer, W. Hollik, G. W. 99], [M. Frank, S. Heinemeyer, W. Hollik, G. W. 02] [G. Degrassi, S. Heinemeyer, W. Hollik, P. Slavich, G. W. 02] M h < 135 GeV Extensions of the MSSM: M h < 200 GeV (if couplings stay perturbative up to high scale) SUSY requires a light Higgs boson Definite and robust prediction, testable at LHC and ILC Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.27

42 SUSY searches at the LHC Dominated by production of coloured superpartners: gluino, squarks Very large mass reach in the searches for jets + missing energy gluino, squarks accessible up to 2 3 TeV very good prospects for discovering SUSY particles if low-energy SUSY is realised in nature Access to uncoloured superpartners (usually lighter than coloured ones) mainly via cascade decays of squarks, gluino Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.28

43 SUSY production cross sections at the LHC 10 3 Prospino2 (T Plehn) σ tot [pb]: pp g g, q q, t 1t 1, χ 2 o χ 1+, ν ν, χ 2o g, χ 2o q 10 2 t 1t 1 g g 10 q q χ 2o χ 1+ ν ν χ 2o q χ 2o g S = 14 TeV NLO LO m [GeV] Squark and gluino couplings α s Cross sections mainly determined by m q, g, small residual model dependence σ 50 pb for m q, g = 500 GeV, σ 1 pb for m q, g = 1 TeV Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.29

44 LHC discovery reach in m 0 m 1/2 plane of the CMSSM for jets + miss. energy, 1 fb 1 and 10 fb 1 [CMS 06] Large coverage even with 1 fb 1 of understood data [see G. Polesello s talk] Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.30

45 What is the scale of Supersymmetry? Electroweak precision physics sensitivity to loop effects Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.31

46 What is the scale of Supersymmetry? Electroweak precision physics sensitivity to loop effects Example: indirect constraints on M H in the SM Theory uncertainty α had = α (5) ± ± incl. low Q 2 data m Limit = 144 GeV [LEPEWWG 07] χ Excluded Preliminary m H [GeV] Tension between indirect bounds on M H in the SM and direct search limit has increased Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.31

47 Prediction for M W (parameter scan): SM vs. MSSM Prediction for M W in the SM and the MSSM: M W [GeV] M H = 114 GeV SM M H = 400 GeV light SUSY SM MSSM both models MSSM heavy SUSY Heinemeyer, Hollik, Stockinger, Weber, Weiglein 07 [S. Heinemeyer, W. Hollik, A.M. Weber, G. W. 07] MSSM: SUSY parameters varied SM: M H varied m t [GeV] Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.32

48 Prediction for M W (parameter scan): SM vs. MSSM Prediction for M W in the SM and the MSSM: experimental errors 68% CL: LEP2/Tevatron (today) M W [GeV] M H = 114 GeV SM M H = 400 GeV light SUSY SM MSSM both models MSSM heavy SUSY Heinemeyer, Hollik, Stockinger, Weber, Weiglein 07 [S. Heinemeyer, W. Hollik, A.M. Weber, G. W. 07] MSSM: SUSY parameters varied SM: M H varied m t [GeV] Slight preference for MSSM over SM Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.33

49 Prediction for M W (parameter scan): SM vs. MSSM Prediction for M W in the SM and the MSSM: experimental errors 68% CL: LEP2/Tevatron (today) M W [GeV] M H = 114 GeV SM Tevatron/LHC ILC/GigaZ M H = 400 GeV light SUSY SM MSSM both models MSSM heavy SUSY Heinemeyer, Hollik, Stockinger, Weber, Weiglein 07 [S. Heinemeyer, W. Hollik, A.M. Weber, G. W. 07] MSSM: SUSY parameters varied SM: M H varied m t [GeV] Slight preference for MSSM over SM Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.34

50 Sensitivity to the scale of Supersymmetry CMSSM with restrictions from dark matter relic density: m 1/2, m 0, A 0 (GUT scale), tan β, sign(µ) (weak scale) Low-energy spectrum from renormalisation group running Cold dark matter (CDM) density (WMAP,... ): < Ω CDM h 2 < Constraints on SUSY parameter space χ 2 fit in the CMSSM with dark matter constraints Electroweak precision observables (EWPO): M W, sin 2 θ eff, Γ Z, (g 2) µ, M h B-physics observables (BPO): BR(b sγ), BR(B s µ + µ ), BR(B u τν τ ), M Bs Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.35

51 χ 2 fit in the CMSSM, EWPO + BPO: M W, sin 2 θ eff, Γ Z, (g 2) µ, M h, BR(b sγ), BR(B s µ + µ ), BR(B u τν τ ), M Bs [J. Ellis, S. Heinemeyer, K. Olive, A. Weber, G. W. 07] tan β = 10: tan β = 50: χ 2 (today) 8 6 CMSSM, µ > 0, m t = GeV χ 2 (today) 8 6 CMSSM, µ > 0, m t = GeV tanβ = 10, A 0 = 0 tanβ = 50, A 0 = 0 4 tanβ = 10, A 0 = +m 1/2 4 tanβ = 50, A 0 = +m 1/2 tanβ = 10, A 0 = -m 1/2 tanβ = 50, A 0 = -m 1/2 2 tanβ = 10, A 0 = +2 m 1/2 2 tanβ = 50, A 0 = +2 m 1/2 0 tanβ = 10, A 0 = -2 m 1/ m 1/2 [GeV] 0 tanβ = 50, A 0 = -2 m 1/ m 1/2 [GeV] Good description of the data Preference for relatively light SUSY scale Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.36

52 Fit results for particle masses, tan β = 10: m χ + 1 m χ 0 2, m τ1 [J. Ellis, S. Heinemeyer, K. Olive, A. Weber, G. W. 07] χ 2 (today) 8 6 CMSSM, µ > 0, m t = tanβ = 10, A 0 = 0 χ 2 (today) 8 6 CMSSM, µ > 0, m t = tanβ = 10, A 0 = 0 4 tanβ = 10, A 0 = +m 1/2 4 tanβ = 10, A 0 = +m 1/2 tanβ = 10, A 0 = -m 1/2 tanβ = 10, A 0 = -m 1/2 2 tanβ = 10, A 0 = +2 m 1/2 2 tanβ = 10, A 0 = +2 m 1/2 tanβ = 10, A 0 = -2 m 1/ m χ ~0, m 2 χ ~+ [GeV] 1 tanβ = 10, A 0 = -2 m 1/ m~ τ [GeV] 1 Good prospects for the LHC and ILC Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.37

53 Global CMSSM fit, all CMSSM parameters and dark matter constraint included in the fit 68% (dotted) and 95% (solid) confidence level regions [O. Buchmueller, R. Cavanaugh, A. De Roeck, S. Heinemeyer, G. Isidori, P. Paradisi, F. Ronga, A. Weber, G. W. 07] 1000 A m 1/2 Best fit values: tan β 10, m 1/2 300 GeV Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.38

54 Indirect limits on the light Higgs mass in the CMSSM EWPO + BPO + dark matter constraints χ 2 fit for M h, without imposing direct search limit [O. Buchmueller, R. Cavanaugh, A. De Roeck, S. Heinemeyer, G. Isidori, P. Paradisi, F. Ronga, A. Weber, G. W. 07] 2 χ 4 SM CMSSM 3.5 arxiv: LEP excluded [GeV] High sensitivity, less tension than in SM m H Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.39

55 Comparison of preferred region in m 0 m 1/2 plane with LHC discovery reach for 1 fb 1 [O. Buchmueller, R. Cavanaugh, A. De Roeck, S. Heinemeyer, G. Isidori, P. Paradisi, F. Ronga, A. Weber, G. W. 07] Preferred region would lead to early discovery Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.40

56 SUSY Higgs physics at the LHC MSSM Higgs sector: simplest extension of SM Higgs sector, two parameters instead of one Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.41

57 SUSY Higgs physics at the LHC MSSM Higgs sector: simplest extension of SM Higgs sector, two parameters instead of one Many theories have over large part of their parameter space a light Higgs with properties very similar to those of the SM Higgs boson Example: SUSY in the decoupling limit, M A M Z Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.41

58 SUSY Higgs physics at the LHC MSSM Higgs sector: simplest extension of SM Higgs sector, two parameters instead of one Many theories have over large part of their parameter space a light Higgs with properties very similar to those of the SM Higgs boson Example: SUSY in the decoupling limit, M A M Z How can one distinguish the SM-like state from the SM-Higgs? How can one detect / identify the other states? Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.41

59 MSSM Higgs discovery contours (m max h scenario) tanβ h 0 H A H ATLAS ATLAS fb maximal mixing h 0 H A 0 0 h H h H 0 h only LEP 2000 LEP excluded 2 0 h 0 H A H 0 h H m A (GeV) Discovery of at least one Higgs state expected Significant region where only one SM-like Higgs can be detected at the LHC Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.42

60 Higgs couplings: sensitivity to deviations from the SM SM vs. BSM physics (ILC precisions): Precision measurement of Higgs couplings allows distinction between different models Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.43

61 Higgs coupling determination at the LHC LHC does not provide a measurement of the total production cross section (no recoil method like LEP, ILC: e + e ZH, Z e + e,µ + µ ) Production decay at the LHC yields combinations of Higgs couplings (Γ prod, decay g 2 prod, decay ): σ(h) BR(H a + b) Γ prodγ decay Γ tot, Large uncertainty on dominant decay for light Higgs: H b b LHC can directly determine only ratios of couplings, e.g. g 2 Hττ /g2 HWW Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.44

62 Higgs coupling determination at the LHC Absolute values of the couplings at the LHC can be obtained with an additional (mild) theory assumption: [M. Dührssen, S. Heinemeyer, H. Logan, D. Rainwater, G. W., D. Zeppenfeld 04] g 2 HV V (g2 HV V )SM, V = W,Z Upper bound on Γ V Observation of Higgs production Lower bound on production couplings and Γ tot Observation of H V V in WBF Determines Γ 2 V /Γ tot Upper bound on Γ tot Absolute determination of Γ tot and Higgs couplings Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.45

63 Access to the Hb b coupling via central exclusive diffractive (CED) Higgs production, pp p H p Protons remain undestroyed, forward proton tagging in roman pot detectors exchange of colour-singlet no hadronic activity between outgoing protons and Higgs decay products J z = 0 selection rule Good mass resolution, access to H b b decay mode Experimentally very challenging (pile-up, in particular at high lumi,... ), but may yield interesting information [see talks by A. Martin, M. Grothe, C. Royon] Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.46

64 3σ contours for CED production of the light MSSM Higgs boson in the h b b channel [S. Heinemeyer, V.A. Khoze, M.G. Ryskin, W.J. Stirling, M. Tasevsky, G. W. 07] tan β L = 60 fb -1 L = 60 fb, eff. 2-1 L = 600 fb -1 L = 600 fb, eff M h M h = 131 GeV = 130 GeV 10 5 M h = 115 GeV M h = 125 GeV [GeV] Almost complete coverage with high integrated luminosity CED channel may yield crucial information on hb b coupling Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.47 m A

65 5σ discovery contours for CED production of the heavy CP-even MSSM Higgs, H b b channel [S. Heinemeyer, V.A. Khoze, M.G. Ryskin, W.J. Stirling, M. Tasevsky, G. W. 07] tan β M H = 132 GeV = 140 GeV M H = 160 GeV M H = 200 GeV M H = 245 GeV M H L = 60 fb, eff. 2-1 L = 600 fb -1 L = 600 fb, eff [GeV] Significant discovery reach, discovery of a 140 GeV Higgs for all values of tan β with high integrated luminosity Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.48 m A

66 "Typical" features of extended Higgs sectors A light Higgs with SM-like properties, couples with about SM-strength to gauge bosons Heavy Higgs states that decouple from the gauge bosons For non-standard Higgs states: Cannot use weak-boson fusion channels for production Possible production channels: gg H, b bh,... Cannot use LHC gold plated decay mode H ZZ 4µ Search for heavy Higgs bosons H,A,H ± is very different from the SM case Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.49

67 We cannot take a SM-type Higgs for granted Higgs phenomenology can be drastically different from the SM case even in the MSSM: Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.50

68 We cannot take a SM-type Higgs for granted Higgs phenomenology can be drastically different from the SM case even in the MSSM: Higgs may be much lighter than 114 GeV Example: SUSY with CP-violation no firm experimental lower bound on M H LHC needs to look also for light Higgs bosons Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.50

69 We cannot take a SM-type Higgs for granted Higgs phenomenology can be drastically different from the SM case even in the MSSM: Higgs may be much lighter than 114 GeV Example: SUSY with CP-violation no firm experimental lower bound on M H LHC needs to look also for light Higgs bosons Significant suppression / enhancement of various couplings possible with respect to the SM Example: large enhancement of H bb coupling large suppression of BR(h γγ), BR(h WW ),... Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.50

70 We cannot take a SM-type Higgs for granted Higgs decays into SUSY particles, H invisible, H soft jets,... SUSY decays into Higgs,... Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.51

71 We cannot take a SM-type Higgs for granted Higgs decays into SUSY particles, H invisible, H soft jets,... SUSY decays into Higgs,... NMSSM: h aa, singlet dominated light Higgs,... More exotic scenarios: Higgs radion mixing, continuum Higgs models,... Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.51

72 We cannot take a SM-type Higgs for granted Higgs decays into SUSY particles, H invisible, H soft jets,... SUSY decays into Higgs,... NMSSM: h aa, singlet dominated light Higgs,... More exotic scenarios: Higgs radion mixing, continuum Higgs models,... Need to be prepared for non-standard phenomenology Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.51

73 SUSY processes at the LHC LHC: scattering of composite objects, strongly interacting Very large QCD backgrounds, low signal to background ratios Signal cross sections for SM QCD, SUSY, Higgs,... [see talks by S. Moch, R. Cousins] Search for SUSY, Higgs,... at the LHC: Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.52

74 SUSY processes at the LHC LHC: scattering of composite objects, strongly interacting Very large QCD backgrounds, low signal to background ratios Signal cross sections for SM QCD, SUSY, Higgs,... [see talks by S. Moch, R. Cousins] Search for SUSY, Higgs,... at the LHC: Like the search for a needle in 100,000 haystacks [J. Ellis, SUSY07] Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.52

75 SM backgrounds to missing energy signals [M. Mangano, SUSY07] Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.53

76 Instrumental backgrounds [see R. Cousins talk] [M. Mangano, SUSY07] Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.54

77 Determining backgrounds from data [M. Mangano, SUSY07] Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.55

78 Role of theoretical predictions [M. Mangano, SUSY07] Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.56

79 SUSY signals at the LHC LHC: good prospects for strongly interacting new particles long decay chains complicated final states e.g.: g q q qq χ 0 2 qq ττ qqττ χ 0 1 Many states are produced at once, difficult to disentangle Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.57

80 SUSY signals at the LHC LHC: good prospects for strongly interacting new particles long decay chains complicated final states e.g.: g q q qq χ 0 2 qq ττ qqττ χ 0 1 Many states are produced at once, difficult to disentangle It quacks like SUSY! Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.57

81 SUSY signals at the LHC LHC: good prospects for strongly interacting new particles long decay chains complicated final states e.g.: g q q qq χ 0 2 qq ττ qqττ χ 0 1 Many states are produced at once, difficult to disentangle It quacks like SUSY! But ist it really SUSY? Which particles are actually produced? Main background for determining SUSY properties at the LHC will be SUSY itself! Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.57

82 It quacks like SUSY, but... Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.58

83 It quacks like SUSY, but... does every SM particle really have a superpartner? do their spins differ by 1/2? are their gauge quantum numbers the same? are their couplings identical? do the SUSY predictions for mass relations hold,...? Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.58

84 Even when we are sure that it is actually SUSY, we will still want to know: Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.59

85 Even when we are sure that it is actually SUSY, we will still want to know: is the lightest SUSY particle really the neutralino, or the stau or the sneutrino, or the gravitino or...? is it the MSSM, or the NMSSM, or the mnssm, or the N 2 MSSM, or...? what are the experimental values of the 105 (or more) SUSY parameters? does SUSY give the right amount of dark matter? what is the mechanism of SUSY breaking? We will ask similar questions for other kinds of new physics Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.59

86 SUSY searches at the LHC Cascade decays: complicated decay chains for squarks and gluinos q q L χ 0 2 R χ Main tool: dilepton edge from χ 0 2 l + l χ m(ll) (GeV) Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.60

87 Information from kinematical edges and `m2 ll edge = thresholds `m2 χ 0 m 2 lr m 2 `m2 lr 2 χ 0 1 m 2 lr `m2 qll edge = `m2 ql m 2 χ 0 2 `m2 χ 0 m 2 χ `m2 ql edge min = `m2 ql edge max = `m2 ql m 2 χ 0 2 m 2 χ 0 2 `m2 χ 0 2 m 2 χ 0 2 m 2 lr `m2 ql m 2 χ 0 2 `m2 lr m 2 χ 0 1 m 2 lr `m2 qll thres = [(m 2 ql + m 2 χ 0 2)(m 2 χ 0 m 2 lr )(m 2 lr m 2 χ 2 0 ) 1 r (m 2 q L m 2 χ 0 (m 2) 2 χ 0 + m 2 lr ) 2 (m 2 lr + m 2 χ 2 0 ) 2 16m 2 χ 1 0 m 4 lr m 2 χ m 2 lr (m 2 q L m 2 χ 0 )(m 2 χ m 2 χ 0 )]/(4m 2 lr m 2 χ 1 0 2) Precise information on mass squared differences From overconstrained system absolute mass determination Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.61

88 Dilepton edges Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.62

89 Dilepton edges Experimentalist s definition of a lepton: e ±, µ ± τ s are much more challenging Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.62

90 Dilepton edges Experimentalist s definition of a lepton: e ±, µ ± τ s are much more challenging However, most of the leptons are in fact τ s, completely dominate at high tan β E.g.: SPS1a, tanβ = 10: BR( χ 0 2 ẽ± e ) = BR( χ 0 2 µ± µ ) = 6% BR( χ 0 2 τ ± τ ) = 88% Use more information than just the kinematic edges: complete shapes? Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.62

91 Dilepton edges Experimentalist s definition of a lepton: e ±, µ ± τ s are much more challenging However, most of the leptons are in fact τ s, completely dominate at high tan β E.g.: SPS1a, tanβ = 10: BR( χ 0 2 ẽ± e ) = BR( χ 0 2 µ± µ ) = 6% BR( χ 0 2 τ ± τ ) = 88% Use more information than just the kinematic edges: complete shapes? What is the impact of Monte Carlo uncertainties, higher-order contributions? Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.62

92 Particle spins and CP properties Determination of spin and CP prop. of observed new states will be crucial for establishing the SUSY nature of the signal Spin: establish fermion boson symmetry, distinguish from universal extra dimensions (can have similar spectrum as in SUSY, but different spins), spin 2 excitations,... CP properties: pseudo-scalar Higgs, mixed states,... CP violation: Measure CPV effects in CP-conserving observables? Access to CP-violating observables: CP asymmetries, triple products,...? Very important information, but experimentally challenging at the LHC [see G. Polesello s talk] Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.63

93 SUSY parameter determination Need a comprehensive and precise determination of as many SUSY parameters as possible in order to establish SUSY experimentally disentangle patterns of SUSY breaking Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.64

94 SUSY parameter determination Need a comprehensive and precise determination of as many SUSY parameters as possible in order to establish SUSY experimentally disentangle patterns of SUSY breaking SUSY contains many parameters that are not closely related to a specific experimental observable: mixing angles, tan β, complex phases,... Most observables depend on a variety of SUSY parameters SUSY parameters need to be determined by global fits to a large set of observables Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.64

95 SUSY parameter determination Need a comprehensive and precise determination of as many SUSY parameters as possible in order to establish SUSY experimentally disentangle patterns of SUSY breaking SUSY contains many parameters that are not closely related to a specific experimental observable: mixing angles, tan β, complex phases,... Most observables depend on a variety of SUSY parameters SUSY parameters need to be determined by global fits to a large set of observables How well can we identify particles in different decay chains? Theory uncertainties? Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.64

96 How precisely do we need to know the SUSY parameters? Dark matter relic density: measurement vs. prediction Aim: match the precision of the relic density measurement with the prediction based on collider data sensitive test of SUSY dark matter hypothesis Relic density measurement: current (WMAP): 10% future (Planck): 2% Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.65

97 Prediction of the dark matter density We cannot assume a certain SUSY scenario (CMSSM), we have to test it Need precision measurements of: Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.66

98 Prediction of the dark matter density We cannot assume a certain SUSY scenario (CMSSM), we have to test it Need precision measurements of: LSP mass the dark matter particle Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.66

99 Prediction of the dark matter density We cannot assume a certain SUSY scenario (CMSSM), we have to test it Need precision measurements of: LSP mass the dark matter particle LSP couplings Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.66

100 Prediction of the dark matter density We cannot assume a certain SUSY scenario (CMSSM), we have to test it Need precision measurements of: LSP mass the dark matter particle LSP couplings NLSP LSP mass difference ( coannihilation region ), down to 0.2 GeV Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.66

101 Prediction of the dark matter density We cannot assume a certain SUSY scenario (CMSSM), we have to test it Need precision measurements of: LSP mass the dark matter particle LSP couplings NLSP LSP mass difference ( coannihilation region ), down to 0.2 GeV Higgs masses, Higgs couplings ( Higgs funnel region ) Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.66

102 Prediction of the dark matter density We cannot assume a certain SUSY scenario (CMSSM), we have to test it Need precision measurements of: LSP mass the dark matter particle LSP couplings NLSP LSP mass difference ( coannihilation region ), down to 0.2 GeV Higgs masses, Higgs couplings ( Higgs funnel region ) Prediction for focus point region depends extremely sensitively on m t through RGE running: would need m t with accuracy of O(20 MeV)... [see M. Drees talk] Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.66

103 Determination of SUSY parameters: global fit Comparison: LHC only vs. LHC ILC for SPS1a point m 0 = 100 GeV, m 1/2 = 250 GeV, A 0 = 100 GeV, tan β = 10, µ > 0 bulk region of msugra scenario best case scenario [P. Bechtle, K. Desch, P. Wienemann 05] LHC input: mass measurements and precisions from detailed experimental studies at ATLAS and CMS + assumption on t 1,2 mass measurement + ratios of Higgs branching ratios Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.67

104 Fittino: LHC only vs. LHC ILC Parameter True value ILC Fit value Uncertainty Uncertainty (ILC+LHC) (LHC only) tan β µ GeV GeV 1.2 GeV 811. GeV X τ GeV GeV 20.GeV GeV MẽR GeV GeV 0.27 GeV 39. GeV M τr GeV GeV 0.41 GeV GeV MẽL GeV GeV 0.10 GeV 12.9 GeV M τl GeV GeV 0.14 GeV GeV X t GeV GeV 3.1 GeV 548. GeV X b GeV GeV GeV GeV MũR 503. GeV 503. GeV 24. GeV 25. GeV M br 497. GeV 497. GeV 8. GeV GeV M t R GeV GeV 2.5 GeV 753. GeV MũL 523. GeV 523. GeV 10. GeV 19. GeV M t L GeV GeV 3.1 GeV 424. GeV M GeV GeV 0.06 GeV 8.0 GeV M GeV GeV 0.10 GeV 132. GeV M GeV 569. GeV 7. GeV 10.1 GeV m A run GeV GeV 4.6 GeV GeV m t GeV GeV GeV 0.27 GeV χ 2 for unsmeared observables: most of the Lagrangian parameters can hardly be constrained by LHC data alone (even for SPS1a) need LHC ILC for determination of SUSY parameters [see K. Desch s talk] Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.68

105 Conclusions LHC will open the new territory of TeV-scale physics, where we firmly expect ground-breaking discoveries Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.69

106 Conclusions LHC will open the new territory of TeV-scale physics, where we firmly expect ground-breaking discoveries SUSY can show up in many different ways: we have to be prepared for a wide range of possible phenomenology Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.69

107 Conclusions LHC will open the new territory of TeV-scale physics, where we firmly expect ground-breaking discoveries SUSY can show up in many different ways: we have to be prepared for a wide range of possible phenomenology Detection of a BSM signal will only be a first step Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.69

108 Conclusions LHC will open the new territory of TeV-scale physics, where we firmly expect ground-breaking discoveries SUSY can show up in many different ways: we have to be prepared for a wide range of possible phenomenology Detection of a BSM signal will only be a first step Large experimental efforts + accurate theory predictions will be necessary to determine the nature of TeV-scale physics Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.69

109 Conclusions LHC will open the new territory of TeV-scale physics, where we firmly expect ground-breaking discoveries SUSY can show up in many different ways: we have to be prepared for a wide range of possible phenomenology Detection of a BSM signal will only be a first step Large experimental efforts + accurate theory predictions will be necessary to determine the nature of TeV-scale physics Looking forward to very exciting times! Supersymmetry at the LHC, Georg Weiglein, Heidelberg 08/2007 p.69