BSM at the LHC. Dirk Zerwas LAL Orsay

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1 BSM at the LHC Dirk Zerwas LAL Orsay Lecture I: LHC and the Detectors Standard Model Lecture II: The standard model Higgs boson The supersymmetric Higgs bosons Lecture III: Supersymmetry Exotics

2 Supersymmetry Fermion Boson has no problems with radiative corrections (quadrat. Div.) has a light Higgs boson (<135GeV) promises exciting phenomenology at the TeV scale 3 neutral Higgs bosons: h, A, H 1 charged Higgs boson: H ± and supersymmetric particles: spin-0 Squarks: q ~ R, ~ q L Sleptonen: ~ ~ l R, l L h,h,a H ± spin-1/2 q Gluino: g~ l Neutralino χ i=1-4 Charginos: χ ± i=1-2 spin-1 g Z, γ W ± The parameters of the Higgs sector: m A : mass dof the pseudoscalar Higgs Boson tanβ: ratio of the vacuum expectation values mass of the top quarks ~ ~ stop (t R, t L ) sector: masses and mixing Many different models: MSSM (minimal supersymmetric extension of the SM, parameter EW Scale) msugra (minimal supergravity, GUT Scale) GMSB AMB NMSSM Conservation of R-parity production of SUSY particles in pairs (Cascade-) decays to the lightest SUSY particle LSP stable, neutral and weakly interacting: Neutralino (χ 1 ) experimental signature: missing E T

3 Unification of coupling constants Allanach et al, hep-ph/ Supersymmetry Supersymmetrie breaking: msugra: 5 parameters GUT scale MSSM: 24 parameters electroweak Scale ES-Skala 10 2 GeV GUT GeV LEP: m H >114GeV Electroweak Fit: m H <144GeV (top mass, W-mass, sin 2 θ W.) LEP: M(sparticles) > GeV Low tanβ excluded by Higgs search TeVatron: M(squarks,gluinos) > 400GeV

4 SPS1a typical example of a supersymmetric spectrum m 0 = 100GeV m 1/2 = 250GeV A 0 = -100GeV tanβ =10 sign(μ)=+ favourable for LHC and ILC (Complementarity) Moderately heavy gluinos and squarks Physics Interplay of the LHC and ILC Editor G. Weiglein hep-ph/ Heavy and light gauginos Higgs at the limit of LEP reach light sleptons τ~ 1 lighter than lightest χ ± : χ ± BR 100% τν ~ χ 2 BR 90% ττ ~ cascade: q ~ ~ L χ 2 q l R l q llqχ 1 visible

5 Supersymmetry: Higgs and SUSY Higgs bosons invisible (=neutralinos) ZH ll+inv Analysis: 2l, Etmiss, jet-veto, b-jet veto Background: tt, ZZ, WZ, ZZ+jets Higgs bosons in SUSY cascades Signal to noise ratio: OK (better than SM ) But very model dependent BRinvisible excluded VBF: best channel, but: trigger?

6 Supersymmetry: Squarks and Gluinos Signature: multi-jet with missing E T effective mass Missing E T SM SUSY SM background also has jets. The old plot

7 Cross sections Supersymmetry: Squarks and Gluinos Cross sections large: easy discovery in inclusive channels 10fb-1 ~ 2TeV Similar approach for l+jets

8 Supersymmetry Electroweak Production: χ 0 2 χ± 1 lνχllχ (l=e,μ) Background: Drell-Yan, Z+Jets,tt, WZ Focus Point: m 0 =3500GeV m 1/2 =300GeV tanβ=10 A0=0 Search for Gluinos gluino tbχ,ttχ Untergrund: tt S/sqrt(B) ~ 7 gluino ttχ 10fb-1

9 Supersymmetry: Masses Long cascades Jet-Lepton, lepton-lepton, lepton-lepton-jet are functions of the masses Analysis: at least 4 jets PT1>150GeV, 100GeV, 50GeV Meff>600GeV, Etmiss<max(100,20%Meff) Leptons: 2 opposite sign same flavour (OSSF) (ee, μμ) background subtraction (SUSY) with OSOF (eμ) tutorial for the proof.

10 Supersymmetry: Masses Mass determination for 300fb -1 (thus 2014) LHC: Toy MC from edges, thresholds to masses Next: Selected m ll near edge: χ at rest P(χ 2 ) = (1-m(χ 1 ) /m ll ) P(ll) 2b-tagged jets m(χbb) versus m(χb) (2 entries per event) Select m(χbb) < m(χb) + 150GeV

11 Supersymmetry: Masses Next determine the gluino mass: 380GeV<m χb < 600GeV M χbb is then the gluino mass Next get the sbottom mass(es): Background small Dominant error: energy scale Difficult to extract the two masses

12 Supersymmetry: Masses and spin Neutralino2 to stau: Stau decays to tau reconstruction 50% efficient (hadronic channel) Jet-rejection: 1/100 endpoint sensitive to stau mass (same as ll edge) events in edge used to measure branching ratio of slepton to stau? Many open questions: spin (long decay lq mass?) number of sparticles completeness of spectrum majorana nature of gluinos is all of this generalizable?

13 Masses: The final word 2m μ ~ Masses: threshold cross section measurement Polesello et al: use of χ 1 from ILC (high precision) in LHC analyses improves the mass determination

14 Determining the underlying parameters Transform (s)particle properties to fundamental parameters: msugra (top-down) and MSSM (bottom-up) with conservation of R-parity Beenakker et al need predictions for all observables matching theoretical and experimental precision observables sensitive to several parameters: correlations, error propagation Brain power and sophisticated tools: Mass spectra generated by SOFTSUSY, SUSPECT, SPHENO Branching ratios by MSMLIB, SPHENO, SDecay e+e- cross sections (polarized) by SPHENO NLO proton cross sections by Prospino2.0 Putting it all together (error propagation, search for minima etc): FITTINO and SFITTER P. Skands et al., SUSY Les Houches accord (SLHA), Interfacing SUSY spectrum calculators, decay packages, and event generators, JHEP 0407 (2004) 036

15 Information Extraction from Standard Measurements alone Buchmueller et al: electroweak plus dark matter, b sγ, b μμ CMSSM χ 2 slightly better than SM m h = ±3GeV Allanach et al: Predict SUSY cross sections at LHC: ~fb μ and B (high scale parameters) Bayesian measure: same order of magnitude for all parameters (no scale imposed nor unification) slightly higher cross sections in non-bayesian approach (Profile Likelihood ~maximum instead of measure)

16 scale: msugra Hypothesis: SUSY particles discovered and discrete quantum numbers (spin) measured msugra advantage: few parameters, testing ground for studies of principles disadvantage: starts at GUT scale and adds RGE extrapolation, not the most general lagrangian brute force method MINUIT: disadvantage: starting point First question: do we find the right point? brute force method GRID: disadvantage: N P advantage: computer industry (OECD?) m 0 m 1/2 tanβ A0 SPS1a Start 1TeV 1TeV 50 0GeV Sign(μ) fixed ~300 toy experiments: convergence OK with MINUIT alone for LHC (largest errors)!

17 Fittino: Simulated annealing scale: msugra SFitter: Markov Chains (efficient sampling in high dimensions, linear in number of parameters) Full dimensional exclusive likelihood map with the possibility of different types of projections: marginalisation (Bayes) introduces a measure profile likelihood (Frequentist approach) Ranked list of minima: secondary minima exist (LHC) discarded by χ 2 alone interplay with top mass (parameter!)

18 msugra: Errors RFit Scheme: Höcker, Lacker, Laplace, Lediberder No information within theory errors: flat distribution Higgs sleptons squarks,gluinos neutralinos, charginos 3GeV 1% 3% 1% use edges not masses (improvement: 10x)! e-scale correlations at LHC 25-50% impact on error remember the standard model (top quark mass 1GeV at LHC) 10%.

19 msugra: Errors LHC and ILC ILC improves by 3-4x on LHC LHC+ILC better than any machine alone Fittino: the beginning 1 fb -1 1 year low lumi 10 fb-1 3 years nominal 300 fb-1 and then the ILC: SFitter theory errors impact the expected precision at all machines also at LHC SPA project: precision of the theoretical calculations Eur.Phys.J.C46:43-60,2006

20 MSSM 19 parameters at the EW scale no unification of the 1 st and 2 nd generation mix techniques: markov flat full Parameter space MINUIT in 5 best points Markov flat gaugino-higgsino space MINUIT on 15 best points BW pdf on remaining parameters MINUIT on 5 best solutions (all parameters) 3 neutralino masses at LHC M1, M2, μ 8 fold ambiguity in Gaugino- Higgsino subspace at the LHC! LHC+ILC: all parameters determined several parameters improved

21 MSSM Running up to the GUT scale: G. Blair, W. Porod and P.M. Zerwas (Eur.Phys.J.C27: ,2003) P. Bechtle, K. Desch, P. Wienemann with W. Porod (Eur.Phys.J.C46: ,2006) SPS1a (SPA1): dashed bands: today s theory errors included unification measured from low energy (TeV) data from LHC+ILC remember: all results valid within a well defined model/hypothesis

22 Connection Colliders-Cosmology E. Baltz,M.Battaglia, M.Peskin, T.Wizansky: Phys.Rev.D74:103521,2006 Nojiri et al/dutta et al SUSY breaking parameters (determined) spectrum and couplings (deduced) darksusy, isared or micromegas Ω CDM h 2 =n LSP *m LSP (relic density) NASA/WMAP science team SPS1a Temperature range: ±200μK MSUGRA SPS1a (central value irrelevant) LHC : Ωh 2 = ± LHC+ILC: Ωh 2 = ± % precision at LHC, permil LHC+ILC theory errors! Measurement of the fluctuations of the cosmic microwave background WMAP Ω CDM h 2 =0.127±0.01 (astro-ph/ ) Planck Ω CDM h 2 ~ 2% Comparable precision of CMB and Collider data possible

23 A difficult example: SUSY with heavy scalars Arkani-Hamed & Dimopoulos 2004 Giudice, Romanino 2004 Phenomenology: scalar Mass scale 10 4 to 16 GeV scalars are at M S fermions O(TeV) SM Higgs h effective theory below MS at MS matching with complete theory and standard RGE N. Bernal, A. Djouadi, P. Slavich JHEP 0707:016,2007 E. Turlay et al. (Proceedings BSM-SUSY les Houches 2007) DSS parameters: M S : decoupling scale, scalar masses m1/2: gaugino mass parameter μ: Higgs mass parameter At: trilinear coupling at MS tanβ: mixing angle between Higgs at MS ATLAS/CMS talks: Paul de Jong, Tapas Sarangi, Daniel Teyssier Parameter determination at LHC possible

24 Beyond the supersymmetric standard model Extended Symmetries, GUT Heavy charged leptons pp γ/z/z L + L -, L ± Zl ± Parameters : m(l), m(z ), BR(L lz) Background : tt, VV +jets Alexa fb fb -1

25 Heavy neutrinos in the LR model SU(2) L xsu(2) R xu(1) B-L SU(2) L xu(1) Y Right-handed fermions in doublets N=n R heavy Majorana pp W R lν,ln N lw ljj inv mass peak pp Z R ll,nn Ferrari 00 m(z )= 3 TeV M(N)= 1 TeV Parameters : m(v R ), m(n), k=g R /g L Background : tt, VV +jets heavy quarks (E 6 ) pp D D ; D dz, uw inv mass peak Parameters : m(d), quark mixing angles m(n) accessible Integrated Lumi m(z ) Mehdiyev 05

26 new gauge bosons At least Z, frequently W (if SU(2)) Production : Drell Yan Decay : Z l + l -, qq W lν, qq Parameters : boson mixing angles and/or coupling constant ratio Background : Drell Yan standard inv (transv.) mass peak (l) M(Z )= 1.5 TeV M(W )= 1 TeV M T = invariant mass calculated from transverse momenta

27 new scalar and /or vector bosons: Lepto-Quarks Groups SU(4), SU(5), SO(10) ; squarks (RpV); LQ lq νq 2 types of final states : 2l + jets, l + jets + missing E T Parameters : m(lq), Λ 2 eff= Λ 2 L (lq)+ Λ 2 R(lq)+ Λ 2 L(νq) λ 2 eff 300 fb -1 Belyaev 05 H T = scalar sum of p T new Higgs sector: doubly charged Higgs! q W + W + ++ Δ L q q l + l +

28 Compositeness q q* q QCD + contact interaction 4 fermions Parameters : compositeness scale L, (sign of the interference) excited fermions quarks q* qg, qγ, qz, q W leptons l* lγ, lz Final states llγ(γ), llj(j) Quark substructure? Jet inclusive cross section g g N / 45 GeV Λ= 3TeV 5TeV 10 TeV 15 TeV 20 TeV QCD (GeV) p T Difficulties: Jet definition, energy scale, QCD cross section, PDF,

29 Little Higgs Effective Model: treats the hierarchy problem enlarged symmetry, broken a large scale introduces a heavy top T (~1 TeV), heavy Higgs f (~10 TeV), heavy gauge bosons Z H,W H, A H (~1 TeV) Divergences cancel at first ordre Parameters : scale f, l 1 /l 2 (top Yukawa), v (Higgs coupling), q, q (gauge angles) Gaugesector[SU(2) U(1)] 2 standard Higgs q q Z H,W H Discovery Test of the model Z H l + l -, qq Z H Zh, W + W - W H l ν, qq W H W ± h, W ± Z

30 T Zt (25%), Wb (50%) ht (25%) 5σ signal for M(T) < 2000 GeV T Wb Azuelos 04 q W + φ ++ Φ ++ W + W +, W λν W + q Impossible to detect for the allowed parameters

31 Extra Dimensions String Theories : 10 (or 11) dimensions! Only route today to include quantified gravity Gravitation experimentally ok to ~0.2 mm Extra Dimensions compactified on circles of radius R G ~ R n G Newton M Pl2 ~ R n M 2+n D + graviton field periodical in the XD Kaluza Klein (KK) towers : M (k) ~k/r Some numbers : M D = 1 TeV, n = 2 R = 0.08 mm R -1 = ev LHC n = 4 R = 1600 fm R -1 = 120 kev Continuum of graviton states Gauge interactions verified up to ~1 fm gravity can propagate in the bulk (XD), SM particles on the 3D-brane ADD Models/ large XD

32 ADD : direct production of KK graviton ( k) ( k) qq gg, γ G ( k ) qg qg jets + ET, γ + E ( k ) gg gg T 100 fb -1 Parameters : M D, n Background : jet + Z νν, jet +W lν (l lost) Vacavant 01

33 ADD : virtual KK graviton exchange qq, gg γγ, ll, ( WW, t t...) Parameters : Cut at M S (=M D ) to avoid divergences G KK qq, gg f f, VV Excess in distribution of dilepton, diphoton invariant mass, etc Combination of ll and γγ for 100 fb -1 Sensitivity up to M S = 7.4 TeV Kabachenko 01

34 Suppose that the XD are small : ħc x 1 TeV -1 = fm << fm access to SM particles, in particular gauge bosons, in the bulk not excluded KK Excitations de KK of gauge bosons: (m (k) ) 2 = (m (0) ) 2 + k 2 M 2 C k 2 M 2 C excitations are more distant!! Indirect limits (EW contraints) from gauge coupling of gauge bosons R TeV TeV -1 : excitations de KK des bosons de jauge (Z KK,W KK ) Resonant production Z KK l + l - W KK lν Observable up to M C ~ 6 TeV Also g KK tt, bb Excess in the distribution p T of di-jets due to the Gluon excitations Observable up to M C ~ 15 TeV Azuelos 04 Balasz 02 4TeV

35 The Randall Sundrum (RS) family of models 1 XD left or warped because metric non factorisable 5D-space delimited by 2 branes: Standard Model and Planck 2 parameters : r, curbature k -1, distance between branes r c ~ 1/M pl Same procedure as XD plates : o first, only the graviton propagates in the XD o then models appear where all Standard Model fields are in the bulk Randall Sundrum : thin width resonance of the graviton Signals : (1) G e + e μ + μ γ γ W W Z Z tt,,,(,, ) ( ) c= k/m Pl Radion : scalar field f stabilizes the brane distance, f hh (thin width) Light b KK, final state with 4 W

36 Black holes at Colliders Objects confined in R<R S If impact parameter < R S, black hole production! Cross section ~ p R S M D ~ TeV, cross section ~ 100 pb (lumi fb-1)!!! Decay : democratic (non-republican) all particles produced, incl. Higgs black hole factory = Higgs factory H bb CMS m H =130GeV W/Z M(bb) Attention : approximations contentious theory errors ++ also in the decay

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