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Anticipating New Physics at the LHC LISHEP09 J Hewett, SLAC Why New Physics @ the Terascale? • Electroweak Symmetry breaks at energies ~ 1 TeV (SM Higgs or ???) • WW Scattering unitarized at energies ~ 1 TeV (SM Higgs or ???) • Gauge Hierarchy: Nature is fine-tuned or Higgs mass must be stabilized by New Physics ~ 1 TeV • Dark Matter: Weakly Interacting Massive Particle must have mass ~ 1 TeV to reproduce observed DM density All things point to the Terascale! A Cellar of New Ideas ’67 The Standard Model ’77 Vin de Technicolor ’70’s ’90’s Supersymmetry: MSSM SUSY Beyond MSSM a classic! aged to perfection better drink now mature, balanced, well developed - the Wino’s choice svinters blend CP Violating Higgs all upfront, no finish lacks symmetry ’98 Extra Dimensions bold, peppery, spicy uncertain terrior ’02 Little Higgs ’90’s ’03 ’03 ’04 ’05 Fat Higgs Higgsless Split Supersymmetry Twin Higgs complex structure young, still tannic needs to develop sleeper of the vintage what a surprise! finely-tuned double the taste J. Hewett Last Minute Model Building Anything Goes! • • • • • • • Non-Communtative Geometries Return of the 4th Generation Hidden Valleys Quirks – Macroscopic Strings Lee-Wick Field Theories Unparticle Physics ….. (We stilll have a bit more time) The Hierarchy Problem Energy (GeV) Planck GUT 10 Weak Quantum Corrections: Virtual Effects drag Weak Scale to MPl desert 1019 1016 LHC 3 mH2 ~ All of known physics 10-18 Solar System Gravity ~ MPl2 The Hierarchy Problem: Little Higgs Energy (GeV) 1019 1016 . . . LHC Planck GUT 106 105 104 New Physics! New Physics! New Physics! 10 Weak 3 All of known physics 10-18 Solar System Gravity Stacks of Little Hierarchies Simplest Model: The Littlest Higgs with 1 ~ 10 TeV 2 ~ 100 TeV 3 ~ 1000 TeV ….. 3-Scale Model ~ 10 TeV: New Strong Dynamics Global Symmetry f ~ /4 ~ TeV: v ~ f/4 ~ 100 GeV: Sample Spectrum Symmetires Broken Pseudo-Goldstone Scalars New Gauge Fields Signal @ LHC New Fermions Light Higgs SM vector bosons & fermions The Hierarchy Problem: Extra Dimensions Energy (GeV) Planck GUT Simplest Model: Large Extra Dimensions desert 1019 1016 LHC 10 3 Weak – Quantum Gravity = Fundamental scale in 4 + dimensions MPl2 = (Volume) MD2+ All of known physics Gravity propagates in D = 3+1 + dimensions 10-18 Solar System Gravity Arkani-Hamed, Dimopoulis, Dvali Kaluza-Klein Gravitons in a Detector Indirect Signature Missing Energy Signature pp g + Gn Events / 50 GeV / 100 fb-1 LHC 102 10 1 10-1 10-2 JLH Mee [GeV] Vacavant, Hinchliffe Signals for Gravitational Fixed Points Drell-Yan t= SM 1 0.5 D=3+4 M* = 4 TeV • Fixed point renders GR non-perturbatively renormalizable and asymptotically safe • Gravity runs such that it becomes weaker at higher energies • Collider signals if √s ~ MPl • Graviton Exchange Modified • Graviton Emission generally unaffected • Parameterize by form factor in coupling • Could reduce signal! JLH, Rizzo, arXiv:0707.3182 Litim, Pheln, arXiv:0707.3983 The Hierarchy Problem: Extra Dimensions Energy (GeV) Planck GUT desert 1019 1016 LHC Model II: Warped Extra Dimensions strong curvature 10 3 Weak wk = MPl e-kr All of known physics 10-18 Solar System Gravity Randall, Sundrum Kaluza-Klein Gravitons in a Detector: SM on the brane Number of Events in Drell-Yan For this same model embedded in a string theory: AdS5 x S Spin-2 resonances in Drell-Yan Davoudiasl, JLH, Rizzo Kaluza-Klein Modes in a Detector: SM off the brane Fermion wavefunctions in the bulk: decreased couplings to light fermions for gauge & graviton KK states gg gn tt gg Gn ZZ Lillie, Randall, Wang, hep-ph/0701164 Agashe, Davoudiasl, Perez, Soni hep-ph/0701186 Issue: Top Collimation g1 = 2 TeV gg gn tt g1 = 4 TeV Lillie, Randall, Wang, hep-ph/0701164 The Hierarchy Problem: Higgsless Energy (GeV) Planck GUT desert 1019 1016 LHC Warped Extra Dimensions strong curvature 10 3 Weak wk = MPl e-kr With NO Higgs boson! All of known physics 10-18 Solar System Gravity Csaki, Grojean,Murayama, Pilo, Terning Framework: EW Symmetry Broken by Boundary Conditions SU(2)L x SU(2)R x U(1)B-L in 5-d Warped bulk Planck brane TeV-brane SU(2)L x SU(2)R SU(2)R x U(1)B-L U(1)Y WR, ZR get Planck scale masses SU(2)D BC’s restricted by variation of the action at boundary SU(2) Custodial Symmetry is preserved! W, Z get TeV scale masses left massless! Unitarity in Gauge Boson Scattering: What do we do without a Higgs? Exchange gauge KK towers: Conditions on KK masses & couplings: Csaki etal, hep-ph/0305237 (g1111)2 = k (g11k)2 4(g1111)2 M12 = k (g11k)2 Mk2 Necessary, but not sufficient, to guarantee perturbative unitarity! Some tension with precision EW Production of Gauge KK States @ LHC gg, qq g1 dijets Davoudiasl, JLH, Lilllie, Rizzo Balyaev, Christensen The Hierarchy Problem: Who Cares!! Planck Scale Gauge Hierarchy Problem Weak Scale Cosmological Constant Problem Cosmological Scale We have much bigger Problems! Split Supersymmetry: Energy (GeV) Arkani-Hamed, Dimopoulis hep-ph/0405159 Giudice, Romanino hep-ph/0406088 MGUT ~ 1016 GeV MS : SUSY broken at high scale ~ 109-13 GeV Scalars receive mass @ high scale Mweak 1 light Higgs + Fermions protected by chiral symmetry Collider Phenomenology: Gluinos • • • • • Pair produced via strong interactions as usual Gluinos are long-lived No MET signature Form R hadrons Monojet signature from gluon bremstrahlung q Gluino pair + jet cross section 1 0 ~ ~ g q q 100 fb-1 Rate ~ 0, due to heavy squark masses! JLH, Lillie, Masip, Rizzo hep-ph/0408248 The Hierarchy Problem: Supersymmetry Energy (GeV) Planck GUT Quantum Corrections: Virtual Effects drag Weak Scale to MPl desert 1019 1016 LHC boson 10 3 Weak fermion mH2 ~ All of known physics 10-18 ~ MPl2 mH2 ~ Solar System Gravity ~ - MPl2 Large virtual effects cancel order by order in perturbation theory Supersymmetry With or Without Prejudice? • The Minimal Supersymmetric Standard Model has ~120 parameters • Studies/Searches incorporate simplified versions – Theoretical assumptions @ GUT scale – Assume specific SUSY breaking scenarios (mSUGRA, GMSB, AMSB) – Small number of well-studied benchmark points • Studies incorporate various data sets • Does this adequately describe the true breadth of the MSSM and all its possible signatures? • The LHC is turning on, era of speculation will end, and we need to be ready for all possible signals Most Analyses Assume CMSSM Framework • CMSSM: m0, m1/2, A0, tanβ, sign μ • Χ2 fit to some global data set Prediction for Lightest Higgs Mass Fit to EW precision, B-physics observables, & WMAP Ellis etal arXiv:0706.0652 Spectrum for Best Fit CMSSM/NUHM Point NUHM includes two more parameters: MA, μ Buchmuller etal arXiv:0808.4128 Gluinos at the Tevatron Alwall, Le, Lisanti, Wacker arXiv:0803.0019 • Tevatron gluino/squark analyses performed solely for mSUGRA – constant ratio mgluino : mBino ≃ 6 : 1 Gluino-Bino mass ratio determines kinematics More Comprehensive MSSM Analysis Berger, Gainer, JLH, Rizzo, arXiv:0812.0980 • Study Most general CP-conserving MSSM – Minimal Flavor Violation – Lightest neutralino is the LSP – First 2 sfermion generations are degenerate w/ negligible Yukawas – No GUT, high-scale, or SUSY-breaking assumptions • ⇒ pMSSM: 19 real, weak-scale parameters scalars: mQ1, mQ3, mu1, md1, mu3, md3, mL1, mL3, me1, me3 gauginos: M1, M2, M3 tri-linear couplings: Ab, At, Aτ Higgs/Higgsino: μ, MA, tanβ Perform 2 Random Scans Linear Priors 107 points – emphasize Log Priors 2x106 points – emphasize 100 GeV msfermions 1 TeV 50 GeV |M1, M2, | 1 TeV 100 GeV M3 1 TeV ~0.5 MZ MA 1 TeV 1 tan 50 |At,b,| 1 TeV 100 GeV msfermions 3 TeV moderate masses lower masses and extend to higher masses 10 GeV |M1, M2, | 3 TeV 100 GeV M3 3 TeV ~0.5 MZ MA 3 TeV 1 tan 60 10 GeV ≤|A t,b,| 3 TeV Absolute values account for possible phases only Arg (Mi ) and Arg (Af ) are physical 2 . Stops/sbottoms • Check meson mixing Set of Experimental Constraints • Theoretical spectrum Requirements (no tachyons, etc) • Precision measurements: – Δ, (Z→ invisible) – Δ(g-2) ??? (30.2 8.8) x 10-10 (0809.4062) (29.5 7.9) x 10-10 (0809.3085) → (-10 to 40) x 10-10 to be conservative.. • Flavor Physics – b →s , B →τν, Bs →μμ – Meson-Antimeson Mixing : Constrains 1st/3rd sfermion mass ratios to be < 5 in MFV context Set of Experimental Constraints Cont. • Dark Matter – Direct Searches: CDMS, XENON10, DAMA, CRESST I – Relic density: h2 < 0.1210 → 5yr WMAP data • Collider Searches: complicated with many caveats! – LEPII: Neutral & Charged Higgs searches Sparticle production Stable charged particles – Tevatron: Squark & gluino searches Trilepton search Stable charged particles BSM Higgs searches Slepton & Chargino Searches at LEPII Sleptons Charginos Tevatron Squark & Gluino Search 2,3,4 Jets + Missing Energy (D0) Multiple analyses keyed to look for: Squarks-> jet +MET Gluinos -> 2 j + MET Feldman-Cousins 95% CL Signal limit: 8.34 events For each model in our scan we run SuSpect -> SUSY-Hit -> PROSPINO -> PYTHIA -> D0-tuned PGS4 fast simulation and compare to the data Tevatron: D0 Stable Particle (= Chargino) Search sleptons winos higgsinos Interpolation: M > 206 |U1w|2 + 171 |U1h|2 GeV •This is an incredibly powerful constraint on our model set! •No applicable bounds on charged sleptons..the cross sections are too small. Survival Statistics • Flat Priors: – 107 models scanned – 68.5K (0.68%) survive • Log Priors: – 2 x106 models scanned – 3.0k (0.15%) survive 9999039 slha-okay.txt 7729165 error-okay.txt 3270330 lsp-okay.txt 3261059 deltaRho-okay.txt 2168599 gMinus2-okay.txt 617413 b2sGamma-okay.txt 594803 Bs2MuMu-okay.txt 592195 vacuum-okay.txt 582787 Bu2TauNu-okay.txt 471786 LEP-sparticle-okay.txt 471455 invisibleWidth-okay.txt 468539 susyhitProb-okay.txt 418503 stableParticle-okay.txt 418503 chargedHiggs-okay.txt 132877 directDetection-okay.txt 83662 neutralHiggs-okay.txt 73868 omega-okay.txt 73575 Bs2MuMu-2-okay.txt 72168 stableChargino-2-okay.txt 71976 triLepton-okay.txt 69518 jetMissing-okay.txt 68494 final-okay.txt ATLAS CMS SU1 SU2 SU3 SU4 SU8 LM1 LM2 LM3 LM4 LM5 LM6 LM7 LM8 LM9 LM10 HM2 HM3 HM4 OK killed by LEP killed by h2 killed by b→s killed by g-2 killed by Higgs killed by g-2 killed by b→s killed by h2 killed by h2 OK killed by LEP killed by h2 killed by LEP OK killed by h2 killed by h2 killed by h2 Fate of Benchmark Points! Most well-studied models do not survive confrontation with the latest data. For many models this is not the unique source of failure Similarly for the SPS Points SPS1a killed by b →s SPS1a’ OK SPS1b killed by b →s SPS2 killed by h2 (GUT) / OK(low) SPS3 killed by h2 (low) / OK(GUT) SPS4 killed by g-2 SPS5 killed by h2 SPS6 OK SPS9 killed by Tevatron stable chargino Predictions for Observables (Flat Priors) b → sγ g-2 Exp’t SM Bs →μμ BSM = 3.5 x 10-9 Relic Density Predictions for Lightest Higgs Mass Flat Priors Log Priors Predictions for Heavy & Charged Higgs Flat Priors tan β Distribution of Squark Masses Flat Priors Stops Sbottoms Distribution of Gaugino Masses Flat Priors Gluino Charginos Neutralinos Composition of the LSP Flat Priors Log Priors Character of the NLSP: it can be anything! Flat Priors Log Priors NLSP-LSP Mass Splitting Flat Priors NLSP-LSP Mass Splitting: Details ~ Χ 20 ~ Χ 1+ ~ eR ~ u L Naturalness Criterion Barbieri, Giudice Kasahara, Freese, Gondolo Flat Priors Less Log Priors More Fine tuned Δ Δ Flat Priors Log Priors We have many more classifications! Flat Priors: 1109 Classes Log Priors: 267 Classes The LHC is Turning On!!!!!!!! What can BSM theorists do until the data starts pouring in? • More & more New Models: New models are most useful if they contain new signatures Biggest worry is whether triggers cover all NP possibilities • Fully compute the signatures of current NP models • Fully implement NP models into Monte Carlos Let the fun begin! Discoveries at the LHC will find the vintage nature has bottled. Back-up ILC Search Region: Sleptons and EW Gauginos Flat Priors: MSUSY ≤ 1 TeV Log Priors: MSUSY ≤ 3 TeV x-axis legend ILC Search Region: Squarks and Gluinos Flat Priors: MSUSY ≤ 1 TeV Log Priors: MSUSY ≤ 3 TeV Black Hole Production @ LHC: Dimopoulos, Landsberg Giddings, Thomas Black Holes produced when s > M* Classical Approximation: E/2 b [space curvature << E] b < Rs(E) BH forms E/2 Geometric Considerations: Naïve = Rs2(E), details show this holds up to a factor of a few Production rate is enormous! Determination of Number of Large Extra Dimensions 1 per sec at LHC! JLH, Lillie, Rizzo hep-ph/0503178 Black-Max: a New BH Generator Dai, Starkman, Stojkevic, Issever, Rizvi, Tseng, arXiv:0711.3012 • Simulates more realistic models – Greybody factors – BH rotation – BH recoil due to Hawking radiation – Brane tension – Split fermions • Dramatic effects on kinematic properties • Interfaces w/ Herwig & Pythia Energy Distbt’n of emitted particles No new effects Split Fermions Brane tension Rotating Distribution for Selectron/Sneutrino Masses Flat Priors Log Priors Distribution of Stau Masses Flat Priors Log Priors Dark Matter Direct Detection Cross Sections Flat Priors Log Priors Spin Dependent Spin Spin Independent Independent Distinguishing Dark Matter Models Barger etal Flat Priors Little Higgs Gauge Production WZ WH WZ 2j + 3l + Azuelos etal, hep-ph/0402037 Birkedal, Matchev, Perelstein, hep-ph/0412278 Density of Stopped Gluinos in ATLAS Arvanitaki, etal hep-ph/0506242 See also ATLAS study, Kraan etal hep-ph/0511014