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LISHEP09 J Hewett, SLAC Anticipating New Physics at the LHC
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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!
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A Cellar of New Ideas ’67 The Standard Model ’77 Vin de Technicolor ’70’s Supersymmetry: MSSM ’90’s SUSY Beyond MSSM ’90’s CP Violating Higgs ’98 Extra Dimensions ’02 Little Higgs ’03 Fat Higgs ’03 Higgsless ’04 Split Supersymmetry ’05 Twin Higgs a classic! aged to perfection better drink now mature, balanced, well developed - the Wino’s choice complex structure sleeper of the vintage what a surprise! svinters blend all upfront, no finish lacks symmetry young, still tannic needs to develop bold, peppery, spicy uncertain terrior J. Hewett finely-tuned double the taste
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Last Minute Model Building Anything Goes! Non-Communtative Geometries Return of the 4 th Generation Hidden Valleys Quirks – Macroscopic Strings Lee-Wick Field Theories Unparticle Physics ….. (We stilll have a bit more time)
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The Hierarchy Problem Energy (GeV) 10 19 10 16 10 3 10 -18 Solar System Gravity Weak GUT Planck desert LHC All of known physics m H 2 ~~ M Pl 2 Quantum Corrections: Virtual Effects drag Weak Scale to M Pl
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The Hierarchy Problem: Little Higgs Energy (GeV) 10 19 10 16 10 3 10 -18 Solar System Gravity Weak GUT Planck LHC All of known physics Stacks of Little Hierarchies 10 4 New Physics! Simplest Model: The Littlest Higgs with 1 ~ 10 TeV 2 ~ 100 TeV 3 ~ 1000 TeV ….. 10 5 10 6...... New Physics!
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3-Scale Model ~ 10 TeV: New Strong Dynamics Global Symmetry f ~ /4 ~ TeV: Symmetires Broken Pseudo-Goldstone Scalars New Gauge Fields New Fermions v ~ f/4 ~ 100 GeV: Light Higgs SM vector bosons & fermions Sample Spectrum Signal @ LHC
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The Hierarchy Problem: Extra Dimensions Energy (GeV) 10 19 10 16 10 3 10 -18 Solar System Gravity Weak – Quantum Gravity GUT Planck desert LHC All of known physics Simplest Model: Large Extra Dimensions = Fundamental scale in 4 + dimensions M Pl 2 = (Volume) M D 2+ Gravity propagates in D = 3+1 + dimensions Arkani-Hamed, Dimopoulis, Dvali
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Kaluza-Klein Gravitons in a Detector M ee [GeV] Events / 50 GeV / 100 fb -1 10 2 10 1 10 -1 10 -2 LHC Indirect SignatureMissing Energy Signature pp g + G n JLHVacavant, Hinchliffe
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Signals for Gravitational Fixed Points Fixed point renders GR non-perturbatively renormalizable and asymptotically safe Gravity runs such that it becomes weaker at higher energies Collider signals if √s ~ M Pl Graviton Exchange Modified Graviton Emission generally unaffected Parameterize by form factor in coupling Could reduce signal! D=3+4 M * = 4 TeV SM t= 1 0.5 JLH, Rizzo, arXiv:0707.3182 Litim, Pheln, arXiv:0707.3983 Drell-Yan
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The Hierarchy Problem: Extra Dimensions Energy (GeV) 10 19 10 16 10 3 10 -18 Solar System Gravity Weak GUT Planck desert LHC All of known physics Model II: Warped Extra Dimensions wk = M Pl e -kr strong curvature Randall, Sundrum
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Number of Events in Drell-Yan For this same model embedded in a string theory: AdS 5 x S Kaluza-Klein Gravitons in a Detector: SM on the brane Davoudiasl, JLH, Rizzo Spin-2 resonances in Drell-Yan
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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 G n ZZ gg g n tt Agashe, Davoudiasl, Perez, Soni hep-ph/0701186 - Lillie, Randall, Wang, hep-ph/0701164
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Issue: Top Collimation Lillie, Randall, Wang, hep-ph/0701164 gg g n tt - g 1 = 2 TeV g 1 = 4 TeV
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The Hierarchy Problem: Higgsless Energy (GeV) 10 19 10 16 10 3 10 -18 Solar System Gravity Weak GUT Planck desert LHC All of known physics Warped Extra Dimensions wk = M Pl e -kr With NO Higgs boson! strong curvature Csaki, Grojean,Murayama, Pilo, Terning
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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) R x U(1) B-L U(1) Y SU(2) L x SU(2) R SU(2) D SU(2) Custodial Symmetry is preserved! W R , Z R get Planck scale masses W , Z get TeV scale masses left massless! BC’s restricted by variation of the action at boundary
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Exchange gauge KK towers: Conditions on KK masses & couplings: (g 1111 ) 2 = k (g 11k ) 2 4(g 1111 ) 2 M 1 2 = k (g 11k ) 2 M k 2 Necessary, but not sufficient, to guarantee perturbative unitarity! Some tension with precision EW Csaki etal, hep-ph/0305237 Unitarity in Gauge Boson Scattering: What do we do without a Higgs?
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Production of Gauge KK States @ LHC gg, qq g 1 dijets - Davoudiasl, JLH, Lilllie, RizzoBalyaev, Christensen
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Gauge Hierarchy Problem Cosmological Constant Problem Planck Scale Weak Scale Cosmological Scale The Hierarchy Problem: Who Cares!! We have much bigger Problems!
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Split Supersymmetry : Energy (GeV) M GUT ~ 10 16 GeV M S : SUSY broken at high scale ~ 10 9-13 GeV M weak 1 light Higgs + Fermions protected by chiral symmetry Scalars receive mass @ high scale Arkani-Hamed, Dimopoulis hep-ph/0405159 Giudice, Romanino hep-ph/0406088
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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 g ~ q ~ q q 1010 Rate ~ 0, due to heavy squark masses! Gluino pair + jet cross section JLH, Lillie, Masip, Rizzo hep-ph/0408248 100 fb -1
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The Hierarchy Problem: Supersymmetry Energy (GeV) 10 19 10 16 10 3 10 -18 Solar System Gravity Weak GUT Planck desert LHC All of known physics m H 2 ~~ M Pl 2 Quantum Corrections: Virtual Effects drag Weak Scale to M Pl m H 2 ~ ~ - M Pl 2 boson fermion Large virtual effects cancel order by order in perturbation theory
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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
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Most Analyses Assume CMSSM Framework CMSSM: m 0, m 1/2, A 0, tanβ, sign μ Χ 2 fit to some global data set Prediction for Lightest Higgs Mass Fit to EW precision, B-physics observables, & WMAP Ellis etal arXiv:0706.0652
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Spectrum for Best Fit CMSSM/NUHM Point Buchmuller etal arXiv:0808.4128 NUHM includes two more parameters: M A, μ
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Gluinos at the Tevatron Tevatron gluino/squark analyses performed solely for mSUGRA – constant ratio m gluino : m Bino ≃ 6 : 1 Alwall, Le, Lisanti, Wacker arXiv:0803.0019 Gluino-Bino mass ratio determines kinematics
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More Comprehensive MSSM Analysis 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: m Q 1, m Q 3, m u 1, m d 1, m u 3, m d 3, m L 1, m L 3, m e 1, m e 3 gauginos: M 1, M 2, M 3 tri-linear couplings: A b, A t, A τ Higgs/Higgsino: μ, M A, tanβ Berger, Gainer, JLH, Rizzo, arXiv:0812.0980
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Perform 2 Random Scans Linear Priors 10 7 points – emphasize moderate masses 100 GeV m sfermions 1 TeV 50 GeV |M 1, M 2, | 1 TeV 100 GeV M 3 1 TeV ~0.5 M Z M A 1 TeV 1 tan 50 |A t,b, | 1 TeV Log Priors 2x10 6 points – emphasize lower masses and extend to higher masses 100 GeV m sfermions 3 TeV 10 GeV |M 1, M 2, | 3 TeV 100 GeV M 3 3 TeV ~0.5 M Z M A 3 TeV 1 tan 60 10 GeV ≤|A t,b, | 3 TeV Absolute values account for possible phases only Arg (M i ) and Arg (A f ) are physical
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Check meson mixing. Stops/sbottoms 2
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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, B s →μμ –Meson-Antimeson Mixing : Constrains 1st/3rd sfermion mass ratios to be < 5 in MFV context
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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
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Slepton & Chargino Searches at LEPII Sleptons Charginos
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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
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Tevatron: D0 Stable Particle (= Chargino) Search This is an incredibly powerful constraint on our model set! No applicable bounds on charged sleptons..the cross sections are too small. Interpolation: M > 206 |U 1w | 2 + 171 |U 1h | 2 GeV sleptons winos higgsinos
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Survival Statistics Flat Priors: –10 7 models scanned –68.5K (0.68%) survive Log Priors: –2 x10 6 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
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SU1 OK SU2 killed by LEP SU3 killed by h 2 SU4 killed by b →s SU8 killed by g-2 LM1 killed by Higgs LM2 killed by g-2 LM3 killed by b →s LM4 killed by h 2 LM5 killed by h 2 LM6 OK LM7 killed by LEP LM8 killed by h 2 LM9 killed by LEP LM10 OK HM2 killed by h 2 HM3 killed by h 2 HM4 killed by h 2 ATLAS CMS Most well-studied models do not survive confrontation with the latest data. For many models this is not the unique source of failure Fate of Benchmark Points!
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SPS1a killed by b →s SPS1a’ OK SPS1b killed by b →s SPS2 killed by h 2 (GUT) / OK(low) SPS3 killed by h 2 (low) / OK(GUT) SPS4 killed by g-2 SPS5 killed by h 2 SPS6 OK SPS9 killed by Tevatron stable chargino Similarly for the SPS Points
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Predictions for Observables (Flat Priors) Exp’t SM B s →μμ B SM = 3.5 x 10 -9 b → sγ g-2 Relic Density
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Predictions for Lightest Higgs Mass Flat PriorsLog Priors
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Predictions for Heavy & Charged Higgs Flat Priors tan β
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Distribution of Squark Masses Flat Priors Stops Sbottoms
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Distribution of Gaugino Masses Flat Priors Gluino Charginos Neutralinos
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Composition of the LSP Flat Priors Log Priors
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Character of the NLSP: it can be anything! Flat PriorsLog Priors
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NLSP-LSP Mass Splitting Flat Priors
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NLSP-LSP Mass Splitting: Details Χ1+Χ1+ Χ20Χ20 eReR uLuL ~ ~ ~ ~
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Naturalness Criterion Flat Priors Log Priors Barbieri, Giudice Kasahara, Freese, Gondolo ΔΔ LessMore Fine tuned
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Flat PriorsLog Priors We have many more classifications! Flat Priors: 1109 Classes Log Priors: 267 Classes
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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!
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Discoveries at the LHC will find the vintage nature has bottled.
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Back-up
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ILC Search Region: Sleptons and EW Gauginos Flat Priors: M SUSY ≤ 1 TeV Log Priors: M SUSY ≤ 3 TeV x-axis legend
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ILC Search Region: Squarks and Gluinos Flat Priors: M SUSY ≤ 1 TeVLog Priors: M SUSY ≤ 3 TeV
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Black Hole Production @ LHC: Black Holes produced when s > M * Classical Approximation: [space curvature << E] E/2 b b < R s (E) BH forms Geometric Considerations: Naïve = R s 2 (E), details show this holds up to a factor of a few Dimopoulos, Landsberg Giddings, Thomas
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Production rate is enormous! 1 per sec at LHC! JLH, Lillie, Rizzo hep-ph/0503178 Determination of Number of Large Extra Dimensions
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Black-Max: a New BH Generator 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 Rotating Brane tension Split Fermions No new effects Dai, Starkman, Stojkevic, Issever, Rizvi, Tseng, arXiv:0711.3012
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Distribution for Selectron/Sneutrino Masses Flat PriorsLog Priors
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Distribution of Stau Masses Flat PriorsLog Priors
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Dark Matter Direct Detection Cross Sections Flat PriorsLog Priors Spin Dependent Spin Independent
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Distinguishing Dark Matter Models Flat Priors Barger etal
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Little Higgs Gauge Production Azuelos etal, hep-ph/0402037 Birkedal, Matchev, Perelstein, hep-ph/0412278 WZ W H WZ 2j + 3l +
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Density of Stopped Gluinos in ATLAS See also ATLAS study, Kraan etal hep-ph/0511014 Arvanitaki, etal hep-ph/0506242
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