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Extra Dimensions with Many Inverse Femptobarns at the Tevatron

Extra Dimensions with Many Inverse Femptobarns at the Tevatron. Universal Extra Dimensions Warped Extra Dimensions – Beyond RS1 - SM in the bulk Brane Kinetic Terms Extended Manifolds Higgsless Models of EWSB Truly Exotic Branon Production. Mini-BSM Workshop. J. Hewett.

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Extra Dimensions with Many Inverse Femptobarns at the Tevatron

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  1. Extra Dimensions with Many Inverse Femptobarns at the Tevatron • Universal Extra Dimensions • Warped Extra Dimensions – Beyond RS1 - SM in the bulk • Brane Kinetic Terms • Extended Manifolds • Higgsless Models of EWSB • Truly Exotic • Branon Production Mini-BSM Workshop J. Hewett

  2. Universal Extra Dimensions

  3. Universal Extra Dimensions Appelquist, Cheng, Dobrescu • All SM fields in TeV-1, 5d, S1/Z2 bulk • No branes!  translational invariance is preserved  tree-level conservation of p5 • KK number conserved at tree-level • broken at higher order by boundary terms • KK parity conserved to all orders, (-1)n Consequences: • KK excitations only produced in pairs Relaxation of collider & precision EW constraints Rc-1≥ 300 GeV • Lightest KK particle is stable (LKP) and is Dark Matter candidate • Boundary terms separate masses and give SUSY-like spectrum

  4. Phenomenology looks like Supersymmetry: Heavier particles cascade down to LKP LKP: Photon KK state appears as missing ET SUSY-like Spectroscopy Confusion with SUSY if discovered @ LHC ! Universal Extra Dimensions: Bosonic SUSY Spectrum looks like SUSY ! No Tevatron exp’t limits to date! Chang, Matchev,Schmaltz

  5. 1st Excitation Quark Production @ Tevatron Production Processes ii, v, iii i, iv Rizzo, hep-ph/0106336

  6. How to distinguish SUSY from UED I: • Observe KK states in e+e- annihilation • Measure their spin via: • Threshold production, s-wave • vs p-wave • Distribution of decay products • However, could require CLIC • energies... JLH, Rizzo, Tait Datta, Kong, Matchev

  7. How to distinguish SUSY from UED II: Datta, Kong, Matchev Observe higher level (n = 2) KK states: • Pair production of q2q2, q2g2, V2 V2 • Single production of V2 via (1) small KK number breaking couplings and (2) from cascade decays of q2 Discovery reach @ Tevatron/LHC

  8. How to distinguish SUSY from UED III: Measure the spins of the KK states – Difficult! Decay chains in SUSY and UED: Form charge asymmetry: Smillie, Webber Works for some, but not all, regions of parameter space

  9. Warped Extra Dimensions

  10. Localized Gravity: Warped Extra Dimensions Randall, Sundrum Bulk = Slice of AdS5 5 = -24M53k2 k = curvature scale Naturally stablized via Goldberger-Wise Hierarchy is generated by exponential!

  11. 4-d Effective Theory Davoudiasl, JLH, Rizzo hep-ph/9909255 KK Graviton Wavefunction & Interactions: Phenomenology governed by two parameters:  or m1 ~ TeV k/MPl≲ 0.1 5-d curvature: |R5| = 20k2 < M52

  12. Drell-Yan Production: Randall-Sundrum Graviton Resonances - Tevatron: pp  G(1)  ℓ+ℓ- 1st & 2nd KK cross sections Different curves for k/MPl = 0.1 – 1.0 Davoudiasl, JLH, Rizzo

  13. Tevatron limits on RS Gravitons CDF Drell-Yan spectrum

  14. Peeling the Standard Model off the Brane • Model building scenarios require SM bulk fields • Gauge coupling unification • Supersymmetry breaking •  mass generation • Fermion mass hierarchy • …. SM gauge fields alone in the bulk violate custodial symmetry! Gauge boson KK towers have coupling gKK = 8.4gSM !! Precision EW Data Constrains: m1A > 25 TeV   > 100 TeV! Davoudiasl, JLH, Rizzo Pomarol Fix 1: Enlarge EW gauge group to SU(2)L x SU(2)R , preserves custodial symmetry Agashe, Sundrum

  15. Fix 2: Add Fermions in the Bulk Ghergetta, Pomarol Davoudiasl, JLH, Rizzo • Introduces new parameter, related to fermion Yukawa • mfbulk = k, with  ~ O(1) and determines location in bulk • Zero-mode fermions couple weaker to gauge KK states than brane fermions Precision EW & collider constraints on mass of 1st gauge KK state LHC Tevatron k/MPl = 1, 0.1, 0.01 towards Planck brane towards TeV brane

  16. Graviton Branching Fractions Fermions on TeV brane Fermions in bulk dijets tops leptons Higgs gluons WW ZZ/ B = 2Bℓℓ m1 = 1 TeV Davoudiasl, JLH, Rizzo, hep-ph/0006041

  17. Phenomenology Summary for Bulk Fermions Precision EW Davoudiasl, JLH, Rizzo, hep-ph/0006041

  18. Fix 3: Brane Kinetic Terms Dvali etal • Originally introduced to allow infinite 5th dimension recover 4-d behavior at short distances • Generated at loop-order from brane quantum effects of orbifold and/or matter fields on brane • Required as brane counter terms for bulk quantum effects Georgi etal • Brane kinetic terms are naturally present!! Their size is determined by the full UV theory Appears in the action for bulk fields: SGravity = M53/4  d4x rcd (-G) {R(5) + (2/krc)[0() + (-)]R(4)} SGauge = ∫ d5x [-FMNFMN/(4g52) - (x5) FF/(4ga2)] 0, are free parameters

  19. BKT’s modify KK spectra – masses & couplings Randall-Sundrum model: graviton fields in the bulk KK coupling strength e+e- +- 0 = 0 n=1 2 3 …  = 1, -1, -2, -10 Davoudiasl, JLH, Rizzo, hep-ph/0305086

  20. Tevatron Search Reach: RS Gravitons with BKTs 1st Excitation search reach Run I Run II, 5 fb-1 0 = 0 Curvature parameter is varied Allows for very light Gravitons! Davoudiasl, JLH, Rizzo, hep-ph/0305086

  21. BKT’s modify KK spectra – masses & couplings Randall-Sundrum model: gauge fields in the bulk Precision EW bound on 1st KK state KK coupling strength Davoudiasl, JLH, Rizzo, hep-ph/0212279 See also Carena etal, hep-ph/0212307

  22. Extend Manifold: AdS5 x S Drastically modifies Graviton KK spectrum! Drell-Yan (LHC) e+e-+- ( = 1) Gives a forest of KK graviton resonances! Davoudiasl, JLH, Rizzo hep-ph/0211377

  23. Higgsless EWSB

  24. What good is a Higgs anyway?? • Generates W,Z Masses • Generates fermion Masses • Unitarizes scattering amplitudes (WLWL WLW L ) Do we really need a Higgs? And get everything we know right…. Our laboratory: Standard Model in 1 extra warped dimension  Minimal Particle Content!

  25. Generating Masses Consider a massless 5-d field ∂2 = (∂∂ - ∂52 )  = 0 looks like (∂∂ - m2 )  = 0 (KK tower) The curvature of the 5-d wavefunction  is related to its mass

  26. Toy Example:Flat space with U(1) gauge field in bulk with S1/Z2 Orbifold A(y) ~ cos (ny/R) A5(y) ~ sin (ny/R) Orbifold Boundary Conditions: ∂5A = 0 A5 = 0 1st KK 0-mode 0-mode is flat & y independent  m0 = 0 R 0 If The Same boundary conditions are applied at both boundaries, 0-mode is massless and U(1) remains unbroken

  27. 1st KK Orbifold Boundary Conditions: ∂5A = 0 A5 = 0 0-mode A(y) ~ nan cos(mny) + bn sin(mny) ∂5A(y) ~ mnn(-an sin(mny) + bn cos(mny) BC’s: A(y=0) = 0  an = 0 ∂5A(y=R) = 0  cos(mnR) = 0 A cannot be flat with these boundary conditions! ∂5A=0 A=0 The zero mode is massive! A5 acts as a Goldstone U(1) is broken mn = (n + ½)/R

  28. Unitarity in Gauge Boson Scattering • SM without Higgs violates perturbative unitarity in • WLWL WLWL at s ~ 1.7 TeV • Higgs restores unitarity if mH < TeV • What do we do without a Higgs?? Exchange gauge KK towers: Conditions on KK masses & couplings: (g1111)2 = k (g11k)2 4(g1111)2 M12 = k (g11k)2 Mk2 Csaki etal, hep-ph/0305237 Necessary, but not sufficient, to guarantee perturbative unitarity!

  29. Realistic Framework: Agashe etal hep-ph/0308036 Csaki etal hep-ph/0308038 SU(2)L x SU(2)R x U(1)B-L in 5-d Warped bulk Planck brane BC’s restricted by variation of the action at boundary TeV-brane SU(2)L x SU(2)R SU(2) Custodial Symmetry is preserved! SU(2)D SU(2)R x U(1)B-L W, Z get TeV scale masses  left massless! U(1)Y WR, ZR get Planck scale masses Parameters:  = g5R/g5L (restricted range) L,Y,B,D brane kinetic terms g5L fixed by GF ,  = g5B/g5L fixed by MZ

  30. Gauge KK Spectrum Effects of Brane terms n~ z[an J1(mnz) + bn Y1(mnz)], z=eky/k  = 1 Masses are fixed by model parameters Schematic KK Spectra Every other neutral gauge KK level is degenerate! Brane terms split this degeneracy And give lighter KK states Davoudiasl, JLH, Lillie, Rizzo hep-ph/0312193,0403300

  31. What are the preferred gauge KK masses? Tension Headache: PUV in WW scattering needs light KK’s Colliders Important direct constraints Precision EW needs heavier KK’s Is there a consistent region of parameter space?

  32. Scale of unitarity violation in WL scattering Precision EW pseudo-oblique parameters Davoudiasl, JLH, Lillie, Rizzo hep-ph/0312193,0403300

  33. Collider Constraints with Run I data

  34. Monte Carlo Exploration of Parameter space Points which pass all constraints except PUV: (none pass PUV!) Over 3M points scanned Prefers light Z’ with small couplings Perfect for the Tevatron Run II !! Realistic models put fermions in the bulk JLH, Lillie, Rizzo hep-ph/0407059

  35. Truly Exotic

  36. Branon Production Cembranos, Dobado, Moroto hep-ph/0405286 Creminelli, Strumia, hep-ph/0007267 Branon - fields associated with brane fluctuations along extra dimensions. Pseudo-goldstone bosons from spontaneous breaking of translational invariance.  Are expected to be light. Interact with SM fields via T Parameters: N = # of Branons f = Brane tension scale M = Branon mass • Parity requires branons to be produced in pairs • Branons couple ~ f-1  are weakly interacting, Dark • Matter candidates • Appear as missing ET in detector

  37. - Production processes: • gg  g, qq  g, , qg  q • Monojet/photon + missing ET Run II `Projections” Run I N=1 200 pb-1 D0 Monojet data CDF single photon data

  38. There are numerous discovery opportunities for the Tevatron for the remainder of Run II !

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