Extra Dimensions: From Colliders to Cosmology

1. Extra Dimensions: From Colliders to Cosmology • Large Extra Dimensions (Primordial Black Holes) • Universal Extra Dimensions (KK Bino) • Warped Extra Dimensions (KK R) Collider signals & DM properties* * Thanks to T. Tait! J. Hewett Michell Symposium 2007

2. Kaluza-Klein tower of particles E2 = (pxc)2 + (pyc)2 + (pzc)2 + (pextrac)2 + (mc2)2 In 4 dimensions, looks like a mass! pextra is quantized = n/R Tower of massive particles Large radius gives finely separated Kaluza-Klein particles Small radius gives well separated Kaluza-Klein particles Small radius Large radius

3. Large Extra Dimensions Arkani-Hamed, Dimopoulos, Dvali, SLAC-PUB-7801 Motivation: solve the hierarchy problem by removing it! SM fields confined to 3-brane Gravity becomes strong in the bulk Gauss’ Law: MPl2 = V MD2+ , V = Rc  MD = Fundamental scale in the bulk ~ TeV

4. Kaluza-Klein Modes in a Detector Indirect Signature Missing Energy Signature pp  g + Gn Vacavant, Hinchliffe JLH

5. Graviton Exchange Modified with Running Gravitational Coupling Insert Form Factor in coupling to parameterize running M*D-2 [1+q2/t2M*2 ]-1 Could reduce signal! t= 1 SM 0.5 D=3+4 M* = 4 TeV JLH, Rizzo, to appear

6. Constraints from Astrophysics/Cosmology Cullen, Perelstein Barger etal, Savage etal • Supernova Cooling NN  NN + Gn can cool supernova too rapidly • Cosmic Diffuse  Rays NN  NN + Gn    Gn   • Matter Dominated Universe too many KK states • Neutron Star Heat Excess NN  NN + Gn becomes trapped in neutron star halo and heats it Hannestad, Raffelt Hall, Smith - Fairbairn Hannestad, Raffelt

7. Astrophysical Constaints*: MD in TeV Hannestad, Raffelt  = 2 3 4 5 Supernova Cooling 9 0.66 0.01 Cosmic Diffuse -rays Sne 28 1.65 0.02 Sne Cas A 14 1.2 0.02 Neutron Star 39 2.6 0.4 Matter Dominated Universe 85 7 1.5 Neutron Star Heat Excess 700 25 2.8 0.57 Low MD disfavored for  ≤ 3 * Can be evaded with hyperbolic manifolds - Starkman, Stojkovic, Trodden

8. Black Hole Production @ LHC: Dimopoulos, Landsberg Giddings, Thomas Black Holes produced when s > M* Classical Approximation: [space curvature << E] E/2 b < Rs(E)  BH forms b E/2 Geometric Considerations: Naïve = Rs2(E), details show this holds up to a factor of a few

9. Black Hole event simulation @ LHC

10. Decay Properties of Black Holes (after Balding): Decay proceeds by thermal emission of Hawking radiation n determined to n = 0.75 @ 68% CL for n=2-6 from TH and  This procedure doesn’t work for large n At fixed MBH, higher dimensional BH’s are hotter: N ~ 1/T  higher dimensional BH’s emit fewer quanta, with each quanta having higher energy Multiplicity for n = 2 to n = 6 Harris etal hep-ph/0411022

11. pT distributions of Black Hole decays Provide good discriminating power for value of n Generated using modified CHARYBDIS linked to PYTHIA with M* = 1 TeV

12. Production rate is enormous! Determination of Number of Large Extra Dimensions 1 per sec at LHC! JLH, Lillie, Rizzo

13. Primordial Microscopic Black Holes • Produced in high-energy collisions in early universe • Rapid growth by absorption of matter from surrounding plasma Empty Bulk Mass density determined by TI Excluded • Demand: • Black Holes not overclose the universe • Must not dominate energy density during BBN Thermalized Bulk Conley, Wizansky

14. 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

15. Phenomenology looks like Supersymmetry: Heavier KK 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 ! Chang, Matchev,Schmaltz

16. 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

17. 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 @ LHC

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

19. Identity of the LKP • Boundary terms (similar to SUSY soft-masses) • Induced @ loop-level (vanish @ cut-off) • Determine masses & couplings of entire KK tower • 1 ≪ 2 ≪ 3 • Smallest corrections to U(1) KK state • NLKP is eR(1) • M ~ 1/R > v • LKP is almost pure Bino KK B(1) Bino-Wino mass matrix, n=1

20. Thermal Production and Freeze Out • Assume LKP in thermal equilibrium in early universe • Falls out of equilibrium as universe expands • Below freeze-out, density of LKP WIMPS per co-moving volume is fixed For 1 TeV KK, Tf = 40 TeV

21. Co-annihilation • eR(1) may substantially affect relic density if it is close in mass to B(1) • eR(1) has same interaction efficiency • freeze-out temp is unaffected • eR(1) left after freeze-out • Eventually eR(1) e(0) + B(1) • Net relic density of B(1) is increased

22. Relic Density  = scaled mass splitting between eR(1) and B(1)  = 0.05 • = 0.01 h2 = 0.11  0.006 yields for R: … 1 flavor …5 flavors B(1) alone 5d range of 600-900 GeV 6d range of 425-625 GeV Tait, Servant

23. More Complete Calculations WMAP  = 0.01 solid 0.05 dashed Quasi-degenerate KK quarks and gluons Quasi-degenerate KK eL(1) Kong, Matchev Burnell, Kribs

24. Add Gravity in the Bulk mG1 > mB1 mG1 < mB1 KK graviton decays into B(1) (mWG = KK scale from relic density without graviton) Super-WIMPS! Feng, Rajaraman, Takayama Shah, Wagner

25. Direct Detection of LKP • LKP – nucleon scattering: Tait, Servant

26. 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!

27. Kaluza-Klein Modes in a Detector: SM on the brane Number of Events in Drell-Yan @ LHC For this same model embedded in a string theory: AdS5 x S Unequal spacing signals curved space Davoudiasl, JLH, Rizzo

28. 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 @ LHC gg  Gn  ZZ @ LHC Lillie, Randall, Wang Agashe, Davoudiasl, Perez, Soni

29. Issue: Top Collimation - gg  gn  tt g1 = 4 TeV g1 = 2 TeV Lillie, Randall, Wang

30. Warped Extra Dimension with SO(10) in the bulk • Splits families amongst 16 of SO(10) with different Z3 charges: Baryon symmetry in bulk • Lightest Z-odd particle, R’ KK state, is stable Bold-face particles have zero-modes Gives correct relic density for wide range of masses Agashe, Servant

32. Cosmic Ray Sensitivity to Black Hole Production No suppression Ringwald, Tu Anchordoqui etal

33. Summary of Exp’t Constraints on MD Anchordoqui, Feng Goldberg, Shapere