Download presentation

Presentation is loading. Please wait.

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

2
Kaluza-Klein tower of particles E 2 = (p x c) 2 + (p y c) 2 + (p z c) 2 + (p extra c) 2 + (mc 2 ) 2 In 4 dimensions, looks like a mass! p extra is quantized = n/R Small radiusLarge radius Small radius gives well separated Kaluza-Klein particles Large radius gives finely separated Kaluza- Klein particles Tower of massive particles

3
Large Extra Dimensions Motivation: solve the hierarchy problem by removing it! SM fields confined to 3-brane Gravity becomes strong in the bulk Arkani-Hamed, Dimopoulos, Dvali, SLAC-PUB-7801 Gauss’ Law: M Pl 2 = V M D 2+ , V = R c M D = Fundamental scale in the bulk ~ TeV

4
Kaluza-Klein Modes in a Detector Indirect SignatureMissing Energy Signature pp g + G n JLH Vacavant, Hinchliffe

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

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

7
Astrophysical Constaints * : M D in TeV = 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 M D disfavored for ≤ 3 * Can be evaded with hyperbolic manifolds - Starkman, Stojkovic, Trodden Hannestad, Raffelt

8
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

9
Black Hole event simulation @ LHC

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

11
p T 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! 1 per sec at LHC! JLH, Lillie, Rizzo Determination of Number of Large Extra Dimensions

13
Primordial Microscopic Black Holes Produced in high-energy collisions in early universe Rapid growth by absorption of matter from surrounding plasma Demand: 1.Black Holes not overclose the universe 2.Must not dominate energy density during BBN Mass density determined by T I Conley, Wizansky Excluded Empty Bulk Thermalized Bulk

14
Universal Extra Dimensions All SM fields in TeV -1, 5d, S 1 /Z 2 bulk No branes! translational invariance is preserved tree-level conservation of p 5 KK number conserved at tree-level broken at higher order by boundary terms KK parity conserved to all orders, (-1) n Consequences: 1.KK excitations only produced in pairs Relaxation of collider & precision EW constraints R c -1 ≥ 300 GeV! 2.Lightest KK particle is stable (LKP) and is Dark Matter candidate 3.Boundary terms separate masses and give SUSY-like spectrum Appelquist, Cheng, Dobrescu

15
Universal Extra Dimensions: Bosonic SUSY Phenomenology looks like Supersymmetry: Heavier KK particles cascade down to LKP LKP: Photon KK state appears as missing E T SUSY-like Spectroscopy Confusion with SUSY if discovered @ LHC ! Chang, Matchev,Schmaltz Spectrum looks like SUSY !

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: Observe higher level (n = 2) KK states: –Pair production of q 2 q 2, q 2 g 2, V 2 V 2 –Single production of V 2 via (1) small KK number breaking couplings and (2) from cascade decays of q 2 Discovery reach @ LHC Datta, Kong, Matchev

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 e R (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, T f = 40 TeV

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

22
Relic Density = scaled mass splitting between e R (1) and B (1) = 0.05 = 0.01 h 2 = 0.11 0.006 yields for R: Tait, Servant … 1 flavor … 5 flavors 5d range of 600-900 GeV 6d range of 425-625 GeV B (1) alone

23
More Complete Calculations WMAP Kong, MatchevBurnell, Kribs Quasi-degenerate KK e L (1) Quasi-degenerate KK quarks and gluons = 0.01 solid 0.05 dashed

24
Add Gravity in the Bulk m G1 > m B1 m G1 < m B1 KK graviton decays into B (1) (m WG = KK scale from relic density without graviton) Shah, Wagner Super-WIMPS! Feng, Rajaraman, Takayama

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

26
Localized Gravity: Warped Extra Dimensions Randall, Sundrum Bulk = Slice of AdS 5 5 = -24M 5 3 k 2 k = curvature scale Naturally stablized via Goldberger-Wise Hierarchy is generated by exponential!

27
Number of Events in Drell-Yan @ LHC For this same model embedded in a string theory: AdS 5 x S Kaluza-Klein Modes in a Detector: SM on the brane Davoudiasl, JLH, Rizzo Unequal spacing signals curved space

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 G n ZZ @ LHC gg g n tt @ LHC Agashe, Davoudiasl, Perez, Soni - Lillie, Randall, Wang

29
Issue: Top Collimation Lillie, Randall, Wang gg g n tt - g 1 = 2 TeV g 1 = 4 TeV

30
Warped Extra Dimension with SO(10) in the bulk Splits families amongst 16 of SO(10) with different Z 3 charges: Baryon symmetry in bulk Lightest Z-odd particle, R ’ KK state, is stable Agashe, Servant Gives correct relic density for wide range of masses Bold-face particles have zero-modes

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

33
Summary of Exp’t Constraints on M D Anchordoqui, Feng Goldberg, Shapere

Similar presentations

© 2019 SlidePlayer.com Inc.

All rights reserved.

To make this website work, we log user data and share it with processors. To use this website, you must agree to our Privacy Policy, including cookie policy.

Ads by Google