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New Physics Scenarios Jay Wacker SLAC SLAC Summer Institute August 5&6, 2009

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A summer school lecture at the SLAC summer Institute in 2009 on "New Physics Scenarios".

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Page 1: Slac Summer Institute 2009

New Physics Scenarios

Jay WackerSLAC

SLAC Summer InstituteAugust 5&6, 2009

Page 2: Slac Summer Institute 2009

Any minute now!When’s the revolution?

An unprecedented moment

Page 3: Slac Summer Institute 2009

What is a “New Physics Scenario”?

“New Physics”:

A structural change to the Standard Model Lagrangian

“Scenario”:

“A sequence of events especially when imagined”

Page 4: Slac Summer Institute 2009

Why New Physics?Four Paradigms

Page 5: Slac Summer Institute 2009

Why New Physics?Four Paradigms

Experiment doesn’t match theoretical predictionsBest motivation

Page 6: Slac Summer Institute 2009

Why New Physics?Four Paradigms

Experiment doesn’t match theoretical predictionsBest motivation

Parameters are “Unnatural”Well defined and have good theoretical motivation

Page 7: Slac Summer Institute 2009

Why New Physics?Four Paradigms

Experiment doesn’t match theoretical predictionsBest motivation

Parameters are “Unnatural”Well defined and have good theoretical motivation

Reduce/Explain the multitude of parametersTypically has limited success, frequently untestable

Page 8: Slac Summer Institute 2009

Why New Physics?Four Paradigms

Experiment doesn’t match theoretical predictionsBest motivation

Parameters are “Unnatural”Well defined and have good theoretical motivation

Reduce/Explain the multitude of parametersTypically has limited success, frequently untestable

To know what is possibleLet’s us know what we can look for in experiments

Limited only by creativity and taste

Page 9: Slac Summer Institute 2009

The PlanBeyond the SM Physics is 30+ years old

There is no one leading candidate for new physics

New physics models draw upon all corners of the SM

In 2 hours there will be a sketch some principlesused in a half dozen paradigmsthat created hundreds of models

and spawned thousands of papers

Page 10: Slac Summer Institute 2009

Outline

The Standard Model

Motivation for Physics Beyond the SM

Organizing Principles for New Physics

New Physics ScenariosSupersymmetry

Extra DimensionsStrong Dynamics

Page 11: Slac Summer Institute 2009

Standard Model: a story of economysymmetry unification!

15 Particles, 12 Force carriers! 2700 !V !! Couplings

Page 12: Slac Summer Institute 2009

Standard Model: a story of economy

!eL eL eR uL uR dRdLuLuL uRuR dL dL dR dR

symmetry unification!15 Particles, 12 Force carriers! 2700 !V !! Couplings

Page 13: Slac Summer Institute 2009

Standard Model: a story of economy

!eL eL eR uL uR dRdLuLuL uRuR dL dL dR dR

! e q u d

5 Particles 3 Couplings

symmetry unification!15 Particles, 12 Force carriers! 2700 !V !! Couplings

Page 14: Slac Summer Institute 2009

Standard Model: a story of economy

!eL eL eR uL uR dRdLuLuL uRuR dL dL dR dR

! e q u d

5 Particles 3 Couplings

symmetry unification!

4 forces, 20 particles, 20 parameters

x 3

Mystery of Generations:

15 Particles, 12 Force carriers! 2700 !V !! Couplings

Page 15: Slac Summer Institute 2009

The Standard Model... where we stand today

LSM = LGauge + LFermion + LHiggs + LYukawa

Page 16: Slac Summer Institute 2009

The Standard Model... where we stand today

LSM = LGauge + LFermion + LHiggs + LYukawa

LGauge = !14Bµ!

2 ! 14W a

µ!2 ! 1

4GA

µ!2

Page 17: Slac Summer Institute 2009

The Standard Model... where we stand today

LSM = LGauge + LFermion + LHiggs + LYukawa

LGauge = !14Bµ!

2 ! 14W a

µ!2 ! 1

4GA

µ!2

LFermion = QiiD! Qi + U ci iD! U c

i + Dci iD! Dc

i + LiiD! Li + Eci iD! Ec

i

Page 18: Slac Summer Institute 2009

The Standard Model... where we stand today

LSM = LGauge + LFermion + LHiggs + LYukawa

LGauge = !14Bµ!

2 ! 14W a

µ!2 ! 1

4GA

µ!2

LFermion = QiiD! Qi + U ci iD! U c

i + Dci iD! Dc

i + LiiD! Li + Eci iD! Ec

i

LHiggs = |DµH|2 ! !(|H|2 ! v2/2)2

Page 19: Slac Summer Institute 2009

The Standard Model... where we stand today

LSM = LGauge + LFermion + LHiggs + LYukawa

LGauge = !14Bµ!

2 ! 14W a

µ!2 ! 1

4GA

µ!2

LFermion = QiiD! Qi + U ci iD! U c

i + Dci iD! Dc

i + LiiD! Li + Eci iD! Ec

i

LHiggs = |DµH|2 ! !(|H|2 ! v2/2)2

LYuk = yiju QiU

cj H + yij

d QiDcjH

! + yije LiE

cjH

!

Page 20: Slac Summer Institute 2009

Q

U c

Dc

Ec

L

3

331

1

11

1

2

2

+16

!23

+13

!12

+1

Field Color Weak Hypercharge

Standard Model Charges

Page 21: Slac Summer Institute 2009

Motivations for Physics Beyond the Standard Model

The Hierarchy Problem

Dark Matter

Exploration

Page 22: Slac Summer Institute 2009

The Hierarchy ProblemThe SM suffers from a stability crisis

!µ2

!3y2t !2

t

16!2

+34g2!2

W

16!2

+14g!2!2

B

16!2

+!!2

H

16"2

Higgs vev determined by effective mass, not bare massMany contributions that must add up to -(100 GeV)2

=

Page 23: Slac Summer Institute 2009

A recasting of the problem:

Why is gravity so weak?GN

GF= 10!32

Explain how to make GF large (i.e. v small)

Explain why GN is so small (i.e. MPl large)

Page 24: Slac Summer Institute 2009

1998: Large Extra Dimensions (Arkani-Hamed, Dimopoulos, Dvali)

High scale is a “mirage”Gravity is strong at the weak scale

Need to explain how gravity is weakened

MPlanckMWeak

!

2001: Universal Extra Dimensions (Appelquist, Cheng, Dobrescu)

Page 25: Slac Summer Institute 2009

1978: Technicolor(Weinberg, Susskind)

1999: Warped Gravity(Randall, Sundrum)

2001: Little Higgs(Arkani-Hamed, Cohen, Georgi)

The Higgs is composite

h

Resolve substructure at small distances

!M2Composite

Why hadrons are lighter than Planck Scale

Page 26: Slac Summer Institute 2009

A New Symmetryµ2 = 0 not specialUV dynamics at

Page 27: Slac Summer Institute 2009

A New Symmetry

Scalar

Fermion

!

! Supersymmetry

!! "#Scalar Mass related to Fermion Mass

µ2 = 0 not specialUV dynamics at

Page 28: Slac Summer Institute 2009

A New Symmetry

Scalar

Fermion

!

! Supersymmetry

!! "#Scalar Mass related to Fermion Mass

!

Scalar

Scalar

!Shift Symmetry

!! ! + "Scalar Mass forbidden

µ2 = 0 not specialUV dynamics at

Page 29: Slac Summer Institute 2009

A New Symmetry

Scalar

Fermion

!

! Supersymmetry

!! "#Scalar Mass related to Fermion Mass

!

Scalar

Scalar

!Shift Symmetry

!! ! + "Scalar Mass forbidden

1981: Supersymmetric Standard Model(Dimopoulos, Georgi)

2001: Little Higgs(Arkani-Hamed, Cohen, Georgi)

1974: Higgs as Goldstone Boson(Georgi, Pais)

µ2 = 0 not specialUV dynamics at

Page 30: Slac Summer Institute 2009

Dark Matter85% of the mass of the Universe is not described by the SM

There must be physics beyond the Standard Model

Cold dark matterElectrically & Color Neutral

Cold/SlowRelatively small self interactions

Interacts very little with SM particles

No SM particle fits the bill

Page 31: Slac Summer Institute 2009

The WIMP Miracle DM was in equilibrium with SM in the Early Universe

1 3 10 30 100 300 1000!20

!15

!10

!5

0

log

Y(x

)/Y

(x=

0)

x ! m/T

!!Annv"

Incr

easi

ng

Page 32: Slac Summer Institute 2009

The WIMP Miracle DM was in equilibrium with SM in the Early Universe

T ! mDM

1 3 10 30 100 300 1000!20

!15

!10

!5

0

log

Y(x

)/Y

(x=

0)

x ! m/T

!!Annv"

Incr

easi

ng

Page 33: Slac Summer Institute 2009

The WIMP Miracle DM was in equilibrium with SM in the Early Universe

T ! mDM

T ! mDMReverse process energetically disfavored

1 3 10 30 100 300 1000!20

!15

!10

!5

0

log

Y(x

)/Y

(x=

0)

x ! m/T

!!Annv"

Incr

easi

ng

Page 34: Slac Summer Institute 2009

The WIMP Miracle DM was in equilibrium with SM in the Early Universe

T ! mDM

T ! mDMReverse process energetically disfavored

1 3 10 30 100 300 1000!20

!15

!10

!5

0

log

Y(x

)/Y

(x=

0)

x ! m/T

!!Annv"

Incr

easi

ng

Page 35: Slac Summer Institute 2009

The WIMP Miracle DM was in equilibrium with SM in the Early Universe

T ! mDM

T ! mDM

DM too dilute to find each other

T ! mDMReverse process energetically disfavored

1 3 10 30 100 300 1000!20

!15

!10

!5

0

log

Y(x

)/Y

(x=

0)

x ! m/T

!!Annv"

Incr

easi

ng

Page 36: Slac Summer Institute 2009

The WIMP Miracle DM was in equilibrium with SM in the Early Universe

T ! mDM

T ! mDM

DM too dilute to find each other

T ! mDMReverse process energetically disfavored

Relic density is “frozen in”

1 3 10 30 100 300 1000!20

!15

!10

!5

0

log

Y(x

)/Y

(x=

0)

x ! m/T

!!Annv"

Incr

easi

ng

Page 37: Slac Summer Institute 2009

Boltzmann Equation Solves for

! = "DM/"baryon ! 6

Frozen out when nDM !v ! H!ann =

Page 38: Slac Summer Institute 2009

Boltzmann Equation Solves for

! = "DM/"baryon ! 6

Frozen out when nDM !v ! H!ann =

H ! T 2/MPlnDM = !

mp

mDM"s

s ! T 3 TFO ! mDM

Page 39: Slac Summer Institute 2009

Boltzmann Equation Solves for

! = "DM/"baryon ! 6

!v =1

"mpMPl#! 3" 10!26cm3/s

Frozen out when nDM !v ! H!ann =

H ! T 2/MPlnDM = !

mp

mDM"s

s ! T 3 TFO ! mDM

Page 40: Slac Summer Institute 2009

Boltzmann Equation Solves for

! = "DM/"baryon ! 6

!v =1

"mpMPl#! 3" 10!26cm3/s

Frozen out when

mDM ! !" 20 TeV! ! "2

m2DM

=!

nDM !v ! H!ann =

H ! T 2/MPlnDM = !

mp

mDM"s

s ! T 3 TFO ! mDM

Page 41: Slac Summer Institute 2009

We want to see what’s there!

Muon, Strange particles, Tau leptonnot predicted before discovery

Serendipity favors the prepared!

Exploration

Page 42: Slac Summer Institute 2009

Chirality

Anomaly Cancellation

Flavor Symmetries

Gauge Coupling Unification

Effective Field Theory

Organizing Principlesfor going beyond the SM

Page 43: Slac Summer Institute 2009

ChiralityA symmetry acting a fermions that forbids masses

! =!

ffc

"M!! = M(ff c + f fc)

Page 44: Slac Summer Institute 2009

ChiralityA symmetry acting a fermions that forbids masses

! =!

ffc

"M!! = M(ff c + f fc)

f ! ei!f fc ! ei!c

fc

Can do independent phase rotations

Page 45: Slac Summer Institute 2009

ChiralityA symmetry acting a fermions that forbids masses

! =!

ffc

"M!! = M(ff c + f fc)

! = !!cVector symmetry

Allows mass

JµV = !!µ!

f ! ei!f fc ! ei!c

fc

Can do independent phase rotations

Page 46: Slac Summer Institute 2009

ChiralityA symmetry acting a fermions that forbids masses

! =!

ffc

"M!! = M(ff c + f fc)

! = !!cVector symmetry

Allows mass

JµV = !!µ!

! = !cAxial symmetry

Forbids mass

JµA = !!5!

µ!

f ! ei!f fc ! ei!c

fc

Can do independent phase rotations

Page 47: Slac Summer Institute 2009

The Standard Model is a Gauged Chiral Theory

All masses are forbidden by a gauge symmetry

15 different bilinears all forbidden

QU c ! (1, 2)! 12 QEc ! (3, 2) 7

6

DcEc ! (3, 1) 43

U cL ! (3, 2)! 53

EcEc ! (1, 1)+2

LL ! (1, 1)!1QQ ! (3, 3) 1

3

DcDc ! (3, 1) 23

DcL ! (3, 2)! 16

etc...

The Standard Model force carriers forbid fermion masses

Page 48: Slac Summer Institute 2009

Electroweak Symmetry BreakingBreaking of Chiral Symmetry

SU(2)L ! U(1)Y " U(1)EM!H" #!

0v

"V (H) = !|H|4 ! µ2|H|2

LYuk = yiju QiU

cj H + yij

d QiDcjH

! + yije LiE

cjH

!

Q =!

UD

"L =

!!E

"

LYuk = miju UiU

cj + mij

d DiDcj + mij

e EiEcj

Fermions pick up Dirac Masses

Page 49: Slac Summer Institute 2009

Effective Field Theory

Take a theory with light and heavy particlesLFull = Llight(!) + Lheavy(!,!)

If we only can ask questions in the range!

s" !cut o!<#M"

!cut o!

!s

m!

M!

Page 50: Slac Summer Institute 2009

Effective Field Theory

Take a theory with light and heavy particlesLFull = Llight(!) + Lheavy(!,!)

If we only can ask questions in the range!

s" !cut o!<#M"

!cut o!

!s

m!

M!

with n > 0

Dynamics of light fields described by

Lfull(!) = Llight(!) + "L(!) !L ! O(")/!ncut o!

Only contribute as !" !! "

s

!cut o!

"n

known as “irrelevant operators”

Nonrenomalizable

Page 51: Slac Summer Institute 2009

We have only tested the SM to certain precision

How do we know that there aren’t those effects?

We know the SM isn’t the final theory of nature

We should view any theory we test asan “Effective Theory” that describes the dynamics

Shouldn’t be constrained by renormalizability

One way of looking for new physics is bylooking for these nonrenormalizable operators

Page 52: Slac Summer Institute 2009

Limits on Non-Renormalizable Operators

Page 53: Slac Summer Institute 2009

Limits on Non-Renormalizable Operators

Baryon Number Violation QQQL/!2

! >! 1016 GeV

Page 54: Slac Summer Institute 2009

Limits on Non-Renormalizable Operators

Baryon Number Violation QQQL/!2

! >! 1016 GeV

Lepton Number Violation (LH)2/!! ! 1015 GeV

Page 55: Slac Summer Institute 2009

Limits on Non-Renormalizable Operators

Baryon Number Violation QQQL/!2

! >! 1016 GeV

Lepton Number Violation (LH)2/!! ! 1015 GeV

Flavor Violation H†(L2!µ!Ec

1)Bµ!/!2Dc

1Dc1D

c2D

c2/!2

! >! 106 GeV ! >! 106 GeV

Page 56: Slac Summer Institute 2009

Limits on Non-Renormalizable Operators

Baryon Number Violation QQQL/!2

! >! 1016 GeV

Lepton Number Violation (LH)2/!! ! 1015 GeV

Flavor Violation H†(L2!µ!Ec

1)Bµ!/!2Dc

1Dc1D

c2D

c2/!2

! >! 106 GeV ! >! 106 GeV

CP Violation iH†(L1!µ!Ec

1)Bµ!/!2

! >! 106 GeV

Page 57: Slac Summer Institute 2009

Limits on Non-Renormalizable Operators

Baryon Number Violation QQQL/!2

! >! 1016 GeV

Lepton Number Violation (LH)2/!! ! 1015 GeV

Flavor Violation H†(L2!µ!Ec

1)Bµ!/!2Dc

1Dc1D

c2D

c2/!2

! >! 106 GeV ! >! 106 GeV

CP Violation iH†(L1!µ!Ec

1)Bµ!/!2

! >! 106 GeVPrecision Electroweak |H†DµH|2/!2

! >! 3" 103 GeV

Page 58: Slac Summer Institute 2009

Limits on Non-Renormalizable Operators

Baryon Number Violation QQQL/!2

! >! 1016 GeV

Lepton Number Violation (LH)2/!! ! 1015 GeV

Flavor Violation H†(L2!µ!Ec

1)Bµ!/!2Dc

1Dc1D

c2D

c2/!2

! >! 106 GeV ! >! 106 GeV

CP Violation iH†(L1!µ!Ec

1)Bµ!/!2

! >! 106 GeVPrecision Electroweak |H†DµH|2/!2

! >! 3" 103 GeV

Contact Operators (L1L1)2/!2

! >! 3" 103 GeV

Page 59: Slac Summer Institute 2009

Limits on Non-Renormalizable Operators

Baryon Number Violation QQQL/!2

! >! 1016 GeV

Lepton Number Violation (LH)2/!! ! 1015 GeV

Flavor Violation H†(L2!µ!Ec

1)Bµ!/!2Dc

1Dc1D

c2D

c2/!2

! >! 106 GeV ! >! 106 GeV

CP Violation iH†(L1!µ!Ec

1)Bµ!/!2

! >! 106 GeVPrecision Electroweak |H†DµH|2/!2

! >! 3" 103 GeV

Contact Operators (L1L1)2/!2

! >! 3" 103 GeV

Generic Operators Gµ!G!"Gµ"/!2

! >! 3" 102 GeV

Page 60: Slac Summer Institute 2009

Flavor SymmetriesSymmetries that interchange fermions

Turn off all the interactions of the SM = Free Theory

L = !i i"! !i !i ! U ji !j U(N) symmetry

Page 61: Slac Summer Institute 2009

Flavor SymmetriesSymmetries that interchange fermions

Turn off all the interactions of the SM = Free Theory

Q,U c, Dc, L,Ec = 15 Fermions/Generation

45 Total fermions that look the same in the free theoryglobal symmetry! U(45)

L = !i i"! !i !i ! U ji !j U(N) symmetry

Page 62: Slac Summer Institute 2009

Flavor SymmetriesSymmetries that interchange fermions

Turn off all the interactions of the SM = Free Theory

Q,U c, Dc, L,Ec = 15 Fermions/Generation

45 Total fermions that look the same in the free theoryglobal symmetry! U(45)

Gauge interactions destroy most of this symmetry

U(3)5 = U(3)Q ! U(3)Uc ! U(3)Dc ! U(3)L ! U(3)Ec

Yukawa couplings break the rest...but they are the only source of U(3)5 breaking

L = !i i"! !i !i ! U ji !j U(N) symmetry

Page 63: Slac Summer Institute 2009

Prevents Flavor Changing Neutral CurrentsImagine two scalars with two sources of flavor breaking

LYuk = yijH!i!cj + "ij#!i!

cj

H = v + h mij = yijv

Page 64: Slac Summer Institute 2009

Prevents Flavor Changing Neutral CurrentsImagine two scalars with two sources of flavor breaking

LYuk = yijH!i!cj + "ij#!i!

cj

H = v + h mij = yijv

Can diagonalize mass matrix with unitary transformations!i ! U j

i !j !ci ! V j

i !cj mij ! (UT mV )ij = Mi!

ij

LYuk !Mi!ij"i"

cj(1 + h/v) + (UT #V )ij$"i"j

Page 65: Slac Summer Institute 2009

Prevents Flavor Changing Neutral CurrentsImagine two scalars with two sources of flavor breaking

LYuk = yijH!i!cj + "ij#!i!

cj

H = v + h mij = yijv

Higgs doesn’t change flavor, but other scalar field is a disaster

K0K0

d s

sd

!

! ! yUnless m!

!>! 100 TeVor

Can diagonalize mass matrix with unitary transformations!i ! U j

i !j !ci ! V j

i !cj mij ! (UT mV )ij = Mi!

ij

LYuk !Mi!ij"i"

cj(1 + h/v) + (UT #V )ij$"i"j

Page 66: Slac Summer Institute 2009

Anomaly CancellationQuantum violation of current conservation

!µJaµ ! Tr T aT bT c (F bF c)

T a

T b

T c

!

An anomaly leads to a mass for a gauge boson

m2 =!

g2

16!2

"3

!2

Page 67: Slac Summer Institute 2009

Anomaly cancellation:

One easy way: only vector-like gauge couplings

!, !c

(+1)3 + (!1)3 = 0

Page 68: Slac Summer Institute 2009

Anomaly cancellation:

but the Standard Model is chiral

One easy way: only vector-like gauge couplings

!, !c

(+1)3 + (!1)3 = 0

Page 69: Slac Summer Institute 2009

Anomaly cancellation:

but the Standard Model is chiral

One easy way: only vector-like gauge couplings

!, !c

(+1)3 + (!1)3 = 0

SU(3)SU(3)

SU(3)

U(1)U(1)

U(1)

U(1)SU(3)

SU(3)

6!

16

"3

+ 3!!2

3

"3

+ 3!

13

"3

+ 2!!1

2

"3

+ (1)3 = 0

2(1)3 + (!1)3 + (!1)3 + 0 + 0 = 0

2!

16

"+

!!2

3

"+

!13

"+ 0 + 0 = 0

Q U c Dc L Ec

It works, but is a big constraint!

Page 70: Slac Summer Institute 2009

Gauge coupling unification: Our Microscope

!!1

E103 106 109 1012 1015

(GeV)

30

40

20

10

sin2 !w

1

2

3

EGUT

d

dt!!1 =

b0

2"Counts charged matter

Page 71: Slac Summer Institute 2009

Gauge coupling unification: Our Microscope

!!1

E103 106 109 1012 1015

(GeV)

30

40

20

10

sin2 !w

1

2

3

EGUT

!!13 (t) = !!1

3 (t") +b3 0

2"(t! t")

!!12 (t) = !!1

2 (t") +b2 0

2"(t! t")

!!11 (t) = !!1

1 (t") +b1 0

2"(t! t")

d

dt!!1 =

b0

2"Counts charged matter

Page 72: Slac Summer Institute 2009

Gauge coupling unification: Our Microscope

!!1

E103 106 109 1012 1015

(GeV)

30

40

20

10

sin2 !w

1

2

3

EGUT

!!13 (t) = !!1

3 (t") +b3 0

2"(t! t")

!!12 (t) = !!1

2 (t") +b2 0

2"(t! t")

!!11 (t) = !!1

1 (t") +b1 0

2"(t! t")

d

dt!!1 =

b0

2"Counts charged matter

A3221 = 0.714

!!13 (t)! !!1

2 (t)!!1

2 (t)! !!11 (t)

=b3 0 ! b2 0

b2 0 ! b1 0

Weak scale measurementHigh scale particle contentB32

21 = 0.528

Page 73: Slac Summer Institute 2009

!eL eL eR uL uR dRdLuLuL uRuR dL dL dR dR

Grand Unification

! e q u d SU(3)! SU(2)! U(1)

Gauge coupling unification indicates forces arise from single entity

Page 74: Slac Summer Institute 2009

!eL eL eR uL uR dRdLuLuL uRuR dL dL dR dR

Grand Unification

! e q u d

5 10 SU(5)

SU(3)! SU(2)! U(1)

Gauge coupling unification indicates forces arise from single entity

Page 75: Slac Summer Institute 2009

!eL eL eR uL uR dRdLuLuL uRuR dL dL dR dR

Grand Unification

! e q u d

5 10 SU(5)

!eR

! SO(10)

SU(3)! SU(2)! U(1)

Gauge coupling unification indicates forces arise from single entity

Page 76: Slac Summer Institute 2009

Standard Model Summary

The Standard Model is chiral gauge theory

It is an effective field theory

It is anomaly free & anomaly cancellationrestricts new charged particles

Making sure that there is no new sourcesof flavor violation ensures that new theories are

not horribly excluded

SM Fermions fit into GUT multiplets,but gauge coupling unification doesn’t quite work

Page 77: Slac Summer Institute 2009

The Scenarios

Supersymmetry

Little Higgs Theories

Extra Dimensions

Technicolor

Page 78: Slac Summer Institute 2009

SupersymmetryDoubles Standard Model particles

Q,U c, Dc, L,Ec

Q, U c, Dc, L, Ec

H

Hu,Hd

Hu, Hd

g,W,B

g, W , B

Dirac pair of Higgsinos GauginosSfermions

Squarks, Sleptons Gluino, Wino, Bino

Fermions Higgs Gauge

(1, 2) 12

(1, 2)! 12

Susy Taxonomy

Needed for anomaly cancellation

Page 79: Slac Summer Institute 2009

Susy Gauge Coupling Unification

A3221 = 0.714

!!13 (t)! !!1

2 (t)!!1

2 (t)! !!11 (t)

=b3 0 ! b2 0

b2 0 ! b1 0

B3221 =

4285

= 0.714

Too good!(Two loop beta functions, etc)

But significantly better than SM or any other BSM theory

Only need to add in particles that contribute to the relative runningGauge Bosons, Gauginos, Higgs & Higgsinos

Page 80: Slac Summer Institute 2009

SUSY Interactions

Rule of thumb: take 2 and flip spins

q

qq

q

gg

Q

U c

U c

HH

Q

Page 81: Slac Summer Institute 2009

SUSY BreakingSUSY is not an exact symmetry

We don’t know how SUSY is broken, butSUSY breaking effects can be parameterized in the Lagrangian

Lsoft = Lm20+ Lm 1

2+ LA + LB

Page 82: Slac Summer Institute 2009

SUSY BreakingSUSY is not an exact symmetry

We don’t know how SUSY is broken, butSUSY breaking effects can be parameterized in the Lagrangian

Lsoft = Lm20+ Lm 1

2+ LA + LB

Lm20

= m2!

ij !†

i !j

+m2Hu

|Hu|2 + m2Hd

|Hd|2! ! Q,U c, Dc, L,Ec

Page 83: Slac Summer Institute 2009

SUSY BreakingSUSY is not an exact symmetry

We don’t know how SUSY is broken, butSUSY breaking effects can be parameterized in the Lagrangian

Lsoft = Lm20+ Lm 1

2+ LA + LB

Lm 12

= m1BB + m2WW + m3gg

Lm20

= m2!

ij !†

i !j

+m2Hu

|Hu|2 + m2Hd

|Hd|2! ! Q,U c, Dc, L,Ec

Page 84: Slac Summer Institute 2009

SUSY BreakingSUSY is not an exact symmetry

We don’t know how SUSY is broken, butSUSY breaking effects can be parameterized in the Lagrangian

Lsoft = Lm20+ Lm 1

2+ LA + LB

Lm 12

= m1BB + m2WW + m3gg

LA = aiju QiU

cj Hu + aij

d QiDcjHd + aij

e LiEcjHd

Lm20

= m2!

ij !†

i !j

+m2Hu

|Hu|2 + m2Hd

|Hd|2! ! Q,U c, Dc, L,Ec

Page 85: Slac Summer Institute 2009

SUSY BreakingSUSY is not an exact symmetry

We don’t know how SUSY is broken, butSUSY breaking effects can be parameterized in the Lagrangian

Lsoft = Lm20+ Lm 1

2+ LA + LB

Lm 12

= m1BB + m2WW + m3gg

LA = aiju QiU

cj Hu + aij

d QiDcjHd + aij

e LiEcjHd

LB = Bµ HuHd

Lm20

= m2!

ij !†

i !j

+m2Hu

|Hu|2 + m2Hd

|Hd|2! ! Q,U c, Dc, L,Ec

Page 86: Slac Summer Institute 2009

Problem with Parameterized SUSY Breaking

There are over 100 parameters onceSupersymmetry no longer constrains interactions

Most of these are new flavor violation parametersor CP violating phases

Horribly excluded

Susy breaking is not generic!

m2ijQ

†i Q

j Qi ! U ji Qj

gs g Q†iQ

i ! gs g Q†i (U

†U)ijQ

j

Page 87: Slac Summer Institute 2009

Soft Susy Breaking

i.e. Super-GIM mechanismUniversality of soft terms

d

d s

s

g gd, s, b

d, s, b

K0 K0

Page 88: Slac Summer Institute 2009

Soft Susy Breaking

i.e. Super-GIM mechanismUniversality of soft terms

d

d s

s

g gd, s, b

d, s, b

K0 K0

Need to be Flavor Universal Couplings

A ! 11m2

0 ! 11Scalar MassesTrilinear A-Terms

Approximate degeneracy of scalars

Page 89: Slac Summer Institute 2009

Proton StabilityNew particles ⇒ new ways to mediate proton decay

Dangerous couplings

Prot

on Pionu u

u

d

d

u

e+

LRPV = !BU cDcDc + !LQLDc

Supersymmetric couplings that violate SM symmetries

A new symmetry forbids these couplings: (!1)3B+L+2s

Page 90: Slac Summer Institute 2009

Proton StabilityNew particles ⇒ new ways to mediate proton decay

Lightest Supersymmetric Particle is stable

Dangerous couplings

Prot

on Pionu u

u

d

d

u

e+

LRPV = !BU cDcDc + !LQLDc

Supersymmetric couplings that violate SM symmetries

A new symmetry forbids these couplings: (!1)3B+L+2s

Page 91: Slac Summer Institute 2009

Proton StabilityNew particles ⇒ new ways to mediate proton decay

Lightest Supersymmetric Particle is stable

Dangerous couplings

Must be neutral and colorless -- Dark Matter

Prot

on Pionu u

u

d

d

u

e+

LRPV = !BU cDcDc + !LQLDc

Supersymmetric couplings that violate SM symmetries

A new symmetry forbids these couplings: (!1)3B+L+2s

Page 92: Slac Summer Institute 2009

Mediation of Susy Breaking

MSSM PrimoridalSusy BreakingMediation

Susy breaking doesn’t occur inside the MSSMFelt through interactions of intermediate particles

Studied to reduce the number of parametersGauge Mediation

Universal “Gravity” MediationAnomaly Mediation

Usually only 4 or 5 parameters...but for phenomenology, these are too restrictive

Page 93: Slac Summer Institute 2009

The Phenomenological MSSMThe set of parameters that are:

Not strongly constrainedEasily visible at colliders

First 2 generation sfermions are degenerate

3rd generation sfermions in independent

Gaugino masses are free

Independent A-terms proportional to Yukawas

Higgs Masses are Free

55334

20 Total Parameters

Page 94: Slac Summer Institute 2009

Charginos & NeutralinosThe Higgsinos, Winos and Binos

Hu ! 2 12" 0,+1 Hd ! 2! 1

2" 0,#1 W ! 30 " 0,+1,#1 B ! 10 " 0

After EWSB: 2 Charge +1 Dirac Fermions

4 Charge 0 Majorana Fermions

L = µHuHd + m2WW + m1BB

+(H†uHu + H†

dHd)(gW + g!B)

(2)

All mix together, but typically mixture is small

Tend find charginos next to their neutralino brethren

Neutralinos are good DM candidates

Page 95: Slac Summer Institute 2009

Elementary Phenomenology

Neutralinos Charginos Sleptons Squarks Gluinos

Mas

s

Page 96: Slac Summer Institute 2009

Collider signatures

q

q

!0

!0

!02

!+1

!

!!

!

!

!

Trileptons+MET: If sleptons are availableN

eutra

linos

Cha

rgin

os

Slep

tons

Mas

s

3 Leptons + MET

Page 97: Slac Summer Institute 2009

Collider signatures

9 RESULTS AND LIMITS 13

)2Chargino Mass (GeV/c100 110 120 130 140 150 160 170

3l)

(p

b)

!± 1"#

0 2" ~

BR

($

%

0

0.2

0.4

0.6

0.8

1

1.2

-1CDF Run II Preliminary, 3.2 fb

)2Chargino Mass (GeV/c

LEP 2 direct

limit

BR$ NLO

%Theory

% 1 ±Expected Limit % 2 ±Expected Limit

95% CL Upper Limit: expected

Observed Limit

) > 0µ=0, (0

=3, A&=60, tan 0

mSugra M

Figure 6: Expected and observed limit for the mSugra model M0 =60, tan! = 3, A0 = 0, (µ) > 0. In red is the theoretical " ! BR and inblack is our expected limit with one and two " errors. We expect to set alimit of about 156 GeV/c2, and observe a limit of 164 GeV/c2.

q

q

!0

!0

!02

!+1

!

!!

!

!

!

Trileptons+MET: If sleptons are availableN

eutra

linos

Cha

rgin

os

Slep

tons

Mas

s

3 Leptons + MET

Page 98: Slac Summer Institute 2009

Collider signaturesTrileptons+MET

Without sleptons in the decay chainN

eutra

linos

Cha

rgin

os

Slep

tons

Mas

s q

q

!0

!0

!02

!+1 !

!!!W+

Z0

30% leptonic Br of W, 10% leptonic Br of Z3% Total Branching Rate

Page 99: Slac Summer Institute 2009

7

Cro

ss S

ecti

on [p

b]

]2 [GeV/cg~

M]2 [GeV/cq~

M

2 = 230 GeV/cg~

M

q~ = M

g~M

2 = 370 GeV/cq~

M

2 = 460 GeV/cq~

M

Theoretical uncertainties not included in the calculation of the limit

<0µ = 5, ! = 0, tan0A -1L = 2.0 fb

NLO Prospino Ren.)"syst. uncert. (PDF

expected limit 95% C.L.

observed limit 95% C.L.

-110

1

10

210

-110

1

10

210

300 400 500

-210

-110

1

10

300 400 500

-210

-110

1

10

200 300 400 500200 300 400 500

FIG. 2: Observed (solid lines) and expected (dashed lines)95% C.L. upper limits on the inclusive squark and gluinoproduction cross sections as a function of M!q (left) and

M!g (right) in di!erent regions of the squark-gluino mass

plane, compared to NLO mSUGRA predictions (dashed-dotted lines). The shaded bands denote the total uncertaintyon the theory.

0 100 200 300 400 500 6000

100

200

300

400

500

600

no mSUGRA

solution

LEP

UA

1

UA

2

g~

= M

q~M

0 100 200 300 400 500 6000

100

200

300

400

500

600

observed limit 95% C.L.

expected limit

FNAL Run I

)-1

<0 (L=2.0fbµ=5, !=0, tan0A

]2

[GeV/cg~M

]2 [G

eV/c

q~M

FIG. 3: Exclusion plane at 95 % C.L. as a function of squarkand gluino masses in an mSUGRA scenario with A0 = 0,µ < 0 and tan! = 5. The observed (solid line) and expected(dashed line) upper limits are compared to previous resultsfrom SPS [30] and LEP [31] experiments at CERN (shadedbands), and from the Run I at the Tevatron [2] (dashed-dottedline). The hatched area indicates the region in the plane withno mSUGRA solution.

Japan; the Natural Sciences and Engineering ResearchCouncil of Canada; the National Science Council of theRepublic of China; the Swiss National Science Founda-tion; the A.P. Sloan Foundation; the Bundesministeriumfur Bildung und Forschung, Germany; the Korean Sci-ence and Engineering Foundation and the Korean Re-search Foundation; the Science and Technology FacilitiesCouncil and the Royal Society, UK; the Institut Nationalde Physique Nucleaire et Physique des Particules/CNRS;the Russian Foundation for Basic Research; the Ministe-rio de Ciencia e Innovacion, and Programa Consolider-Ingenio 2010, Spain; the Slovak R&D Agency; and the

Academy of Finland.

[1] H. E. Haber and G. L. Kane, Phys. Rep. 117, 75 (1985).[2] T. A!older et al. (CDF Collaboration), Phys. Rev. Lett.

88, 041801 (2002); S. Abachi et al. (D0 Collaboration),ibid. 75, 618 (1995).

[3] V.M. Abazov et al. (D0 Collaboration), Phys. Lett. B660, 449 (2008).

[4] H. P. Nilles, Phys. Rep. 110, 1 (1984).[5] CDF uses a cylindrical coordinate system about the beam

axis with polar angle " and azimuthal angle #. We definetransverse energy ET = E sin", transverse momentumpT = p sin", pseudorapidity $ = !ln(tan( !

2 )), and rapid-

ity y = 12 ln(E+pz

E!pz

). The missing transverse energy E/T is

defined as the norm of !"

iEi

·%ni, where %ni is the com-ponent in the azimuthal plane of the unit vector pointingfrom the interaction point to the i-th calorimeter tower.

[6] D. Acosta et al. (CDF Collaboration), Phys. Rev. D 71,032001 (2005).

[7] D. Acosta et al., Nucl. Instrum. Methods, A 494, 57(2002).

[8] T. Sjostrand et al., Comp. Phys. Comm. 135, 238 (2001).[9] T. A!older et al. (CDF Collaboration), Phys. Rev. D 65,

092002 (2002).[10] M. Cacciari et al., J. High Energy Phys. 0404, 068

(2004).[11] J. M.Campbell and R. K. Ellis, Phys. Rev. D60, 113006

(1999).[12] M.L. Mangano et al., J. High Energy Phys. 07, 001

(2003).[13] A Abulencia et al. (CDF Collaboration), J. Phys. G:

Nucl. Part. Phys. 34, 2457 (2007).[14] F. Maltoni and T. Stelzer, J. High Energy Phys. 02, 027

(2003).[15] B. W. Harris et al., Phys. Rev. D66, 054024 (2002).[16] B. C. Allanach et al., Eur. Phys. J. C25, 113 (2002).[17] W. Beenakker et al., Nucl. Phys. B492, 51 (1997).[18] F. Paige and S. Protopopescu, in Supercollider Physics,

p. 41, ed. D. Soper (World Scientific, 1986).[19] J. Pumplin et al., J. High Energy Phys. 0207, 012 (2002).[20] Pole masses are considered. The squark mass is averaged

over the first two squark generations.[21] R. Brun et al., Tech. Rep. CERN-DD/EE/84-1, 1987.[22] G. Grindhammer, M. Rudowicz, and S. Peters, Nucl. In-

strum. Methods A 290, 469 (1990).[23] F. Abe et al. (CDF Collaboration), Phys. Rev. D 45,

1448 (1992).[24] A. Bhatti et al., Nucl. Instrum. Methods A 566, 375

(2006).[25] Charge conjugation is implied throughout the paper.[26] The sum runs over the selected jets. In the four-jets case,

the first three leading jets are considered.[27] X. Portell, Ph.D. Thesis, U.A.B., Barcelona (2007).[28] G. De Lorenzo, Master Thesis, U.A.B., Barcelona (2008).[29] R. Cousins, Am. J. Phys. 63, 398 (1995).[30] C. Albajar et al. (UA1 Collaboration), Phys. Lett. B198,

261 (1987); J. Alitti et al. (UA2 Collaboration), ibid.B235, 363 (1990).

[31] LEPSUSYWG/02-06.2, http://lepsusy.web.cern.ch/lepsusy/.

Collider signaturesGluino Pairs: 4j +MET Squark Pairs: 2j +MET Squark-Gluino Pairs: 3j +MET

q

q

g

g

q

q

q

q

!0

!0

q

q

q

q

q q

!0

!0

q

q

q

qq gq

g

!0

!0

q

qq

mSUGRA Searchm3 : m2 : m1 = 6 : 2 : 1

Page 100: Slac Summer Institute 2009

Away from mSUGRA Gluino Search

Out[27]=

XX

100 200 300 400 5000

50

100

150

Gluino Mass !GeV"

BinoMass!GeV

"mg ! 130 GeVmg ! 120 GeV

g ! qqB

g ! qqW ! qqBW

Page 101: Slac Summer Institute 2009

The Higgs Mass ProblemVHiggs = !|H|4 + µ2|H|2m2

h0 = 2!v2 = !2µ2

Page 102: Slac Summer Institute 2009

The Higgs Mass ProblemVHiggs = !|H|4 + µ2|H|2m2

h0 = 2!v2 = !2µ2

mh0 !MZ0!susy =18

!g2 + g!2" cos2 2"

Need a susy copy of quartic coupling, only gauge coupling works in MSSM

Page 103: Slac Summer Institute 2009

The Higgs Mass Problemm2

h0 = 2!v2 = !2µ2

H

t t

H

!" =3y4

top

8#2log

mstop

mtop

mh0 !MZ0!susy =18

!g2 + g!2" cos2 2"

Need a susy copy of quartic coupling, only gauge coupling works in MSSM

Page 104: Slac Summer Institute 2009

The Higgs Mass Problem

!µ2 = !3y2

top

8"2m2

stopH t tH

m2h0 = 2!v2 = !2µ2

H

t t

H

!" =3y4

top

8#2log

mstop

mtop

mh0 !MZ0!susy =18

!g2 + g!2" cos2 2"

Need a susy copy of quartic coupling, only gauge coupling works in MSSM

Page 105: Slac Summer Institute 2009

The Higgs Mass Problem

!µ2 = !3y2

top

8"2m2

stopH t tH

Higgs mass gain is only logFine tuning loss is quadratic

Difficult to make the Higgs heavier than 125 GeV in MSSM

FT !m2

h0

!µ2

m2h0 = 2!v2 = !2µ2

H

t t

H

!" =3y4

top

8#2log

mstop

mtop

mh0 !MZ0!susy =18

!g2 + g!2" cos2 2"

Need a susy copy of quartic coupling, only gauge coupling works in MSSM

Page 106: Slac Summer Institute 2009

Susy is the leading candidate for BSM Physics

Dark Matter candidate

Gauge Coupling Unification

Compelling structure

Become the standard lamppost

Basic Susy Signatures away from mSUGRAare still being explored

A lot of the qualitative signatures of Susyappear in other models

Page 107: Slac Summer Institute 2009

Extra Dimensions Taxonomy

Large TeV Small

Flat Curved

UEDs RS Models GUT ModelsADD Models

Page 108: Slac Summer Institute 2009

Kaluza-Klein ModesThe general method to analyze higher dimensional theories

S =!

d4x

!dy |!M"(x, y)|2 !M2|"(x, y)|2

y

Page 109: Slac Summer Institute 2009

Kaluza-Klein ModesThe general method to analyze higher dimensional theories

S =!

d4x

!dy |!M"(x, y)|2 !M2|"(x, y)|2

y

(!µ!µ ! !25 + M2)"(x, y) = 0

Equations of Motion

Page 110: Slac Summer Institute 2009

Kaluza-Klein ModesThe general method to analyze higher dimensional theories

S =!

d4x

!dy |!M"(x, y)|2 !M2|"(x, y)|2

y

(!µ!µ ! !25 + M2)"(x, y) = 0

Equations of Motion

!(x, y) =!

n

!n(x)fn(y)!

!µ!µ + M2 +"

2"n

R

#2$

#n(x) = 0

One 5D field = tower of 4D fields

fn(y) =e2!iny/R

!2!R

Page 111: Slac Summer Institute 2009

Large Extra Dimensions

GravitySM

Integrate out extra dimension

S4+n =!

d4x

!dny!

g M2+n! R4+n + !n(y)LSM

S4 e! =!

d4x!

g M4+n! Ln R4 + LSM

Page 112: Slac Summer Institute 2009

Large Extra Dimensions

GravitySM

Integrate out extra dimension

S4+n =!

d4x

!dny!

g M2+n! R4+n + !n(y)LSM

S4 e! =!

d4x!

g M4+n! Ln R4 + LSM

M2Pl = M2+n

! Ln

Identify new Planck Mass

Page 113: Slac Summer Institute 2009

Large Extra Dimensions

GravitySM

Integrate out extra dimension

S4+n =!

d4x

!dny!

g M2+n! R4+n + !n(y)LSM

S4 e! =!

d4x!

g M4+n! Ln R4 + LSM

M2Pl = M2+n

! Ln

Identify new Planck Massn L1 1010 km

2 1 mm

3 10nm

4 10-2nm

5 100fm

6 1fmM! ! 1 TeVSet

If fundamental Planck mass is weakscale, there is no hierarchy problem!

Page 114: Slac Summer Institute 2009

Large Extra Dimension Signatures

Monophoton+MET

6

Background EventsZ ! !! 388 ± 30W ! "! 187 ± 14W ! µ! 117 ± 9W ! e! 58 ± 4Z ! ## 8 ± 1

Multi-jet 23 ± 20$+jet 17 ± 5

Non-collision 10 ± 10Total predicted 808 ± 62Data observed 809

TABLE II: Number of observed events and expected SM back-grounds in the jet + E/T candidate sample.

mates and the number of observed events are shown inTable II, and a comparison of the expected and observedleading jet ET distributions is shown in Fig. 2.

(GeV)TLeading Jet E100 150 200 250 300 350 400

Eve

nts

/ 1

0 G

eV

0

50

100

150

200

250

300

Data

SM Prediction

=1TeV)DSM + LED (n=2,M

)-1

CDF II ( 1.1 fb

FIG. 2: Predicted and observed leading jet ET distributionsfor the jet + E/T candidate sample. The expected LED signalcontribution for the case of n = 2 and MD = 1.0 TeV is alsoshown.

Based on the observed agreement with the SM expecta-tion in both the ! + E/T and jet + E/T candidate samples,we proceed to set lower limits on MD for the LED model.The limits are obtained solely from the total number ofobserved events in each of the samples (no kinematicshape information is incorporated). In order to estimateour sensitivity to the ADD model we simulate expectedsignals in both final states using the pythia [12] eventgenerator in conjunction with a geant [13] based de-tector simulation. For each extra dimension scenario wesimulate event samples for MD ranging between 0.7 and2 TeV. In the case of the ! + E/T analysis, the final kine-matic selection requirements for the candidate sampleare determined by optimizing the expected cross sectionlimit without looking at the data. The jet + E/T anal-ysis was done as a generic search for new physics usingthree sets of kinematic cuts, the most sensitive of which isused here. To compute the expected 95% C.L. cross sec-tion upper limits we combine the predicted ADD signal

$ + E/T Jet + E/T Combinedn % Mobs

D % MobsD Mobs

D

2 7.2 1080 9.9 1310 14003 7.2 1000 11.1 1080 11504 7.6 970 12.6 980 10405 7.3 930 12.1 910 9806 7.2 900 12.3 880 940

TABLE III: Percentage of signal events passing the candidatesample selection criteria (%) and observed 95% C.L. lowerlimits on the e!ective Planck scale in the ADD model (Mobs

D )in GeV/c2 as a function of the number of extra dimensions inthe model (n) for both individual and the combined analysis.

Number of Extra Dimensions2 3 4 5 6

Lo

we

r L

imit (

Te

V)

DM

0.6

0.8

1

1.2

1.4

1.6

Number of Extra Dimensions2 3 4 5 6

Lo

we

r L

imit (

Te

V)

DM

0.6

0.8

1

1.2

1.4

1.6

TE + !CDF II Jet/

)-1

(2.0 fbTE + !CDF II

)-1

(1.1 fbTECDF II Jet +

LEP Combined

FIG. 3: 95 % C.L. lower limits on MD in the ADD model asa function of the number of extra dimensions in the model.

and background estimates with systematic uncertaintieson the acceptance using a Bayesian method with a flatprior [14]. The acceptance is found to be almost indepen-dent (within 2%) of the mass MD. The total systematicuncertainties on the number of expected signal events are5.7% and 12.4% for the ! + E/T and jet + E/T candidatesamples respectively. The largest systematic uncertain-ties arise from modeling of initial/final state radiationconvoluted with jet veto requirements, choice of renor-malization and factorization scales, modeling of partondistribution functions, modeling of the jet energy scale(jet + E/T sample only), and the luminosity measurement.

Since the underlying graviton production mechanismis equivalent for both final states, the combination of theindependent limits obtained from the two candidate sam-ples is based on the predicted relative contributions ofthe four graviton production processes. Systematic un-certainties on the signal acceptances are treated as 100%correlated, while uncertainties on background estimates,obtained in most cases from data, are considered to beuncorrelated. The 95% C.L. lower limits on MD fromeach candidate sample and the combined limits are givenin Table III and plotted with LEP limits [15] in Fig. 3.

In conclusion, the CDF experiment has recently com-pleted searches for new physics in the ! + E/T and jet +E/T final states using data corresponding to 2.0 fb!1 and

q

q

!

G

Page 115: Slac Summer Institute 2009

Large Extra Dimension SignaturesBlack Holes at the LHC

Topology Total Cross Section (fb)

n = 2 62, 000

5 TeV black hole n = 4 37, 000

n = 6 34, 000

n = 2 580

8 TeV black hole n = 4 310

n = 6 270

n = 2 6.7

10 TeV black hole n = 4 3.4

n = 6 2.9

Table 1: The black hole production cross sections at the LHC for MPL = 1 TeV as given byCHARYBDIS. Note that CHARYBDIS does not include the form factors mentioned in section 7.

in order for our analyses to be as widely applicable as possible. In this section we review

these uncertainties.

4.1 Production cross section

The process of black hole production in hadron collisions is subject to a number of basic

uncertainties. The order of magnitude of the parton-level cross section should be given by

equation 2.1, but the form factor relating the left- and right-hand sides is uncertain and

would be expected to be n-dependent. Classical numerical simulations [26] suggest values

in the range 0.5–2, increasing with n. These values are not included in the CHARYBDIS

generator, but we take them into account when cross section data are used in our analysis

(in sections 7 and 8).

More fundamentally, the transition from the parton-level to the hadron-level cross

section is based on the factorization formula

!(S) =

!

dx1 dx2 f(x1)f(x2)!(s = x1x2S) (4.1)

where f(x) is the parton distribution function (PDF) summed over parton flavours. The

validity of this formula in the trans-Planckian energy region is unclear. Even if factoriza-

tion remains valid, the extrapolation of the PDFs into this region based on Standard Model

evolution from present energies is questionable. Also, comparison to Standard Model pro-

cesses in the trans-Planckian regime would be di!cult since perturbative physics would be

suppressed.

4.2 The first stages of decay

CHARYBDIS does not model the initial balding or spin-down phases of the black hole decay.

The amount of energy emitted from the black hole during these phases is expected to be

small [8] so such an omission should not be significant. However, it is probable that the

energy spectrum will be modified at low energies.

– 5 –

Rs(!

s) = M!1"

!!s

M"

" 1n+1!

s"M!for !BH ! R2s

BHs decaythermally, violating all

global conservation laws

High multiplicity eventswith lots of energy

qq

Page 116: Slac Summer Institute 2009

Universal Extra Dimensions

+GravitySM

Standard Model has KK modes

S5D =!

d5x F 2MN + !iD! ! + · · ·

!12R " x5 "

12R

All fields go in the bulk

R!1 >! 500 GeV

Page 117: Slac Summer Institute 2009

Universal Extra Dimensions

+GravitySM

Standard Model has KK modes

S5D =!

d5x F 2MN + !iD! ! + · · ·

!12R " x5 "

12R

All fields go in the bulkM

ass

g W B Q U c Dc L Ec H

n = 1

n = 2n = 3· · ·

n = 0

f(x5)

1

sin(x5/R)

cos(2x5/R)sin(3x5/R)

Impose Dirichlet Boundary Conditions

R!1 >! 500 GeV

Page 118: Slac Summer Institute 2009

UED KK Spectra

FIG. 6: The spectrum of the first KK level at (a) tree level and (b) one-loop, for R!1 = 500 GeV,

!R = 20, mh = 120 GeV, m2H = 0, and assuming vanishing boundary terms at the cut-o" scale !.

R!1 = 500 GeV, !R = 20, mh = 120 GeV, m2H = 0 and assumed vanishing boundary

terms at the cut-o" scale !. We see that the KK “photon” receives the smallest corrections

and is the lightest state at each KK level. Unbroken KK parity (!1)KK implies that the

lightest KK particle (LKP) at level one is stable. Hence the “photon” LKP !1 provides an

interesting dark matter candidate. The corrections to the masses of the other first level KK

states are generally large enough that they will have prompt cascade decays down to !1.3

Therefore KK production at colliders results in generic missing energy signatures, similar

to supersymmetric models with stable neutralino LSP. Collider searches for this scenario

appear to be rather challenging because of the KK mass degeneracy and will be discussed

in a separate publication [13].

V. CONCLUSIONS

Loop corrections to the masses of Kaluza-Klein excitations can play an important role

in the phenomenology of extra dimensional theories. This is because KK states of a given

level are all nearly degenerate, so that small corrections can determine which states decay

and which are stable.

3 The first level graviton G1 (or right-handed neutrino N1 if the theory includes right handed neutrinos N0)

could also be the LKP. However, the decay lifetime of !1 to G1 or N1 would be comparable to cosmo-

logical scales. Therefore, G1 and N1 are irrelevant for collider phenomenology but may have interesting

consequences for cosmology.

20

Levels are degenerate at tree level

All masses within 30% of each other!(This is a widely spaced example!)

Page 119: Slac Summer Institute 2009

KK Parityx5 ! "x5

All odd-leveled KK modes are oddSM and even-leveled KK modes are even

Page 120: Slac Summer Institute 2009

KK Parityx5 ! "x5

All odd-leveled KK modes are oddSM and even-leveled KK modes are even

LKP is stable!

Usually KK partner of Hypercharge Gauge boson

g0,0,1 !! R/2

!R/2dx5 f0(x5)f0(x5)f1(x5) "

!dx5 1 · 1 · sin(!x5/R)

Page 121: Slac Summer Institute 2009

KK Parityx5 ! "x5

All odd-leveled KK modes are oddSM and even-leveled KK modes are even

Looks like a degenerate Supersymmetry spectrumuntil you can see 2nd KK level

LKP is stable!

Usually KK partner of Hypercharge Gauge boson

g0,0,1 !! R/2

!R/2dx5 f0(x5)f0(x5)f1(x5) "

!dx5 1 · 1 · sin(!x5/R)

Page 122: Slac Summer Institute 2009

Typical UED EventPair produce colored 1st KK level

Each side decays separately

FIG. 6: The spectrum of the first KK level at (a) tree level and (b) one-loop, for R!1 = 500 GeV,

!R = 20, mh = 120 GeV, m2H = 0, and assuming vanishing boundary terms at the cut-o" scale !.

R!1 = 500 GeV, !R = 20, mh = 120 GeV, m2H = 0 and assumed vanishing boundary

terms at the cut-o" scale !. We see that the KK “photon” receives the smallest corrections

and is the lightest state at each KK level. Unbroken KK parity (!1)KK implies that the

lightest KK particle (LKP) at level one is stable. Hence the “photon” LKP !1 provides an

interesting dark matter candidate. The corrections to the masses of the other first level KK

states are generally large enough that they will have prompt cascade decays down to !1.3

Therefore KK production at colliders results in generic missing energy signatures, similar

to supersymmetric models with stable neutralino LSP. Collider searches for this scenario

appear to be rather challenging because of the KK mass degeneracy and will be discussed

in a separate publication [13].

V. CONCLUSIONS

Loop corrections to the masses of Kaluza-Klein excitations can play an important role

in the phenomenology of extra dimensional theories. This is because KK states of a given

level are all nearly degenerate, so that small corrections can determine which states decay

and which are stable.

3 The first level graviton G1 (or right-handed neutrino N1 if the theory includes right handed neutrinos N0)

could also be the LKP. However, the decay lifetime of !1 to G1 or N1 would be comparable to cosmo-

logical scales. Therefore, G1 and N1 are irrelevant for collider phenomenology but may have interesting

consequences for cosmology.

20

FIG. 6: The spectrum of the first KK level at (a) tree level and (b) one-loop, for R!1 = 500 GeV,

!R = 20, mh = 120 GeV, m2H = 0, and assuming vanishing boundary terms at the cut-o" scale !.

R!1 = 500 GeV, !R = 20, mh = 120 GeV, m2H = 0 and assumed vanishing boundary

terms at the cut-o" scale !. We see that the KK “photon” receives the smallest corrections

and is the lightest state at each KK level. Unbroken KK parity (!1)KK implies that the

lightest KK particle (LKP) at level one is stable. Hence the “photon” LKP !1 provides an

interesting dark matter candidate. The corrections to the masses of the other first level KK

states are generally large enough that they will have prompt cascade decays down to !1.3

Therefore KK production at colliders results in generic missing energy signatures, similar

to supersymmetric models with stable neutralino LSP. Collider searches for this scenario

appear to be rather challenging because of the KK mass degeneracy and will be discussed

in a separate publication [13].

V. CONCLUSIONS

Loop corrections to the masses of Kaluza-Klein excitations can play an important role

in the phenomenology of extra dimensional theories. This is because KK states of a given

level are all nearly degenerate, so that small corrections can determine which states decay

and which are stable.

3 The first level graviton G1 (or right-handed neutrino N1 if the theory includes right handed neutrinos N0)

could also be the LKP. However, the decay lifetime of !1 to G1 or N1 would be comparable to cosmo-

logical scales. Therefore, G1 and N1 are irrelevant for collider phenomenology but may have interesting

consequences for cosmology.

20

Page 123: Slac Summer Institute 2009

Typical UED EventPair produce colored 1st KK level

Each side decays separately

FIG. 6: The spectrum of the first KK level at (a) tree level and (b) one-loop, for R!1 = 500 GeV,

!R = 20, mh = 120 GeV, m2H = 0, and assuming vanishing boundary terms at the cut-o" scale !.

R!1 = 500 GeV, !R = 20, mh = 120 GeV, m2H = 0 and assumed vanishing boundary

terms at the cut-o" scale !. We see that the KK “photon” receives the smallest corrections

and is the lightest state at each KK level. Unbroken KK parity (!1)KK implies that the

lightest KK particle (LKP) at level one is stable. Hence the “photon” LKP !1 provides an

interesting dark matter candidate. The corrections to the masses of the other first level KK

states are generally large enough that they will have prompt cascade decays down to !1.3

Therefore KK production at colliders results in generic missing energy signatures, similar

to supersymmetric models with stable neutralino LSP. Collider searches for this scenario

appear to be rather challenging because of the KK mass degeneracy and will be discussed

in a separate publication [13].

V. CONCLUSIONS

Loop corrections to the masses of Kaluza-Klein excitations can play an important role

in the phenomenology of extra dimensional theories. This is because KK states of a given

level are all nearly degenerate, so that small corrections can determine which states decay

and which are stable.

3 The first level graviton G1 (or right-handed neutrino N1 if the theory includes right handed neutrinos N0)

could also be the LKP. However, the decay lifetime of !1 to G1 or N1 would be comparable to cosmo-

logical scales. Therefore, G1 and N1 are irrelevant for collider phenomenology but may have interesting

consequences for cosmology.

20

FIG. 6: The spectrum of the first KK level at (a) tree level and (b) one-loop, for R!1 = 500 GeV,

!R = 20, mh = 120 GeV, m2H = 0, and assuming vanishing boundary terms at the cut-o" scale !.

R!1 = 500 GeV, !R = 20, mh = 120 GeV, m2H = 0 and assumed vanishing boundary

terms at the cut-o" scale !. We see that the KK “photon” receives the smallest corrections

and is the lightest state at each KK level. Unbroken KK parity (!1)KK implies that the

lightest KK particle (LKP) at level one is stable. Hence the “photon” LKP !1 provides an

interesting dark matter candidate. The corrections to the masses of the other first level KK

states are generally large enough that they will have prompt cascade decays down to !1.3

Therefore KK production at colliders results in generic missing energy signatures, similar

to supersymmetric models with stable neutralino LSP. Collider searches for this scenario

appear to be rather challenging because of the KK mass degeneracy and will be discussed

in a separate publication [13].

V. CONCLUSIONS

Loop corrections to the masses of Kaluza-Klein excitations can play an important role

in the phenomenology of extra dimensional theories. This is because KK states of a given

level are all nearly degenerate, so that small corrections can determine which states decay

and which are stable.

3 The first level graviton G1 (or right-handed neutrino N1 if the theory includes right handed neutrinos N0)

could also be the LKP. However, the decay lifetime of !1 to G1 or N1 would be comparable to cosmo-

logical scales. Therefore, G1 and N1 are irrelevant for collider phenomenology but may have interesting

consequences for cosmology.

20

g1 ! q1q

Page 124: Slac Summer Institute 2009

Typical UED EventPair produce colored 1st KK level

Each side decays separately

FIG. 6: The spectrum of the first KK level at (a) tree level and (b) one-loop, for R!1 = 500 GeV,

!R = 20, mh = 120 GeV, m2H = 0, and assuming vanishing boundary terms at the cut-o" scale !.

R!1 = 500 GeV, !R = 20, mh = 120 GeV, m2H = 0 and assumed vanishing boundary

terms at the cut-o" scale !. We see that the KK “photon” receives the smallest corrections

and is the lightest state at each KK level. Unbroken KK parity (!1)KK implies that the

lightest KK particle (LKP) at level one is stable. Hence the “photon” LKP !1 provides an

interesting dark matter candidate. The corrections to the masses of the other first level KK

states are generally large enough that they will have prompt cascade decays down to !1.3

Therefore KK production at colliders results in generic missing energy signatures, similar

to supersymmetric models with stable neutralino LSP. Collider searches for this scenario

appear to be rather challenging because of the KK mass degeneracy and will be discussed

in a separate publication [13].

V. CONCLUSIONS

Loop corrections to the masses of Kaluza-Klein excitations can play an important role

in the phenomenology of extra dimensional theories. This is because KK states of a given

level are all nearly degenerate, so that small corrections can determine which states decay

and which are stable.

3 The first level graviton G1 (or right-handed neutrino N1 if the theory includes right handed neutrinos N0)

could also be the LKP. However, the decay lifetime of !1 to G1 or N1 would be comparable to cosmo-

logical scales. Therefore, G1 and N1 are irrelevant for collider phenomenology but may have interesting

consequences for cosmology.

20

FIG. 6: The spectrum of the first KK level at (a) tree level and (b) one-loop, for R!1 = 500 GeV,

!R = 20, mh = 120 GeV, m2H = 0, and assuming vanishing boundary terms at the cut-o" scale !.

R!1 = 500 GeV, !R = 20, mh = 120 GeV, m2H = 0 and assumed vanishing boundary

terms at the cut-o" scale !. We see that the KK “photon” receives the smallest corrections

and is the lightest state at each KK level. Unbroken KK parity (!1)KK implies that the

lightest KK particle (LKP) at level one is stable. Hence the “photon” LKP !1 provides an

interesting dark matter candidate. The corrections to the masses of the other first level KK

states are generally large enough that they will have prompt cascade decays down to !1.3

Therefore KK production at colliders results in generic missing energy signatures, similar

to supersymmetric models with stable neutralino LSP. Collider searches for this scenario

appear to be rather challenging because of the KK mass degeneracy and will be discussed

in a separate publication [13].

V. CONCLUSIONS

Loop corrections to the masses of Kaluza-Klein excitations can play an important role

in the phenomenology of extra dimensional theories. This is because KK states of a given

level are all nearly degenerate, so that small corrections can determine which states decay

and which are stable.

3 The first level graviton G1 (or right-handed neutrino N1 if the theory includes right handed neutrinos N0)

could also be the LKP. However, the decay lifetime of !1 to G1 or N1 would be comparable to cosmo-

logical scales. Therefore, G1 and N1 are irrelevant for collider phenomenology but may have interesting

consequences for cosmology.

20

q1 ! B1q

g1 ! q1q

Page 125: Slac Summer Institute 2009

Typical UED EventPair produce colored 1st KK level

Each side decays separately

FIG. 6: The spectrum of the first KK level at (a) tree level and (b) one-loop, for R!1 = 500 GeV,

!R = 20, mh = 120 GeV, m2H = 0, and assuming vanishing boundary terms at the cut-o" scale !.

R!1 = 500 GeV, !R = 20, mh = 120 GeV, m2H = 0 and assumed vanishing boundary

terms at the cut-o" scale !. We see that the KK “photon” receives the smallest corrections

and is the lightest state at each KK level. Unbroken KK parity (!1)KK implies that the

lightest KK particle (LKP) at level one is stable. Hence the “photon” LKP !1 provides an

interesting dark matter candidate. The corrections to the masses of the other first level KK

states are generally large enough that they will have prompt cascade decays down to !1.3

Therefore KK production at colliders results in generic missing energy signatures, similar

to supersymmetric models with stable neutralino LSP. Collider searches for this scenario

appear to be rather challenging because of the KK mass degeneracy and will be discussed

in a separate publication [13].

V. CONCLUSIONS

Loop corrections to the masses of Kaluza-Klein excitations can play an important role

in the phenomenology of extra dimensional theories. This is because KK states of a given

level are all nearly degenerate, so that small corrections can determine which states decay

and which are stable.

3 The first level graviton G1 (or right-handed neutrino N1 if the theory includes right handed neutrinos N0)

could also be the LKP. However, the decay lifetime of !1 to G1 or N1 would be comparable to cosmo-

logical scales. Therefore, G1 and N1 are irrelevant for collider phenomenology but may have interesting

consequences for cosmology.

20

FIG. 6: The spectrum of the first KK level at (a) tree level and (b) one-loop, for R!1 = 500 GeV,

!R = 20, mh = 120 GeV, m2H = 0, and assuming vanishing boundary terms at the cut-o" scale !.

R!1 = 500 GeV, !R = 20, mh = 120 GeV, m2H = 0 and assumed vanishing boundary

terms at the cut-o" scale !. We see that the KK “photon” receives the smallest corrections

and is the lightest state at each KK level. Unbroken KK parity (!1)KK implies that the

lightest KK particle (LKP) at level one is stable. Hence the “photon” LKP !1 provides an

interesting dark matter candidate. The corrections to the masses of the other first level KK

states are generally large enough that they will have prompt cascade decays down to !1.3

Therefore KK production at colliders results in generic missing energy signatures, similar

to supersymmetric models with stable neutralino LSP. Collider searches for this scenario

appear to be rather challenging because of the KK mass degeneracy and will be discussed

in a separate publication [13].

V. CONCLUSIONS

Loop corrections to the masses of Kaluza-Klein excitations can play an important role

in the phenomenology of extra dimensional theories. This is because KK states of a given

level are all nearly degenerate, so that small corrections can determine which states decay

and which are stable.

3 The first level graviton G1 (or right-handed neutrino N1 if the theory includes right handed neutrinos N0)

could also be the LKP. However, the decay lifetime of !1 to G1 or N1 would be comparable to cosmo-

logical scales. Therefore, G1 and N1 are irrelevant for collider phenomenology but may have interesting

consequences for cosmology.

20

q1 ! B1q

g1 ! q1q

2j + ET!

Page 126: Slac Summer Institute 2009

Typical UED EventPair produce colored 1st KK level

Each side decays separately

FIG. 6: The spectrum of the first KK level at (a) tree level and (b) one-loop, for R!1 = 500 GeV,

!R = 20, mh = 120 GeV, m2H = 0, and assuming vanishing boundary terms at the cut-o" scale !.

R!1 = 500 GeV, !R = 20, mh = 120 GeV, m2H = 0 and assumed vanishing boundary

terms at the cut-o" scale !. We see that the KK “photon” receives the smallest corrections

and is the lightest state at each KK level. Unbroken KK parity (!1)KK implies that the

lightest KK particle (LKP) at level one is stable. Hence the “photon” LKP !1 provides an

interesting dark matter candidate. The corrections to the masses of the other first level KK

states are generally large enough that they will have prompt cascade decays down to !1.3

Therefore KK production at colliders results in generic missing energy signatures, similar

to supersymmetric models with stable neutralino LSP. Collider searches for this scenario

appear to be rather challenging because of the KK mass degeneracy and will be discussed

in a separate publication [13].

V. CONCLUSIONS

Loop corrections to the masses of Kaluza-Klein excitations can play an important role

in the phenomenology of extra dimensional theories. This is because KK states of a given

level are all nearly degenerate, so that small corrections can determine which states decay

and which are stable.

3 The first level graviton G1 (or right-handed neutrino N1 if the theory includes right handed neutrinos N0)

could also be the LKP. However, the decay lifetime of !1 to G1 or N1 would be comparable to cosmo-

logical scales. Therefore, G1 and N1 are irrelevant for collider phenomenology but may have interesting

consequences for cosmology.

20

FIG. 6: The spectrum of the first KK level at (a) tree level and (b) one-loop, for R!1 = 500 GeV,

!R = 20, mh = 120 GeV, m2H = 0, and assuming vanishing boundary terms at the cut-o" scale !.

R!1 = 500 GeV, !R = 20, mh = 120 GeV, m2H = 0 and assumed vanishing boundary

terms at the cut-o" scale !. We see that the KK “photon” receives the smallest corrections

and is the lightest state at each KK level. Unbroken KK parity (!1)KK implies that the

lightest KK particle (LKP) at level one is stable. Hence the “photon” LKP !1 provides an

interesting dark matter candidate. The corrections to the masses of the other first level KK

states are generally large enough that they will have prompt cascade decays down to !1.3

Therefore KK production at colliders results in generic missing energy signatures, similar

to supersymmetric models with stable neutralino LSP. Collider searches for this scenario

appear to be rather challenging because of the KK mass degeneracy and will be discussed

in a separate publication [13].

V. CONCLUSIONS

Loop corrections to the masses of Kaluza-Klein excitations can play an important role

in the phenomenology of extra dimensional theories. This is because KK states of a given

level are all nearly degenerate, so that small corrections can determine which states decay

and which are stable.

3 The first level graviton G1 (or right-handed neutrino N1 if the theory includes right handed neutrinos N0)

could also be the LKP. However, the decay lifetime of !1 to G1 or N1 would be comparable to cosmo-

logical scales. Therefore, G1 and N1 are irrelevant for collider phenomenology but may have interesting

consequences for cosmology.

20

g1 ! q1q

q1 ! B1q

g1 ! q1q

2j + ET!

Page 127: Slac Summer Institute 2009

Typical UED EventPair produce colored 1st KK level

Each side decays separately

FIG. 6: The spectrum of the first KK level at (a) tree level and (b) one-loop, for R!1 = 500 GeV,

!R = 20, mh = 120 GeV, m2H = 0, and assuming vanishing boundary terms at the cut-o" scale !.

R!1 = 500 GeV, !R = 20, mh = 120 GeV, m2H = 0 and assumed vanishing boundary

terms at the cut-o" scale !. We see that the KK “photon” receives the smallest corrections

and is the lightest state at each KK level. Unbroken KK parity (!1)KK implies that the

lightest KK particle (LKP) at level one is stable. Hence the “photon” LKP !1 provides an

interesting dark matter candidate. The corrections to the masses of the other first level KK

states are generally large enough that they will have prompt cascade decays down to !1.3

Therefore KK production at colliders results in generic missing energy signatures, similar

to supersymmetric models with stable neutralino LSP. Collider searches for this scenario

appear to be rather challenging because of the KK mass degeneracy and will be discussed

in a separate publication [13].

V. CONCLUSIONS

Loop corrections to the masses of Kaluza-Klein excitations can play an important role

in the phenomenology of extra dimensional theories. This is because KK states of a given

level are all nearly degenerate, so that small corrections can determine which states decay

and which are stable.

3 The first level graviton G1 (or right-handed neutrino N1 if the theory includes right handed neutrinos N0)

could also be the LKP. However, the decay lifetime of !1 to G1 or N1 would be comparable to cosmo-

logical scales. Therefore, G1 and N1 are irrelevant for collider phenomenology but may have interesting

consequences for cosmology.

20

FIG. 6: The spectrum of the first KK level at (a) tree level and (b) one-loop, for R!1 = 500 GeV,

!R = 20, mh = 120 GeV, m2H = 0, and assuming vanishing boundary terms at the cut-o" scale !.

R!1 = 500 GeV, !R = 20, mh = 120 GeV, m2H = 0 and assumed vanishing boundary

terms at the cut-o" scale !. We see that the KK “photon” receives the smallest corrections

and is the lightest state at each KK level. Unbroken KK parity (!1)KK implies that the

lightest KK particle (LKP) at level one is stable. Hence the “photon” LKP !1 provides an

interesting dark matter candidate. The corrections to the masses of the other first level KK

states are generally large enough that they will have prompt cascade decays down to !1.3

Therefore KK production at colliders results in generic missing energy signatures, similar

to supersymmetric models with stable neutralino LSP. Collider searches for this scenario

appear to be rather challenging because of the KK mass degeneracy and will be discussed

in a separate publication [13].

V. CONCLUSIONS

Loop corrections to the masses of Kaluza-Klein excitations can play an important role

in the phenomenology of extra dimensional theories. This is because KK states of a given

level are all nearly degenerate, so that small corrections can determine which states decay

and which are stable.

3 The first level graviton G1 (or right-handed neutrino N1 if the theory includes right handed neutrinos N0)

could also be the LKP. However, the decay lifetime of !1 to G1 or N1 would be comparable to cosmo-

logical scales. Therefore, G1 and N1 are irrelevant for collider phenomenology but may have interesting

consequences for cosmology.

20

g1 ! q1q

q1 ! B1q

g1 ! q1q

q1 !W 31 q

2j + ET!

Page 128: Slac Summer Institute 2009

Typical UED EventPair produce colored 1st KK level

Each side decays separately

FIG. 6: The spectrum of the first KK level at (a) tree level and (b) one-loop, for R!1 = 500 GeV,

!R = 20, mh = 120 GeV, m2H = 0, and assuming vanishing boundary terms at the cut-o" scale !.

R!1 = 500 GeV, !R = 20, mh = 120 GeV, m2H = 0 and assumed vanishing boundary

terms at the cut-o" scale !. We see that the KK “photon” receives the smallest corrections

and is the lightest state at each KK level. Unbroken KK parity (!1)KK implies that the

lightest KK particle (LKP) at level one is stable. Hence the “photon” LKP !1 provides an

interesting dark matter candidate. The corrections to the masses of the other first level KK

states are generally large enough that they will have prompt cascade decays down to !1.3

Therefore KK production at colliders results in generic missing energy signatures, similar

to supersymmetric models with stable neutralino LSP. Collider searches for this scenario

appear to be rather challenging because of the KK mass degeneracy and will be discussed

in a separate publication [13].

V. CONCLUSIONS

Loop corrections to the masses of Kaluza-Klein excitations can play an important role

in the phenomenology of extra dimensional theories. This is because KK states of a given

level are all nearly degenerate, so that small corrections can determine which states decay

and which are stable.

3 The first level graviton G1 (or right-handed neutrino N1 if the theory includes right handed neutrinos N0)

could also be the LKP. However, the decay lifetime of !1 to G1 or N1 would be comparable to cosmo-

logical scales. Therefore, G1 and N1 are irrelevant for collider phenomenology but may have interesting

consequences for cosmology.

20

FIG. 6: The spectrum of the first KK level at (a) tree level and (b) one-loop, for R!1 = 500 GeV,

!R = 20, mh = 120 GeV, m2H = 0, and assuming vanishing boundary terms at the cut-o" scale !.

R!1 = 500 GeV, !R = 20, mh = 120 GeV, m2H = 0 and assumed vanishing boundary

terms at the cut-o" scale !. We see that the KK “photon” receives the smallest corrections

and is the lightest state at each KK level. Unbroken KK parity (!1)KK implies that the

lightest KK particle (LKP) at level one is stable. Hence the “photon” LKP !1 provides an

interesting dark matter candidate. The corrections to the masses of the other first level KK

states are generally large enough that they will have prompt cascade decays down to !1.3

Therefore KK production at colliders results in generic missing energy signatures, similar

to supersymmetric models with stable neutralino LSP. Collider searches for this scenario

appear to be rather challenging because of the KK mass degeneracy and will be discussed

in a separate publication [13].

V. CONCLUSIONS

Loop corrections to the masses of Kaluza-Klein excitations can play an important role

in the phenomenology of extra dimensional theories. This is because KK states of a given

level are all nearly degenerate, so that small corrections can determine which states decay

and which are stable.

3 The first level graviton G1 (or right-handed neutrino N1 if the theory includes right handed neutrinos N0)

could also be the LKP. However, the decay lifetime of !1 to G1 or N1 would be comparable to cosmo-

logical scales. Therefore, G1 and N1 are irrelevant for collider phenomenology but may have interesting

consequences for cosmology.

20

g1 ! q1q

q1 ! B1q

g1 ! q1q

q1 !W 31 q

W 31 ! !1!

2j + ET!

Page 129: Slac Summer Institute 2009

Typical UED EventPair produce colored 1st KK level

Each side decays separately

FIG. 6: The spectrum of the first KK level at (a) tree level and (b) one-loop, for R!1 = 500 GeV,

!R = 20, mh = 120 GeV, m2H = 0, and assuming vanishing boundary terms at the cut-o" scale !.

R!1 = 500 GeV, !R = 20, mh = 120 GeV, m2H = 0 and assumed vanishing boundary

terms at the cut-o" scale !. We see that the KK “photon” receives the smallest corrections

and is the lightest state at each KK level. Unbroken KK parity (!1)KK implies that the

lightest KK particle (LKP) at level one is stable. Hence the “photon” LKP !1 provides an

interesting dark matter candidate. The corrections to the masses of the other first level KK

states are generally large enough that they will have prompt cascade decays down to !1.3

Therefore KK production at colliders results in generic missing energy signatures, similar

to supersymmetric models with stable neutralino LSP. Collider searches for this scenario

appear to be rather challenging because of the KK mass degeneracy and will be discussed

in a separate publication [13].

V. CONCLUSIONS

Loop corrections to the masses of Kaluza-Klein excitations can play an important role

in the phenomenology of extra dimensional theories. This is because KK states of a given

level are all nearly degenerate, so that small corrections can determine which states decay

and which are stable.

3 The first level graviton G1 (or right-handed neutrino N1 if the theory includes right handed neutrinos N0)

could also be the LKP. However, the decay lifetime of !1 to G1 or N1 would be comparable to cosmo-

logical scales. Therefore, G1 and N1 are irrelevant for collider phenomenology but may have interesting

consequences for cosmology.

20

FIG. 6: The spectrum of the first KK level at (a) tree level and (b) one-loop, for R!1 = 500 GeV,

!R = 20, mh = 120 GeV, m2H = 0, and assuming vanishing boundary terms at the cut-o" scale !.

R!1 = 500 GeV, !R = 20, mh = 120 GeV, m2H = 0 and assumed vanishing boundary

terms at the cut-o" scale !. We see that the KK “photon” receives the smallest corrections

and is the lightest state at each KK level. Unbroken KK parity (!1)KK implies that the

lightest KK particle (LKP) at level one is stable. Hence the “photon” LKP !1 provides an

interesting dark matter candidate. The corrections to the masses of the other first level KK

states are generally large enough that they will have prompt cascade decays down to !1.3

Therefore KK production at colliders results in generic missing energy signatures, similar

to supersymmetric models with stable neutralino LSP. Collider searches for this scenario

appear to be rather challenging because of the KK mass degeneracy and will be discussed

in a separate publication [13].

V. CONCLUSIONS

Loop corrections to the masses of Kaluza-Klein excitations can play an important role

in the phenomenology of extra dimensional theories. This is because KK states of a given

level are all nearly degenerate, so that small corrections can determine which states decay

and which are stable.

3 The first level graviton G1 (or right-handed neutrino N1 if the theory includes right handed neutrinos N0)

could also be the LKP. However, the decay lifetime of !1 to G1 or N1 would be comparable to cosmo-

logical scales. Therefore, G1 and N1 are irrelevant for collider phenomenology but may have interesting

consequences for cosmology.

20

g1 ! q1q

q1 ! B1q

g1 ! q1q

q1 !W 31 q

W 31 ! !1!

!1 ! !B1

2j + ET!

Page 130: Slac Summer Institute 2009

Typical UED EventPair produce colored 1st KK level

Each side decays separately

FIG. 6: The spectrum of the first KK level at (a) tree level and (b) one-loop, for R!1 = 500 GeV,

!R = 20, mh = 120 GeV, m2H = 0, and assuming vanishing boundary terms at the cut-o" scale !.

R!1 = 500 GeV, !R = 20, mh = 120 GeV, m2H = 0 and assumed vanishing boundary

terms at the cut-o" scale !. We see that the KK “photon” receives the smallest corrections

and is the lightest state at each KK level. Unbroken KK parity (!1)KK implies that the

lightest KK particle (LKP) at level one is stable. Hence the “photon” LKP !1 provides an

interesting dark matter candidate. The corrections to the masses of the other first level KK

states are generally large enough that they will have prompt cascade decays down to !1.3

Therefore KK production at colliders results in generic missing energy signatures, similar

to supersymmetric models with stable neutralino LSP. Collider searches for this scenario

appear to be rather challenging because of the KK mass degeneracy and will be discussed

in a separate publication [13].

V. CONCLUSIONS

Loop corrections to the masses of Kaluza-Klein excitations can play an important role

in the phenomenology of extra dimensional theories. This is because KK states of a given

level are all nearly degenerate, so that small corrections can determine which states decay

and which are stable.

3 The first level graviton G1 (or right-handed neutrino N1 if the theory includes right handed neutrinos N0)

could also be the LKP. However, the decay lifetime of !1 to G1 or N1 would be comparable to cosmo-

logical scales. Therefore, G1 and N1 are irrelevant for collider phenomenology but may have interesting

consequences for cosmology.

20

FIG. 6: The spectrum of the first KK level at (a) tree level and (b) one-loop, for R!1 = 500 GeV,

!R = 20, mh = 120 GeV, m2H = 0, and assuming vanishing boundary terms at the cut-o" scale !.

R!1 = 500 GeV, !R = 20, mh = 120 GeV, m2H = 0 and assumed vanishing boundary

terms at the cut-o" scale !. We see that the KK “photon” receives the smallest corrections

and is the lightest state at each KK level. Unbroken KK parity (!1)KK implies that the

lightest KK particle (LKP) at level one is stable. Hence the “photon” LKP !1 provides an

interesting dark matter candidate. The corrections to the masses of the other first level KK

states are generally large enough that they will have prompt cascade decays down to !1.3

Therefore KK production at colliders results in generic missing energy signatures, similar

to supersymmetric models with stable neutralino LSP. Collider searches for this scenario

appear to be rather challenging because of the KK mass degeneracy and will be discussed

in a separate publication [13].

V. CONCLUSIONS

Loop corrections to the masses of Kaluza-Klein excitations can play an important role

in the phenomenology of extra dimensional theories. This is because KK states of a given

level are all nearly degenerate, so that small corrections can determine which states decay

and which are stable.

3 The first level graviton G1 (or right-handed neutrino N1 if the theory includes right handed neutrinos N0)

could also be the LKP. However, the decay lifetime of !1 to G1 or N1 would be comparable to cosmo-

logical scales. Therefore, G1 and N1 are irrelevant for collider phenomenology but may have interesting

consequences for cosmology.

20

g1 ! q1q

q1 ! B1q

g1 ! q1q

q1 !W 31 q

W 31 ! !1!

!1 ! !B1

2j + ET! 2j + ! + ! + ET!

Page 131: Slac Summer Institute 2009

Typical UED EventPair produce colored 1st KK level

Each side decays separately

FIG. 6: The spectrum of the first KK level at (a) tree level and (b) one-loop, for R!1 = 500 GeV,

!R = 20, mh = 120 GeV, m2H = 0, and assuming vanishing boundary terms at the cut-o" scale !.

R!1 = 500 GeV, !R = 20, mh = 120 GeV, m2H = 0 and assumed vanishing boundary

terms at the cut-o" scale !. We see that the KK “photon” receives the smallest corrections

and is the lightest state at each KK level. Unbroken KK parity (!1)KK implies that the

lightest KK particle (LKP) at level one is stable. Hence the “photon” LKP !1 provides an

interesting dark matter candidate. The corrections to the masses of the other first level KK

states are generally large enough that they will have prompt cascade decays down to !1.3

Therefore KK production at colliders results in generic missing energy signatures, similar

to supersymmetric models with stable neutralino LSP. Collider searches for this scenario

appear to be rather challenging because of the KK mass degeneracy and will be discussed

in a separate publication [13].

V. CONCLUSIONS

Loop corrections to the masses of Kaluza-Klein excitations can play an important role

in the phenomenology of extra dimensional theories. This is because KK states of a given

level are all nearly degenerate, so that small corrections can determine which states decay

and which are stable.

3 The first level graviton G1 (or right-handed neutrino N1 if the theory includes right handed neutrinos N0)

could also be the LKP. However, the decay lifetime of !1 to G1 or N1 would be comparable to cosmo-

logical scales. Therefore, G1 and N1 are irrelevant for collider phenomenology but may have interesting

consequences for cosmology.

20

FIG. 6: The spectrum of the first KK level at (a) tree level and (b) one-loop, for R!1 = 500 GeV,

!R = 20, mh = 120 GeV, m2H = 0, and assuming vanishing boundary terms at the cut-o" scale !.

R!1 = 500 GeV, !R = 20, mh = 120 GeV, m2H = 0 and assumed vanishing boundary

terms at the cut-o" scale !. We see that the KK “photon” receives the smallest corrections

and is the lightest state at each KK level. Unbroken KK parity (!1)KK implies that the

lightest KK particle (LKP) at level one is stable. Hence the “photon” LKP !1 provides an

interesting dark matter candidate. The corrections to the masses of the other first level KK

states are generally large enough that they will have prompt cascade decays down to !1.3

Therefore KK production at colliders results in generic missing energy signatures, similar

to supersymmetric models with stable neutralino LSP. Collider searches for this scenario

appear to be rather challenging because of the KK mass degeneracy and will be discussed

in a separate publication [13].

V. CONCLUSIONS

Loop corrections to the masses of Kaluza-Klein excitations can play an important role

in the phenomenology of extra dimensional theories. This is because KK states of a given

level are all nearly degenerate, so that small corrections can determine which states decay

and which are stable.

3 The first level graviton G1 (or right-handed neutrino N1 if the theory includes right handed neutrinos N0)

could also be the LKP. However, the decay lifetime of !1 to G1 or N1 would be comparable to cosmo-

logical scales. Therefore, G1 and N1 are irrelevant for collider phenomenology but may have interesting

consequences for cosmology.

20

g1 ! q1q

q1 ! B1q

g1 ! q1q

q1 !W 31 q

W 31 ! !1!

!1 ! !B1

2j + ET! 2j + ! + ! + ET!

Difficult is in Soft Spectra

Page 132: Slac Summer Institute 2009

Randall Sundrum ModelsTeV Scale Curved Extra Dimensions

ds2 = e!2kydx24 ! dy2

Warp factor

UV Brane IR Brane

y

0 ! y ! y0

At each point of the 5th dimension,there is a different normalization of 4D lengths

Page 133: Slac Summer Institute 2009

Effects of the Warping

S5 =!

d4xdy!

g5 !(y " y0)"gµ!5 "µ#"!# + m2#2 + g#3 + $#4

#

gµ!5 = e2ky0!µ!!

g5 = e!4ky0

An IR brane scalar

Page 134: Slac Summer Institute 2009

Effects of the Warping

S5 =!

d4xdy!

g5 !(y " y0)"gµ!5 "µ#"!# + m2#2 + g#3 + $#4

#

gµ!5 = e2ky0!µ!!

g5 = e!4ky0

S4 =!

d4x e!4ky0"e2ky0(!")2 + m2"2 + g"3 + #"4

#

Need to go to canonical normalization !! eky0!

An IR brane scalar

Page 135: Slac Summer Institute 2009

Effects of the Warping

S5 =!

d4xdy!

g5 !(y " y0)"gµ!5 "µ#"!# + m2#2 + g#3 + $#4

#

gµ!5 = e2ky0!µ!!

g5 = e!4ky0

S4 =!

d4x e!4ky0"e2ky0(!")2 + m2"2 + g"3 + #"4

#

Need to go to canonical normalization !! eky0!

S4 =!

d4x (!")2 + m2e!2ky0"2 + ge!ky0"3 + #"4

All mass scales on IR brane got crunched by warp factor

Super-heavy IR brane Higgs becomes light!

An IR brane scalar

Page 136: Slac Summer Institute 2009

Can put all fields on IR brane...but just like low dimension operators get

scrunched, high dimension operators get enlarged!

Motivated putting SM fields in bulk except for the Higgs

UV Brane IR Brane

SM Gauge + Fermions

Higgs boson

Now have SM KK modes, but no KK parityResonances not evenly spaced either

Get light KK copies of right-handed top

Page 137: Slac Summer Institute 2009

Tonnes of Theory & Pheno and Models for RS Models!

AdS/CFTTheories in Anti-de Sitter space (RS metric)

Equivalent to 4D theories that are conformal (scale invariant)

5D description is way of mocking up complicated 4D physics!

Warping is Dimensional Transmutation

IR Brane is breaking of conformal symmetry

!IR = e!ky0!UV

!QCD = e!2!"!1

3 (MGUT)b0 MGUT

Page 138: Slac Summer Institute 2009

Technicolor TheoriesImagine there was no Higgs

QCD still gets strong and quarks condense

!QQc" #= 0 Qc = (U c, Dc)

QQc ! (1, 2) 12

Condensate has SM gauge quantum numbers

Like the Higgs!QCD confinement/chiral symmetry breaking

breaks electroweak symmetry

Technicolor is a scaled-up version of QCDRS Models are the modern versions of Technicolor

Page 139: Slac Summer Institute 2009

In Technicolor theoriesNot necessarily a Higgs boson

Technirhos usually first resonance

OS =H†Wµ!HBµ!

!2

Mediate contributions to

! >! 3 TeVwithW±, Z0

!T

!T

90 GeV

800 GeV

etcNeed to be lighter than 1 TeV

Page 140: Slac Summer Institute 2009

In Technicolor theoriesNot necessarily a Higgs boson

Technirhos usually first resonance

OS =H†Wµ!HBµ!

!2

Mediate contributions to

! >! 3 TeVwithW±, Z0

!T

!T

90 GeV

800 GeV

etcNeed to be lighter than 1 TeV

W±, Z0

!T!T

90 GeV

3 TeV

etc

Can push off the Technirhosusually a scalar resonance becomes narrow

600 GeV !T

!T starts playing the role of the HiggsRequires assumptions about

technicolor dynamics

Would like to get scalars lightwithout dynamical assumptions

Page 141: Slac Summer Institute 2009

Higgs as a Goldstone boson!T !" "T

Higgs boson is a technipion

Pions are light because the areGoldstone bosons of approximate symmetries

V (!T ) ! m2f2 cos !T /f

f set by Technicolor scale

!!T " = 0,!f

Goldstone bosons only have periodic potentials

Page 142: Slac Summer Institute 2009

Little Higgs TheoriesSpecial type of symmetry breaking

V (!T ) ! f4 sin4 !T /f + m2f2 cos !T /f

Looks like normal “Mexican hat” potential

Lots of group theory to get specific examples

Page 143: Slac Summer Institute 2009

Little Higgs TheoriesSpecial type of symmetry breaking

V (!T ) ! f4 sin4 !T /f + m2f2 cos !T /f

Looks like normal “Mexican hat” potential

Lots of group theory to get specific examples

[SU(3)! SU(3)/SU(3)]4SU(5)/SO(5)

SU(6)/Sp(6) [SO(5)! SO(5)/SO(5)]4

[SU(4)/SU(3)]4SU(9)/SU(8)

SO(9)/SO(5)! SO(4)

Page 144: Slac Summer Institute 2009

All have some similar features

New gauge sectors

Vector-like copies of the top quarksQ3 & Qc

3 U c3 & U3

There are extended Higgs sectors SU(2)L singlets, doublets & triplets

Page 145: Slac Summer Institute 2009

Conclusion

Beyond the Standard Model Physics is rich and diverse

Within the diversity there are many similar themes

These lectures were just an entry way into the phenomenology of new physics

We’ll soon know which parts of these theorieshave something to do with the weak scale

Page 146: Slac Summer Institute 2009

References

S. P. Martin

hep-ph/9709356

C. Csaki et al

“Supersymmetry Primer”

“TASI lectures on electroweak symmetry breaking from extra dimensions”hep-ph/0510275

M. Schmaltz, D. Tucker-Smith“Little Higgs Review”

hep-ph/0502182

I. Rothstein

hep-ph/0308286“TASI Lectures on Effective Field Theory”

G. Kribs“TASI 2004 Lectures on the pheomenology of extra dimensions”

hep-ph/0605325

J. Wells

hep-ph/0512342“TASI Lecture Notes: Introduction to Precision Electroweak Analysis”

R. Sundrum“TASI 2004: To the Fifth Dimension and Back”

hep-ph/0508134