Extra Dimensions at the LHC Nobuhito Maru (Chuo Univ.) 7/23/2010 - - PowerPoint PPT Presentation

extra dimensions at the lhc
SMART_READER_LITE
LIVE PREVIEW

Extra Dimensions at the LHC Nobuhito Maru (Chuo Univ.) 7/23/2010 - - PowerPoint PPT Presentation

Extra Dimensions at the LHC Nobuhito Maru (Chuo Univ.) 7/23/2010 Workshop@YITP ( ) LHC


slide-1
SLIDE 1

Extra Dimensions at the LHC

Nobuhito Maru

(Chuo Univ.) 7/23/2010 Workshop@YITP

slide-2
SLIDE 2

このトークの目的

(世話人からのリクエスト)

“LHCで新しい物理が発見される前夜の今の時代に

どういう高次元模型があり、 どのような将来性があり、 どのような特徴があるのか、 高次元理論からの実験的予言とは どのようなものがあるのか、

など高次元理論のオーバーヴュー”

slide-3
SLIDE 3

Introduction

slide-4
SLIDE 4

Now LHC is working!!

slide-5
SLIDE 5
slide-6
SLIDE 6

One of the guiding principles to go beyond the SM

⇒ hierarchy problem

Dynamics: Technicolor Symmetry: Supersymmetry

The purpose of LHC is to search for NEW PHYSICS as well as Higgs hunting

MW << MP

slide-7
SLIDE 7

One of the guiding principles to go beyond the SM

⇒ hierarchy problem

Dynamics: Technicolor Symmetry: Supersymmetry Geometry: Extra Dimensions

The purpose of LHC is to search for NEW PHYSICS as well as Higgs hunting

MW << MP

slide-8
SLIDE 8

Step 1: Looking for a new particle “X” with coupling to the SM fields Step 2: Identify the most promising production processes for X (QCD processes are better) Step 3: Calculate σ(pp→X) Step 4: (1) X is stable (a) EM charged → X behave like μ (b) Color charged → X hadronized (many BKGs) (c) Weakly charged → X like ν as missing energy (2) X is unstable ⇒ decay to the SM fields (coloress processes are better) Compute the branching ratio Step 5: Compute σ(SM background processes)

General strategy of collider physics

slide-9
SLIDE 9

Best way

Production from color particles + Decay to colorless states

g g

l + l + l − l −

Z Z X

slide-10
SLIDE 10

In this talk, we discuss collider signatures of various models based on extra dimensions We introduce basic ideas of each model, and does not discuss the model in detail Off course, we cannot cover all signatures, so focus on the model independent ones

slide-11
SLIDE 11

Plan

1: Introduction 2: KK Graviton Large Extra Dimensions Warped Extra Dimension Black Holes 3: Universal Extra Dimensions 4: Gauge-Higgs Unification 5: Higgsless Models 6: Higgs 7: Radion 8: Summary

slide-12
SLIDE 12

KK Graviton

“Indirect Collider Signals for Extra Dimensions” J.L. Hewett, PRL82 (1999) 4765 “Quantum Gravity and Extra Dimensions at High-Energy Colliders” G.F. Giudice, R. Rattazzi & J.D. Wells, NPB544 (1999) 3 “Searching for the Kaluza-Klein Graviton in Bulk RS Models” A.L. Fitzpatrick, J. Kaplan, L. Randall & L.T. Wang JHEP 0709 (2007) 013 “Warped Gravitons at the CERN LHC and Beyond”

  • K. Agashe, H. Davoudiasl, G. Perez & A. Soni, PRD76 (2007) 036006
slide-13
SLIDE 13

Large Extra Dimensions

“The Hierarchy Problem and New Dimensions at a Milimeter”

  • N. Arkani-Hamed, S. Dimopoulos and G. Dvali

PLB429 (1998) 263

slide-14
SLIDE 14

( ) ( ) ( ) ( )

2

4 4 4 4 2 4 2 4 * * 1 2 2 *

1 1 2 2 1 2

P

n n n n n n M n P n

S M d x g M V d x g M R M π

+ + + + + +

= − − = − −   ⇒ =    

∫ ∫

     R R

n = 1 n = 2 n = 3 : n = 6 # of XD

R

10^12 m 1 mm 10 nm : 10^-11 m Excluded

(No deviations up to 200 μm)

(4+n)-dim gravity compactified on n-dim compact space

(SM fields are confined on 3-brane)

Lowering the higher dim. Mp to TeV by large extra dimensions to solve the hierarchy problem (n-dim torus)

*

1 M TeV =

If

slide-15
SLIDE 15

Signatures for KK gravitons 1: Virtual graviton exchange

g

l + l −

( )

2 2

1

n P

T P T M s n R

µνρσ µν ρσ

= −

( ) ( )

4 2 1 *

,

n n

h x y T x d xd y M

µν µν +

Spin sum of the polarization tensors

Log div. for n=2 Power div. for n > 2 Cutoff by the string scale MS λ:O(1) constant

g

( )

n

G

slide-16
SLIDE 16

ADD contributions to the Drell-Yan process@LHC SM prediction

Hewett (1999)

Ms = 2.5 TeV Ms = 4.0 TeV

slide-17
SLIDE 17

2: Real graviton emission → Missing energy

T

pp jet E → +

( )

n

qg qG →

( )

n

qq gG →

( )

n

gg gG →

Dominant process

slide-18
SLIDE 18

Giudice, Rattazzi & Wells (1999)

( )

T

qq Z jet g jet E → + → +

( )

νν

2

ˆ ˆ : , :

D

a s M b all s <

c.o.m. energy in the parton collision

slide-19
SLIDE 19

Giudice, Rattazzi & Wells (1999)

( )

T

qq Z jet g jet E → + → +

( )

νν

2

ˆ ˆ : , :

D

a s M b all s <

slide-20
SLIDE 20

Warped Extra Dimension

“A Large Mass Hierarchy from a Small Extra Dimension”(RS1) “An Alternative to Compactification”(RS2)

  • L. Randall and R. Sundrum

PRL83 (1999) 3370; PRL83 (1999) 4690

slide-21
SLIDE 21

RS1

Higgs SM Planck TeV

2 2 2 ky

ds e dx dx dy

µ ν µν

η

= +

( )

[ ]

( ) (

)

( )

( )

( ) (

)

( )

2 † 4 2 † exp 4 exp[2 ] 2 † 4 † exp[ ]

2

12 1 1 2 2 1 1 2 2

P Higgs M kR kR k H H kR R

TeV if kR S y R d x g g D H D H m H H y R d x D H D H m H e H

µν µν µ ν π π η µ ν π π

δ π δ π

→ − −

≈     = − − −          → − −        

∫ ∫

   

O

0 mode graviton

Trancated AdS5

Lowering the Planck scale by the warp factor KK gravitons

slide-22
SLIDE 22

Bulk SM in RS

Higgs Planck TeV

0 mode graviton

To address the flavor physics, the SM fields except Higgs are in the bulk

Agashe, Delgado, May & Sundrum (2003)

(t, b)L

1st ,2nd generations bR

tR

KK gravitons

slide-23
SLIDE 23

Higgs Planck TeV

0 mode graviton

tR

KK gravitons

1st ,2nd generations bR KK gravitons & (right-handed)top are localized on TeV brane ⇒ they are strongly coupled

(t, b)L

( )

( )

1

gg G tt → → RS

slide-24
SLIDE 24

All coupling to the KK gravitons can be written as

4 XXG XX

C d xh T µν

µν

(XX: a pair of fermions or gauge fields)

( ) ( )

( )

( ) ( ) ( ) ( )

( )

4 1 2 2 2 † 1 2 4 2 1 1 2 1 † 101 5 2 1 1 2 4

1 2 2 3.83 1 1 2 3.83 1 2 1 2 1 1

c c XX XXG ssG ffG kr ffG kr

XX T C ss C M L TeV dyy J y ff i D C M L TeV J y e J x tt i D C dyy M L TeV e

µν µ ν ν µ ν π ν ν µ ν ν π ν

φ φ ν ψ σ ψ ν ψ σ ψ

+ − + − + − +

∂ ∂ = +   =   −   + = −

∫ ∫

( ) ( )

( ) ( ) ( ) ( ) ( ) ( )

2 2 1 2 1 1 2 2 2 4 2 4

3.83 3.83 3.83 1 0.47 3.83

L L ggG c c

y J y J y J x dyy J y gg F F C kr M L TeV J y kr M L TeV

ν ν µρ ν ρ

π π

− +

= ≈

slide-25
SLIDE 25

Cross section of KK graviton production

Fitzpatrick, Kaplan, Randall & Wang (2007)

gg -> G

qq -> q’q’WW -> q’q’G M4=2.5k

slide-26
SLIDE 26

Branching ratios for KK graviton decay 1

G tt →

: dominant mode

Background: t tbar from the SM KK gluon -> t tbar etc

slide-27
SLIDE 27

1

gg G tt → →

Discovery reach

Fitzpatrick, Kaplan, Randall & Wang (2007)

slide-28
SLIDE 28

( )

( )

1

4 ,

L L

gg G Z Z l l e µ → → → =

k/MP = 0.5, 1.0, 1.5, 2.0 from bottom to top Agashe, Davoudiasl, Perez & Soni (2007)

slide-29
SLIDE 29

( )

( )

1

4 ,

L L

gg G Z Z l l e µ → → → =

k/MP = 0.5, 1.0, 1.5, 2.0 from bottom to top Agashe, Davoudiasl, Perez & Soni (2007)

1st KK graviton up to around 2TeV can be seen

slide-30
SLIDE 30

Black Hole

“Black Holes at the Large Hadron Collider”

  • S. Dimopoulos & G. Landsberg

PRL87 161602 (2001) “High Energy Colliders as Black Hole Factories: The End of Short Distance Physics” S.B. Giddings & S. Thomas PRD65 056010 (2002)

slide-31
SLIDE 31

Production

( ) ( )

( )

( )

2 1 2 2 * *

8 3 2 1 2

n BH BH S

n M M R M M n σ π

+

    Γ + ≈ =       +      

S

R

Two partons with moving in opposite directions

ˆ

BH

s M =

If the impact parameter < RS, a BH with MBH forms

Total cross section

*

M ≈ TeV

with ⇒ BH production/year!!

1 / −

30fb y

7

10

(comparable to Z production@LEP)

(Schwarzshild radius)

slide-32
SLIDE 32

Decay

BHs, once produced, evapolate @Hawking temp.

1 100 4

H S

n T GeV R π + = ≈

BH decay to SM particles with rough equal probability:

G, q: 72%, l: 11%, Z, W: 8%, ν, graviton: 6%, H: 2%, γ: 1%

slide-33
SLIDE 33

# of BHs produced @LHC in e or γ decay channel with 100 fb^-1 of integrated luminosity The shaded regions -> events for n = 2-7 SM bkg from Z(ee) + jets & γ+ jets SM bkg from Z(ee) + X

slide-34
SLIDE 34

Universal Extra Dimension

“Bounds on Universal Extra Dimensions”

  • T. Appelquist, H-C. Cheng & B. Dobrescu

PRD64 035002 (2001)

slide-35
SLIDE 35

Universal Extra Dimension (UED) model is just a higher dim. extension of the Standard Model ↓ All of the SM fields propagate in extra dimensions of size 1/R ~ TeV

(In ADD & RS, some or all of them are confined to 3-brane)

Motivations for UED (although not a solution of

the hierarchy problem…)

1: KK parity

KK parity which is a remnant of KK momentum is conserved even after orbifold (-1)^n

  • ex. Reflection symmetry w.r.t. the center of

line segment for S^1/Z2 orbifold

slide-36
SLIDE 36

☆KK parity relaxes the constraints from EWPT ⇒ 1/R > 300 GeV (5D on S^1/Z2) testable @colliders

Appelquist, Cheng & Dobrescu (2001)

☆KK parity naturally predicts a candidate of dark matter “lightest KK particle (LKP)” like a LSP in SUSY w/ R-parity ∵ 1st KK modes are always produced in pairs

2: # of generations from anomaly cancellation (6D)

Dobrescu & Poppitz (2001)

3: Proton stability by Lorentz subgroup (6D)

Appelquist, Dobrescu, Ponton & Yee (2001)

2 8 2

Z T Z ⊂

Witten anomaly:

( )

( )

( ) ( )

6

2 2 2 0 mod6 0 mod3

g W

SU N N n

+ −

Π = − = = ⇒

slide-37
SLIDE 37

Decays & products of 1st KK modes (5D on S^1/Z2)

LKP

Dominant transition Rare transition (Q,L): SU(2)L doublet (q,l): SU(2)L singlet

slide-38
SLIDE 38

Excluded by CDF Discovery reach for 5D UED in Q1Q1 -> 4l + missing energy

slide-39
SLIDE 39

Gauge-Higgs Unification

“LHC Signals for Coset Electroweak Gauge Bosons in Warped/Composite PGB Higgs Models”

  • K. Agashe, A. Azatov, T. Han, Y. Li, Z-G. Si & L. Zhu

PRD81 096002 (2010)

slide-40
SLIDE 40

Mass term is forbidden by the gauge symmetry Higher dimensional Lorentz invariance

Higher dimensional gauge symmetry

Identified with Higgs in the SM

Gauge-Higgs unification Higgs potential is generated @1-loop and finite due to the higher dim. gauge symmetry

EW scale is stabilized

Ay ⇔ Aμ

slide-41
SLIDE 41

Gauge symmetry breaking: by an orbifold (ex. S^1/Z2)

( ) ( )

2 1 G H SU U → ⊇ ×

Parity assignments of gauge sector

( ) ( ) ( ) ( ) ( ) ( )

H H H y H H H y y y

A y A y A y A y A y A y

µ µ µ

  ∂ = − =   ⇔   − = − =    

( ) ( ) ( ) ( ) ( ) ( )

G H G H G H G H G H G H y y y y

A y A y A y A y A y A y

µ µ µ

  − = − =   ⇔   − = ∂ =    

H subgroup G/H coset

: :

H G H y

A A

µ

SU(2) x U(1) Gauge fields

Higgs

Only even mode has a massless mode Model independent new fields ⇒ SU(2) doublet coset gauge boson partner of Higgs

G H

slide-42
SLIDE 42

( )

1 C C

pp W t pp W t

± ±

→ → vs

slide-43
SLIDE 43

( )

1 C C

pp W t pp W t

± ±

→ → vs

We focus on the low mass region of ∵our goal is to explore the reach of discover of WC

( )

1

t

M

slide-44
SLIDE 44

Dominant channels of WC production & its decay

( ) ( ) ( )

1 1 1 C

bg W t bt t → →

b b

( )

1

t

g

( )

1

t

C

W

( )

1

t

( )

( )

( )

( )

( )

( ) ( )

( )

( )

( )

( )

( )

( )

( ) ( ) ( )

( )

( )

( )

( )

( )

( )

2 2 1 1 1 1 1 2 2 2 1 1

1:3 2 5 90% 50% 22.5% 2: 7 2 , 2 90% 50% 45% 3: 9 , 90% 50% 22.5%

C C C

b W l jets Br W t b Br t bW bbWtH Z l jets Br W t b Br t bW Br t tH tZ btH Z tH Z l jets Br W t b Br t tH tZ ν ν ν  + → +   → × → ≈ × =   → +   → × → × → × →    ≈ × × =  → +    → × → ≈ × = 

( )

( )

1

bW t tH tZ   →   

slide-45
SLIDE 45

14 s TeV =

slide-46
SLIDE 46

(3 events) (5 events) (15 events)

14 s TeV =

slide-47
SLIDE 47

Higgsless Models

“Collider Phenomenology of the Higgsless Models”

  • A. Birkedal, K. Matchev & M. Perelstein,

PRL94 191803 (2005)

slide-48
SLIDE 48

SU(2) x U(1) -> U(1)em by BCs without a Higgs boson???

Higgsless model??? In extra dimensions, the gauge symmetry can be broken by BCs ⇒ New possibility Immediate question: How unitarizes W/Z scattering amplitudes without Higgs???

slide-49
SLIDE 49

(Warped) Model Planck TeV

2 2 2 ky

ds e dx dx dy

µ ν µν

η

= +

AdS5 on an interval

Csaki, Grojean, Pilo & Terning (2003)

SU(2)L x U(1)B-L

U(1)y SU(2)L x SU(2)R

SU(2)D

( )

3 5 5 3 5 5 5 R R R

A g B g A g B g A

µ µ µ µ µ ± =

′ − = ′ ∂ + =

( )

5 La Ra La Ra

A A A A

µ µ µ µ

− = ∂ + =

SU(2)L x SU(2)R x U(1)B-L → U(1)em

slide-50
SLIDE 50

L L L L

W Z W Z

± ±

W W W W W W

Z Z Z Z Z Z

W W

( ) ( ) ( )

( )

2 2 2 4 2 4 n n n n

E E M A E M E A A M M     +           = + +     ฀ A O

slide-51
SLIDE 51

L L L L

W Z W Z

± ±

W W W W W W W W W W

Z Z Z Z Z Z Z Z Z Z

W W

( )

n

W

( )

n

W

( ) ( ) ( )

( )

2 2 2 4 2 4 n n n n

E E M A E M E A A M M     +           = + +     ฀ A O

slide-52
SLIDE 52

( )

( )

( ) ( )( )

( )

( )

( )

( )

( )

( )

( )

( )

2 2 4 4 2 2 2 2 2 2 2 2 2 2 2 2

2 3

n n

WWZZ WWZ WZW n Z WWZZ WWZ W Z WWZ W Z W n W WZW n n W

g g g E M g g M M g M M M g M E M

± ±

= + ← = − + +   −   = − ← =      

∑ ∑

O O Necessary conditions for unitarity

This sum rule can be satisfied by only the 1st KK mode in a good approximation

( )

( )

1

2 1

3

WWZ Z WZW W W

g M g M M

±

These sum rules are automatically satisfied by higher dimensional gauge invariance

slide-53
SLIDE 53

Check this rule by measuring and

( )

1

WZW

g

( )

1 W

M

±

( ) ( )

2 1 1

3

WWZ Z WZV W W

g M g M M

±

( )

( )

( )

1

1

0.04 700

WZW W

g M GeV CDF

±

≤ ≥ for

( )

1

3 W W Z l ν

± ±

→ → +

“gold-plated” events

L

W ±

L

W ±

L

Z

L

Z

q l ± ν

l +

l −

( )

1

W

±

q q′′ q′

(Independent of model-building details)

slide-54
SLIDE 54

Check this rule by measuring and

( )

1

WZW

g

( )

1 W

M

±

( ) ( )

2 1 1

3

WWZ Z WZV W W

g M g M M

±

( )

( )

( )

1

1

0.04 700

WZW W

g M GeV CDF

±

≤ ≥ for

( )

1

3 W W Z l ν

± ±

→ → +

“gold-plated” events

L

W ±

L

W ±

L

Z

L

Z

q l ± ν

l +

l −

( )

1

W

±

q q′′ q′

(Independent of model-building details)

slide-55
SLIDE 55

Check this rule by measuring and

( )

1

WZW

g

( )

1 W

M

±

( ) ( )

2 1 1

3

WWZ Z WZV W W

g M g M M

±

( )

( )

( )

1

1

0.04 700

WZW W

g M GeV CDF

±

≤ ≥ for

( )

1

3 W W Z l ν

± ±

→ → +

“gold-plated” events

L

W ±

L

W ±

L

Z

L

Z

q l ± ν

l +

l −

( )

1

W

±

q q′′ q′

(Independent of model-building details)

( )

1

W

production cross sections @LHC

slide-56
SLIDE 56

# of events in the 2jet + 3l + ν channel

Discovery reach (10 events) 550 GeV (1 TeV) requires 10 (60) fb^-1 for 1-2 year

slide-57
SLIDE 57

Higgs

“Higgs Production from Gluon Fusion in Warped Extra Dimensions”

  • A. Azatov, M. Toharia & L. Zhu, arXiv:1006.5939

“Gauge-Higgs Unification at the CERN LHC”

  • N. Maru & N. Okada, PRD77 (2008) 055010

“Kaluza-Klein Effects on Higgs Physics in Universal Extra Dimensions” F.J. Petriello, JHEP05 (2002) 003

slide-58
SLIDE 58
slide-59
SLIDE 59

Discovery Mode

slide-60
SLIDE 60

Discovery Mode

2γ decay is a promising mode for mH < 140GeV and well studied

slide-61
SLIDE 61

g g γ γ

( )

n

t

( ) ( )

n n

t W

H

gg -> H -> γγ

Model information

, ,

,

t W t W n

y g m

slide-62
SLIDE 62

GHU (5D SU(3))

mh = 120 GeV

14% deviation @m1 = 1 TeV nt = 1 nt = 3 nt = 5

periodic anti-periodic

← 1st KK mass SM

Maru & Okada (2007)

slide-63
SLIDE 63

Petriello, JHEP05 (2002) 003

UED (5D)

1/R = 500 GeV 1/R = 750 GeV 1/R = 1 TeV 1/R = 1.25 TeV, 1.5 TeV

Additive

SM

slide-64
SLIDE 64

RS with Bulk Higgs

×: 1/R’ = 5 TeV +: 1/R’ = 2 TeV △: 1/R’ = 1.5 TeV

1, 1

RS RS gg h h SM SM gg h h γγ γγ

σ σ σ σ

→ → → →

> <

Azatov, Toharia & Zhu, 1006.5939

mH = 120GeV

slide-65
SLIDE 65

×: 1/R’ = 5 TeV +: 1/R’ = 2 TeV △: 1/R’ = 1.5 TeV

RS with Brane Higgs

Sign cannot be predicted

Azatov, Toharia & Zhu, 1006.5939

mH = 120GeV

slide-66
SLIDE 66

Radion

“Graviscalars from Higher-Dimensional Metrics and Curvature-Higgs Mixing” G.F. Giudice, R. Rattazzi & J.D. Wells “Radion Phenomenology on Realistic Warped Space Models”

  • C. Csaki, J. Hubisz & S.J. Lee, PRD76 (2007) 125015
slide-67
SLIDE 67

( )

( ) ( )

( )

( )

( )

( )

2 2 2 2 2 2 2 2 1

1 2 1 2 1/

ky F F

ds e F dy R e dx dx F dz R k z R TeV z

µν µ ν µν

η η

− + − −

= − +   ′ = − + = < < =    

Radion is a scalar perturbation of the metric which cannot be gauged away

( )(

)

5 2 5 55 55

1 2 1 2

MN radion MN r

S d x gT g z d x g r x T T g R

µ µ

δ = −     = −     ′ Λ      

∫ ∫

Radion-Matter interaction

( ) ( ) ( ) ( )

2 2 2

1 6 , , 6

r r

r x R z z F z x r x TeV R R R R     = = Λ ≡ ≈     ′ ′ ′ Λ    

4D canonically normalized radion r(x) Localized on TeV brane

slide-68
SLIDE 68

( ) ( )

( )

, , L R UV UV IR IR L R L r r

m m c c r

  • thers

r t b ψ ψ ψ ψ − Λ Λ

( ) ( )

2 2 2 2 2 2

3 3 2 1 1 log 1 log

W Z W Z r r r r

M M kR M rW W kR M rZ Z

µ µ µ µ

    ′ ′ − + + − +     Λ Λ Λ Λ    

( ) ( )

( )

( ) ( )

1 4 4log 8

UV IR i i i i r

r b F F F kR

µν µν

πα τ τ α κ τ π   − +     − + −   ′   Λ    

Coupling to the SM fermions Coupling to massive gauge bosons (W, Z) Coupling to massless gauge bosons (γ, g) Brane kinetic term Trace anomaly 1-loop effects

slide-69
SLIDE 69

Bulk RS1 RS1 Λr = 2 TeV

Branching fraction of the radion

slide-70
SLIDE 70

Branching fraction of Higgs

slide-71
SLIDE 71

Bulk RS1 RS1 Λr = 2 TeV

Branching fraction of the radion

Very similar behavior to Higgs boson (Λr ⇔ v), but Br(r -> gg) can be enhanced by comparing to Br(H -> gg) by a factor “10” due to the radion coupling through the trace anomaly

slide-72
SLIDE 72

Ratio of gg -> r -> γγ/gg -> H -> γγ

Bulk RS1 RS1 SM

slide-73
SLIDE 73

Summary

Now, “Extra Dimensions” as an alternative to solution to the hierarchy problem is no longer alternative KK particles with TeV mass

These give rise to various collider signatures@LHC!!

Let Let us us ex expec ect tha that t the n the news ews of discovery o

  • f ex

extr tra di dimen ensions will c ll com

  • me soon
  • on!!

!!

slide-74
SLIDE 74

Backup

slide-75
SLIDE 75

KK Gluon

“The Bulk RS KK-gluon at the LHC”

  • B. Lillie, L. Randall & L-T. Wang, JHEP09 (2007) 074

“CERN LHC Signals from Warped Extra Dimensions”

  • K. Agashe, A. Belyaev, T. Krupovnicas, G. Perez & J. Virzi

PRD77 (2008) 015003

slide-76
SLIDE 76

Bulk SM in RS

Higgs Planck TeV

0 mode graviton

tR

KK gluons

1st ,2nd generations bR KK gluons and (right-handed) top are localized on IR brane ↓ KK gluons strongly couple to top

(t, b)L

slide-77
SLIDE 77

Wave function of 1st KK gluon

( )

( ) ( ) ( ) 1 1 1 1 1 k k k

m m e J e Y e k k

πφ πφ πφ

χ φ α       ∝ +                  

slide-78
SLIDE 78

Coupling of 1st KK gluon to zero mode fermion

( )

( )

1

3 2

1 0.8

ffA c SM c

g kr g kr π π

  +   ฀ O

UV localized IR localized Q3L tR

slide-79
SLIDE 79

Cross section for production of 1st KK gluon

slide-80
SLIDE 80

Branching ratio of 1st KK gluon

slide-81
SLIDE 81

Invariant mass distribution of

( )

1

g tt →

slide-82
SLIDE 82
slide-83
SLIDE 83

pp → jet + missing energy

Vacavant & Hinchliffe (2001)

slide-84
SLIDE 84

( ) ( ) ( )

, ,

s

e k s e k s P k

µν αβ µναβ

=

( )

( ) ( )

2 2 2

1 2 1 2 2 6 1 2

n n n

P k k k k k m m k k k k k k k k m

µναβ µα νβ µβ να µν αβ µν µ ν αβ α β µα ν β νβ µ α µβ ν α να µ β

η η η η η η η η η η η η = + −    + + +       − + + +

Spin sum of polarization tensors

slide-85
SLIDE 85

Anomaly cancellation 6D Anomaly = One-loop Square diagram

SU(3)C

⇒ ⇒ Q ⇔ U, D

Opposite chirality

Gravitational

N+ = N-

Q+, U-, D-, L-, E+, N+ & (+ ⇔ -) Q+, U-, D-, L+, E-, N- & (+ ⇔ -)

4 possibilities

Arkani-Hamed, Cheng, Dobrescu & Hall (2000) Dobrescu & Poppitz (2001)

( ) ( )

a b c d a b c d

Tr T T T T Tr T T T T

+ −

∑ ∑

slide-86
SLIDE 86

SU(2)W x U(1)Y sector

SU(2)W x U(1)Y anomalies cannot be canceled by the SM matter, but GS mechanism helps

[SU(2)W]^4, [U(1)Y]^4, [SU(2)W]^2[SU(3)C]^2, [SU(3)C]^2[U(1)Y]^2, [SU(2)W]^2[U(1)Y]^2 [SU(2)W]^3 = 0 (identically), [SU(3)C]^3U(1)Y = 0 (per generation) Global anomaly

Π6(G): nontrivial if G= SU(3), SU(2), G2 Π6[SU(3)]: trivial ∵ SU(3)C is vector-like SU(2)L: N(2+) - N(2-) = 0 mod 6 → ng [N(2+) - N(2-)] = 0 mod 6 ⇒ ng = 0 mod 3 [∵ N(Q)=3, N(L)=1]

slide-87
SLIDE 87

( ) ( )

( ) ( )

( ) ( ) ( ) ( )

( ) ( )

( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( )

3 2 2 4 4 4 4 4 2 2 2 2

1 2 1 2 2 1 3 (1) 3 6 3 3 6 3 3 1 4 1 2 4 1 1 3 1 3 3 36 9 9 36 9 9 2 6 16 3 3 2 1 136 243 95 1 1 6 3 3 2 216 54 1 1 3 2 3 2 3 2 2 2 3 2 1 2 36 SU U A Q A U A D A SU U C Q C U C D C C U SU SU C C C C SU U C   = + − = − + =           = − − = − − = −             × + + = + + + + = =     = = =         = ±        

( ) ( ) ( ) ( ) ( ) ( )

( )

( )

( )

( ) ( )

2 2 2 2

1 1 1 2 2 2 4 3 6 2 2 3 2 2 2 2 2 C C C SU SU C C C C = − = ± =        

  • r
  • r

Reducible anomalies

slide-88
SLIDE 88
slide-89
SLIDE 89
slide-90
SLIDE 90
slide-91
SLIDE 91

Discovery significance of gg -> r -> γγ

( ) ( ) ( ) ( ) ( ) ( )

3 1 3 3 1 3 3

2

EM

τ τ τ τ τ τ = = = =

slide-92
SLIDE 92

Discovery significance of gg -> r -> ZZ -> 4l

( ) ( ) ( ) ( ) ( ) ( )

3 1 3 3 1 3 3

2

EM

τ τ τ τ τ τ = = = =

slide-93
SLIDE 93 ( )

( )

( )

( )( )

( )

( )

( )

( )

( )

( )

( )

( ) 2 4 2 2 2 2 4 2 2 2 2 2 2 2 2 2

2 3

n WWZZ WWZ WZV n Z W n n Z WWZZ WWZ W Z WWZ WZV W n n W W

g g g A M M M g g M M g g M A M M

± ±

= + ← =   −   − + + = − ← =      

∑ ∑

( )

( )

( )

( ) (

)

2 2 2 2 2 2 2 2

4 3

i WWWW WWZ WW WWV i i WWWW W WWZ Z WWV i i

g g g g g M g M g M

γ

= + +   = +    

∑ ∑

Sum Rules

slide-94
SLIDE 94
slide-95
SLIDE 95
slide-96
SLIDE 96
slide-97
SLIDE 97
slide-98
SLIDE 98
slide-99
SLIDE 99

×: 1/R’ = 5 TeV +: 1/R’ = 2 TeV △: 1/R’ = 1.5 TeV

Azatov, Toharia & Zhu, 1006.5939

slide-100
SLIDE 100

Angular dependences of gg -> G(V,S) -> t tbar

slide-101
SLIDE 101

Branching fractions

( ) ( )

( )

( ) ( ) ( ) ( )

( ) ( )

( )

( )

1 1 1 1 2 3 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1

0.5 0.65 10 10 0.33 1 0.02 1 6 1 6 B g Q Q B g q q B Q W Q B q Z q B Q Z Q B q q B Q Q B W L B W L B Z B Z L L γ γ ν ν ν ν

± − − ± ± ± ± ±

→ ≈ → ≈ → ≈ → ≈ − → ≈ → ≈ → ≈ → = → = → = → ≈

slide-102
SLIDE 102
slide-103
SLIDE 103
slide-104
SLIDE 104
slide-105
SLIDE 105

( ) ( ) ( )

2 2 1 2 2 2 2 3 2

1 1 , , , 36 96 3 1 , 16

m S m S P P m S P

d d t m t m qq gG F qG gG F dt sM s s dt sM s s d t m gg gG F dt sM s s σ α σ α σ α     → = → =           → =    

slide-106
SLIDE 106

Total cross section

Differential Cross section

Hawking Temp. n=4 n=4 n=4

slide-107
SLIDE 107

Ratio of gg -> r -> ZZ-> 4l/gg -> H -> ZZ -> 4l

Bulk RS1 RS1

slide-108
SLIDE 108

Similar type of deviations from the SM are also seen in 1: SUSY model

Djouadi, PLB453 (1998) 101

2: Little Higgs model Han, Logan, McElrath & Wang, PLB563 (2003) 191 Common feature among GHU, SUSY & LH is that the quadratic divergence in mh^2 is canceled

This can be seen diagrammatically as follows

h h

Start with Higgs self-energy diagram with a relative minus sign

h h

Top

New particles

slide-109
SLIDE 109

Similar type of deviations from the SM are also seen in 1: SUSY model

Djouadi, PLB453 (1998) 101

2: Little Higgs model Han, Logan, McElrath & Wang, PLB563 (2003) 191 Common feature among GHU, SUSY & LH is that the quadratic divergence in mh^2 is canceled

This can be seen diagrammatically as follows

<h> h

Replace one of the Higgs by its VEV

h <h>

Top

New particles

slide-110
SLIDE 110

Similar type of deviations from the SM are also seen in 1: SUSY model

Djouadi, PLB453 (1998) 101

2: Little Higgs model Han, Logan, McElrath & Wang, PLB563 (2003) 191 Common feature among GHU, SUSY & LH is that the quadratic divergence in mh^2 is canceled

This can be seen diagrammatically as follows

<h> h

Attaching 2 gluon lines ⇒ gluon fusion diagram with a relative minus sign

<h> h

Top

New particles

slide-111
SLIDE 111

Bulk RS1 RS1 Branching fraction of the radion Λr = 2 TeV