Diphoton Decay Excess & 125GeV Higgs Boson

in Gauge-Higgs Unification

Nobuhito Maru (Osaka City University)

with Nobuchika Okada (University of Alabama)

8/30/2013 SUSY2013@ICTP Trieste

References�

Diphoton Decay Excess and 125GeV Higgs Mass in Gauge-Higgs Unification NM and Nobuchika Okada

PRD87 095019 (2013)�

Gauge-Higgs Unification at CERN LHC NM and Nobuchika Okada

PRD77 (2008) 055010�

H�Zγ in Gauge-Higgs Unification NM and Nobuchika Okada

arXiv: 1307.0291 (to appear in PRD) also�

PLAN ! Introduction

! A Model of GHU

! gg�H & H��� in GHU

! Higgs mass analysis

! A Comment on H�Z�

! Summary

Introduction

ATLAS: Status of SM Higgs searches, 4/7/2012

mγγ spectrum fit, for each category, with Crystal Ball + Gaussian for signal plus background model optimised (with MC) to minimize biases Max deviation of background model from expected background distribution taken as systematic uncertainty

Total after selections: 59059 events

Main systematic uncertainties

5.2 H ! ZZ 11

(GeV)!!m110 120 130 140 150S

/(S+B

) Wei

ghte

d E

vent

s / 1

.5 G

eV

0

500

1000

1500

DataS+B FitB Fit Component

"1±"2±

-1 = 8 TeV, L = 5.3 fbs-1 = 7 TeV, L = 5.1 fbsCMS

(GeV)!!m120 130

Eve

nts

/ 1.5

GeV

1000

1500Unweighted

Figure 3: The diphoton invariant mass distribution with each event weighted by the S/(S+ B)value of its category. The lines represent the fitted background and signal, and the colouredbands represent the ±1 and ±2 standard deviation uncertainties on the background estimate.The inset shows the central part of the unweighted invariant mass distribution.

Higgs boson was discovered!!�

Introduction

ATLAS: Status of SM Higgs searches, 4/7/2012

mγγ spectrum fit, for each category, with Crystal Ball + Gaussian for signal plus background model optimised (with MC) to minimize biases Max deviation of background model from expected background distribution taken as systematic uncertainty

Total after selections: 59059 events

Main systematic uncertainties

5.2 H ! ZZ 11

(GeV)!!m110 120 130 140 150S

/(S+B

) Wei

ghte

d E

vent

s / 1

.5 G

eV

0

500

1000

1500

DataS+B FitB Fit Component

"1±"2±

-1 = 8 TeV, L = 5.3 fbs-1 = 7 TeV, L = 5.1 fbsCMS

(GeV)!!m120 130

Eve

nts

/ 1.5

GeV

1000

1500Unweighted

Figure 3: The diphoton invariant mass distribution with each event weighted by the S/(S+ B)value of its category. The lines represent the fitted background and signal, and the colouredbands represent the ±1 and ±2 standard deviation uncertainties on the background estimate.The inset shows the central part of the unweighted invariant mass distribution.

Still unclear, the origin of Higgs ??�

Diphoton decay excess

σ/σSM = 1.57 ± 0.22(stat) + 0.24 − 0.18(syst)�

Hint for New Physics??�

Diphoton decay excess

σ/σSM = 1.57 ± 0.22(stat) + 0.24 − 0.18(syst)�In this talk, we show that the H�γγ excess can be

explained in gauge-Higgs unification (GHU)�

One of the problems in the Standard Model: Hierarchy Problem

�

= + + …

Quantum corrections to Higgs mass is sensitive to the cutoff scale of the theory

22

216Hmδ πΛ≈

Too large!! (Natural cutoff scale is

Planck scale or GUT scale)

Higgs W,Z,γ Top

Motivation to consider GHU�

In GHU, the SM Higgs is identified with the 5th component of the 5D gauge field

forbids a local Higgs mass term (A5)2

� No quadratic divergence, finite regardless of the nonrenormalizability

mA5

2 1

16π 2

1R2

A5 → A5 + ∂5ε x,x5( ) + i ε x,x5( ), A5

⎡⎣ ⎤⎦

Gauge trf.�

In the gauge-Higgs unification,

1: New structure in the Higgs sector 2: Coupling of new particles to Higgs boson

controlled by higher dimensional gauge invariance

Deviations from the SM predictions & Collider signatures specific to GHU

are expected!!

A Model of GHU�

L = − 12

Tr FMN F MN( ) +Ψ3i=1,2,3 iΓM DM − Md

iε y( )( )Ψ3i=1,2,3

+Ψ6i=1,2 iΓM DM − Mu

iε y( )( )Ψ6i=1,2 +Ψ

15iΓM DMΨ15

+Ψ10i=1,2,3 iΓM DM − Ml

iε y( )( )Ψ10i=1,2,3 ( )5,M iµγ γΓ =

Lagrangian

Boundary conditions: S1: Ψ(y+2πR) = ψ(y), Z2:Ψ(-y) = ±ψ(y)

5D SU(3) x U(1)’ model on S1/Z2

Aµ =

+,+( ) +,+( ) −,−( )+,+( ) +,+( ) −,−( )−,−( ) −,−( ) +,+( )

⎛

⎝

⎜⎜⎜⎜

⎞

⎠

⎟⎟⎟⎟

, A5 =

−,−( ) −,−( ) +,+( )−,−( ) −,−( ) +,+( )+,+( ) +,+( ) −,−( )

⎛

⎝

⎜⎜⎜⎜

⎞

⎠

⎟⎟⎟⎟

Scrucca, Serone, Silvestrini (2003), Cacciapaglia, Csaki, Park (2006)�

L = − 12

Tr FMN F MN( ) +Ψ3i=1,2,3 iΓM DM − Md

iε y( )( )Ψ3i=1,2,3

+Ψ6i=1,2 iΓM DM − Mu

iε y( )( )Ψ6i=1,2 +Ψ

15iΓM DMΨ15

+Ψ10i=1,2,3 iΓM DM − Ml

iε y( )( )Ψ10i=1,2,3 ( )5,M iµγ γΓ =

Lagrangian

Boundary conditions: (+,+) only has massless mode

Aµ =

+,+( ) +,+( ) −,−( )+,+( ) +,+( ) −,−( )−,−( ) −,−( ) +,+( )

⎛

⎝

⎜⎜⎜⎜

⎞

⎠

⎟⎟⎟⎟

, A5 =

−,−( ) −,−( ) +,+( )−,−( ) −,−( ) +,+( )+,+( ) +,+( ) −,−( )

⎛

⎝

⎜⎜⎜⎜

⎞

⎠

⎟⎟⎟⎟

(+,+): cos(ny/R) (-,-): sin(ny/R)

SU(3) x U(1)’� SU(2) x U(1)Y x U(1)X

5D SU(3) x U(1)’ model on S1/Z2 Scrucca, Serone, Silvestrini (2003), Cacciapaglia, Csaki, Park (2006)�

L = − 12

Tr FMN F MN( ) +Ψ3i=1,2,3 iΓM DM − Md

iε y( )( )Ψ3i=1,2,3

+Ψ6i=1,2 iΓM DM − Mu

iε y( )( )Ψ6i=1,2 +Ψ

15iΓM DMΨ15

+Ψ10i=1,2,3 iΓM DM − Ml

iε y( )( )Ψ10i=1,2,3 ( )5,M iµγ γΓ =

Lagrangian

Boundary conditions: (+,+) only has massless mode

Aµ =

+,+( ) +,+( ) −,−( )+,+( ) +,+( ) −,−( )−,−( ) −,−( ) +,+( )

⎛

⎝

⎜⎜⎜⎜

⎞

⎠

⎟⎟⎟⎟

, A5 =

−,−( ) −,−( ) +,+( )−,−( ) −,−( ) +,+( )+,+( ) +,+( ) −,−( )

⎛

⎝

⎜⎜⎜⎜

⎞

⎠

⎟⎟⎟⎟

(+,+): cos(ny/R) (-,-): sin(ny/R)

0 mode of A5 = SM Higgs �

5D SU(3) x U(1)’ model on S1/Z2 Scrucca, Serone, Silvestrini (2003), Cacciapaglia, Csaki, Park (2006)�

Electroweak symmetry breaking

SU(2)LxU(1)Y�U(1)em

is radiatively triggered by nonzero <A5>

(Hosotani mechanism)�

3 = 2L1/6(Q) + 1L-1/3 2R1/6 + 1R-1/3(dR)

6* = 3L-1/3 + 2L1/6(Q) + 1L2/3 3R-1/3 + 2R1/6 + 1R2/3(uR)

10 = 4L1/2 + 3L0 + 2L-1/2(L) + 1L-1 4R1/2 + 3R0 + 2R-1/2 + 1R-1(eR)

15* = 5L-4/3 + 4L-5/6 + 3L-1/3 + 2L1/6(Q) + 1L2/3 5R-4/3 + 4R-5/6 + 3R-1/3 + 2R1/6 + 1R2/3(tR)

Fermion matter content�

Down quark sector (d, s, b)�

Up quark sector (u,c)�

Charged lepton Sector (e, µ, τ)�

Top quark�

Unwanted massless exotics (blue reps) & a half of extra Qs must be massive by brane localized mass terms�

Scrucca, Serone, Silvestrini (2003), Cacciapaglia, Csaki, Park (2006)�

3 = 2L1/6(Q) + 1L-1/3 2R1/6 + 1R-1/3(dR)

6* = 3L-1/3 + 2L1/6(Q) + 1L2/3 3R-1/3 + 2R1/6 + 1R2/3(uR)

10 = 4L1/2 + 3L0 + 2L-1/2(L) + 1L-1 4R1/2 + 3R0 + 2R-1/2 + 1R-1(eR)

15* = 5L-4/3 + 4L-5/6 + 3L-1/3 + 2L1/6(Q) + 1L2/3 5R-4/3 + 4R-5/6 + 3R-1/3 + 2R1/6 + 1R2/3(tR)

Down quark sector (d, s, b)�

Up quark sector (u,c)�

Charged lepton Sector (e, µ, τ)�

Unwanted massless exotics (blue reps) & a half of extra Qs must be massive by brane localized mass terms�

Top quark�

Fermion matter content�Scrucca, Serone, Silvestrini (2003), Cacciapaglia, Csaki, Park (2006)�

gg�H & H��� in GHU

Higgs production

Gluon fusion�

Decay rate of Higgs boson

Leff = Cgg

KK hGaµνGµνa

CggKKtop =

α S

8πv23

∂∂lnv

ln mn + mt( ) + ln mn − mt( )⎡⎣ ⎤⎦n=1

∞

∑

= α S

12πvmt

mn + mt

−mt

mn + mt

⎡

⎣⎢

⎤

⎦⎥

n=1

∞

∑

≅ −α S

12πv2

mt2

mn2

n=1

∞

∑ mt2 mn

2( ) = −α S

12πv13πmt R( )2

KK mode contributions: gg � H

KK top

log∞ - log∞ = finite�

Opposite sign to SM � destructive�

mn=n/R�

Leff = Cγγ

KK hF µν Fµν

CγγKKtop =

α em

6πv43

∂∂lnv

ln mn + mt( ) + ln mn − mt( )⎡⎣ ⎤⎦n=1

∞

∑

≅ −2α em

9πv13πmt R( )2

CγγKKW =

α em

8πv−7( ) ∂

∂lnvln mn + mW( ) + ln mn − mW( )⎡⎣ ⎤⎦

n=1

∞

∑

≅ +7α em

8πv13πmW R( )2

KK mode contributions: H � γγ

Opposite sign to SM�

KK top�

KK W�

Opposite sign to SM�

�

1500 2000 2500 3000 3500 40000.90

0.92

0.94

0.96

0.98

1.00

MKK!GeV

R !"R ##

(gg � H � γγ)GHU/(gg � H � γγ)SM�

Destructive�NM & N.Okada (2008)�

Diphoton decay excess

σ/σSM = 1.57 ± 0.22(stat) + 0.24 − 0.18(syst)�

Extension is required�

One of the simplest extensions: “extra leptons”

(colored particles greatly affect the gluon fusion)�

Two examples: 10, 15 plets of SU(3) with bulk mass & half-periodic BC ψ(y+2πR) = −ψ(y) �

No unwanted massless fermions

1st KK mass = 1/(2R) � Higgs mass �Helpful to adjust 125 GeV Higgs�

Contributions of KK leptons to H�γγ constructive

CγγSM < 0 & Cγγ

10,15 < 0 � Cγγ10,15/Cγγ

SM > 0�

NM & N.Okada, PRD87 (2013) 095019�

1500 2000 2500 3000 3500 40001.0

1.1

1.2

1.3

1.4

1.5

MKK!GeV

R

1500 2000 2500 3000 3500 40000.9

1.0

1.1

1.2

1.3

1.4

1.5

MKK!GeV

R

R =σ gg→ H( )GHU+10 × BR H →γγ( )GHU+10

σ gg→ H( )SM × BR H →γγ( )SM

R =σ gg→ H( )GHU+15 × BR H →γγ( )GHU+15

σ gg→ H( )SM × BR H →γγ( )SM

10Q = −1M = 0.55 R

⎛⎝⎜

⎞⎠⎟

15Q = −5M = 0.85 R

⎛⎝⎜

⎞⎠⎟

!4 !2 0 2 40.9

1.0

1.1

1.2

1.3

1.4

1.5

1.6

1.7

Q

R !"R ##

!6 !4 !2 0 2 4 60.9

1.0

1.1

1.2

1.3

Q

R !"R ##

10

15

1/R = 3TeV fixed�

R =σ gg→ H( )GHU × BR H →γγ( )GHUσ gg→ H( )SM × BR H →γγ( )SM

Higgs mass analysis�

Higgs mass analysis by 4D EFT approach�

Instead of 5D Higgs potential minimization,

solve 1-loop RGE for Higgs quartic coupling λ by imposing BC λ=0@1/R “gauge-Higgs condition” Haba, Matsumoto, Okada & Yamashita (2006, 2008) �

Natural realization of GHU in 4D viewpoint:

VH = 0 above 1/R by 5D gauge invariance

Furthermore, NO vacuum instability�

This approach greatly simplifies Higgs mass study

In GHU, mH likely to be small loop generated�

1000 2000 3000 40000.00

0.05

0.10

0.15

0.20

0.25

0.30

!!GeV

"Numerical results for 1-loop RGE of ��

SM�SM +15�SM

+10�

MH = 125 GeV (λ=0.258)�

1/R�

M = 0.85R

No instability�

M = 0.55R

A Comment on H�Z��

NM & N.Okada, 1307.0291 (to appear in PRD)�

KK modes have electroweak charges

� Naturally expect deviation of Zγ decay from the SM

prediction�

Model dep. Correlation btw γγ & Zγ is interesting�

Our result is very striking!!�No KK mode contributions to Z� decay@1-loop�

A Comment on H�Z��

Simple reason: in the mass eigenstates, H and γ couples to KK modes with same mass eigenstates, but Z does not�

Z µγ ν Wµ+

n( ),Wµ− n( )( ) 0 −i

i 0⎛⎝⎜

⎞⎠⎟W+

±ν n( )

W−±ν n( )

⎛

⎝⎜

⎞

⎠⎟ + 2Zµγ

µ Wν+ n( ),Wν−

n( )( ) 0 i−i 0

⎛⎝⎜

⎞⎠⎟W+

±ν n( )

W−±ν n( )

⎛

⎝⎜

⎞

⎠⎟

Zµ Wµν+ n( ),Wµν−

n( )( ) 0 i±i 0

⎛

⎝⎜⎞

⎠⎟Wν+

± n( ),Wν−± n( )( )

Wµ±n( ) :n R ±mW ,Wµν ≡ ∂µWν − ∂νWµ

ψ 0n( ),ψ +

n( ),ψ −n( )( )

2γ µ 3 Wµ+ Wµ

+

Wµ− −γ µ 3 −Zµ

Wµ− −Zµ −γ µ 3

⎛

⎝

⎜⎜⎜⎜

⎞

⎠

⎟⎟⎟⎟

γ µ

ψ 0n( )

ψ +n( )

ψ −n( )

⎛

⎝

⎜⎜⎜

⎞

⎠

⎟⎟⎟,ψ 0,±

n( ) : nR, nR±mf

Fermion coupling�

ZWnWn

coupling�

ZγWnWn

coupling�

No H-Z-� coupling@1-loop found�

Summary

●We calculated KK mode contributions to gg � H & H � γγ @LHC in 5D SU(3)xU(1)’ GHU

●Especially, H � γγ excess (R=1.5-2.0) is focused as a sign of New Physics

●Minimal model cannot explain the excess (NM & Okada)

●Extra leptons can enhance H�γγ as we like by adjusting U(1)’ charges

ex. 10 & 15 plets of SU(3) w/ bulk mass & half-periodic BC

●These leptons also helps to enhance Higgs mass

Summary ● 1-loop RGE analysis of Higgs quartic coupling with GH condition λ=0@MKK

� 10 with M=0.55/R, 15 with M=0.85/R � 125 GeV Higgs � No instability

● Extra leptons are (some kind of) Z2 odd & stable due to the half-periodic BC

� lightest KK leptons with 1�3 TeV mass can be DM candidate in case of vanishing electric charge

● No KK mode contribution to H�Zγ@1-loop

Thank you very much

for your attention�