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Higgs Phenomenology in a Simple Model with VectorResonances
Alfonso R. Zerwekh
Universidad Técnica Federico Santa María
Valparaíso, Chile
Mass 2013, Odense
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 1 / 22
LHC at Odense
For sure, people at Odense need more LHC data !
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 2 / 22
Contents
1 Simple ModelBasic IdeaReview of the ModelLimits based on dijet spectrumh→ γγHiggs-strahlung
2 A Not So Simple Model
3 Comments and Conclusions
4 Further Thought a Little Bit Out of Subject (If time allows)
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 3 / 22
Simple Model Basic Idea
Original Motivation
In 2005 I read about the fantastic idea of a light composite Higgs inWTC:
D. D. Dietrich, F. Sannino and K. Tuominen, �Light composite Higgsfrom higher representations versus electroweak precisionmeasurements: Predictions for LHC,� Phys. Rev. D 72, 055001 (2005)[arXiv:hep-ph/0505059].
A question arose: Is there a clear collider signal ?
Idea: Associate Higgs and Gauge boson production should beenhanced because of the presence of vector resonances
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 4 / 22
Simple Model Basic Idea
Basic Idea
Suppose that:
A new strong sector is responsible for EWSB
The new strong sector produces
A light scalar (Higgs)Vector resonances (Techni-rho and Techni-omega)
Can we construct a simple model which can help us to understand thebasic phenomenology ?
Warning
The spectrum considered here is not the low energy spectrum suggested byMWT !
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 5 / 22
Simple Model Basic Idea
Basic Idea
Suppose that:
A new strong sector is responsible for EWSB
The new strong sector produces
A light scalar (Higgs)Vector resonances (Techni-rho and Techni-omega)
Can we construct a simple model which can help us to understand thebasic phenomenology ?
Warning
The spectrum considered here is not the low energy spectrum suggested byMWT !
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 5 / 22
Simple Model Review of the Model
Basic Lagrangian
Gauge Sector: old VMD idea
L = −1
2Tr {WµνW
µν} − 1
2Tr {ρµν ρµν} −
1
4BµνB
µν − 1
4ωµν ω
µν
+M2Tr
{(g
g2Wµ − ρµ
)2}
+M2
2
(g ′
g2Bµ − ωµ
)2
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 6 / 22
Simple Model Review of the Model
Basic Lagrangian
Gauge Sector: old VMD idea
L = −1
2Tr {WµνW
µν} − 1
2Tr {ρµν ρµν} −
1
4BµνB
µν − 1
4ωµν ω
µν
+M2Tr
{(g
g2Wµ − ρµ
)2}
+M2
2
(g ′
g2Bµ − ωµ
)2
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 6 / 22
Simple Model Review of the Model
Basic Lagrangian
Fermion Sector
L = ψLiγµDµψL + ψR iγ
µDµψR ,
with
Dµ = ∂µ + iτ ag(1− x1)W aµ + iτ ag2x1ρ
aµ
+iY
2g ′(1− x2)Bµ + i
Y
2g ′2x2ωµ
and
Dµ = ∂µ + iY
2g ′(1− x3)Bµ + i
Y
2g ′2x3ωµ.
xi = 2(g/g2)2 for i = 1, 2, 3 in order to be consistent with precisionmeasurements (see BESS model)
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 7 / 22
Simple Model Review of the Model
Basic Lagrangian
(A very standard) Higgs Sector
L = (DµΦ)† (DµΦ) + µ2Φ†Φ− λ(
Φ†Φ)2
Dµ = ∂µ + iτ ag(1− f1)W aµ + iτ ag2f1ρ
aµ
+iY
2g ′(1− f2)Bµ + i
Y
2g ′2f2ωµ.
For simplicity f1 = f2 = 0
Higgs boson localized at �1�sites
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 8 / 22
Simple Model Review of the Model
Mass Matrix for the spin-1 sector
Mneutral =v2
4
(1 + α2)g2 −α2gg2 −gg ′ 0−α2gg2 α2g22 0 0−gg ′ 0 (1 + α2)g ′2 −α2g ′g20 0 −α2g ′g2 α2g ′2
Mcharged =
v2
4
[(1 + α2)g2 −α2gg2−α2gg2 α2g22
]
M = αvg22
We chose α = 4π
Λ = αv is the scale at whichvector resonances get mass
It is natural to take Λ = 4πv
After choosing the value of α we have only one free parameter: M
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 9 / 22
Simple Model Review of the Model
Mass Eigenstates (g/g2, g′/g2 << 1 limits)
A =g ′√
g2 + g ′2W 3 +
g√g2 + g ′2
B
+gg ′
g2√g2 + g ′2
ρ3 +gg ′
g2√g2 + g ′2
ω
Z =g√
g2 + g ′2W 3 − g ′√
g2 + g ′2B
+g2
g2√g2 + g ′2
ρ3 − g ′2
g2√g2 + g ′2
ω
W± = W± +g
g2ρ±
ρ0 = − g
g2W 3 + ρ3
ω = −g′
g2B + ω
ρ± = ρ± − g
g2W±
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 10 / 22
Simple Model Review of the Model
Results from 2006: enhancement in Higgs-strahlung channel
AZ,Eur. Phys. J. C 46 (2006) 791u,d
u,d
ZH
Z
u,d
u,d
ρ0H
Z
u,d
u,d
ω0H
Z
u
d
W+ H
W+
u
d
ρ+ H
W+
Mρ (GeV)
σ−σsm
σsm
500450400350300250200
1.4
1.2
1
0.8
0.6
0.4
0.2
0
Figure: pp− >W+h√s = 14 TeV
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 11 / 22
Simple Model Review of the Model
Update
Is the prediction of an enhancement in the Higgs-strahlung channelstill valid today ?
We decided to update our results
Oscar Castillo-Felisola, Cristóbal Corral, Marcela González,Gastón Moreno, Nicolás A. Neill, Felipe Rojas,
Jilberto Zamora and AZarXiv:1308.1825
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 12 / 22
Simple Model Limits based on dijet spectrum
Invariant Mass Dijet Spectrum and Limits on M
We implemented themodel in CalcHEP
We generated events forpp− > jj at
√s = 8 TeV
We extracted theresonant cross sectionand applied theappropriate cuts.
We compared withATLAS limits (
√s = 8,∫
Ldt = 13.0 fb−1)
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 13 / 22
Simple Model Limits based on dijet spectrum
Invariant Mass Dijet Spectrum and Limits on M
We implemented themodel in CalcHEP
We generated events forpp− > jj at
√s = 8 TeV
We extracted theresonant cross sectionand applied theappropriate cuts.
We compared withATLAS limits (
√s = 8,∫
Ldt = 13.0 fb−1)
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 13 / 22
Simple Model Limits based on dijet spectrum
Invariant Mass Dijet Spectrum and Limits on M
We implemented themodel in CalcHEP
We generated events forpp− > jj at
√s = 8 TeV
We extracted theresonant cross sectionand applied theappropriate cuts.
We compared withATLAS limits (
√s = 8,∫
Ldt = 13.0 fb−1)
Mjj(GeV)
Nu
mb
er
of
Ev
en
ts (
arb
itra
ry u
nit
s)
0
250
500
750
1000
1250
1500
1750
2000
1000 1500 2000 2500 3000 3500
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 13 / 22
Simple Model Limits based on dijet spectrum
Invariant Mass Dijet Spectrum and Limits on M
We implemented themodel in CalcHEP
We generated events forpp− > jj at
√s = 8 TeV
We extracted theresonant cross sectionand applied theappropriate cuts.
We compared withATLAS limits (
√s = 8,∫
Ldt = 13.0 fb−1)
Mjj(GeV)
Nu
mb
er
of
Ev
en
ts (
arb
itra
ry u
nit
s)
0
50
100
150
200
250
300
350
400
450
2500 2600 2700 2800 2900 3000 3100 3200 3300 3400 3500
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 13 / 22
Simple Model Limits based on dijet spectrum
Invariant Mass Dijet Spectrum and Limits on M
We implemented themodel in CalcHEP
We generated events forpp− > jj at
√s = 8 TeV
We extracted theresonant cross sectionand applied theappropriate cuts.
We compared withATLAS limits (
√s = 8,∫
Ldt = 13.0 fb−1)
σ × Acceptance (pb)
10−3
0,01
0,1
M (GeV)
1800 2000 2200 2400 2600 2800 3000
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 13 / 22
Simple Model h → γγ
h→ γγ
We compute
Rγ =Γ(h→ γγ)Model
Γ(h→ γγ)SM
It receives extra contributionfrom the ρµ running intoloops. The contribution isformally equal to the Wµ
contribution except that issuppressed by a W -ρ mixingfactor.
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 14 / 22
Simple Model h → γγ
h→ γγ
We compute
Rγ =Γ(h→ γγ)Model
Γ(h→ γγ)SM
It receives extra contributionfrom the ρµ running intoloops. The contribution isformally equal to the Wµ
contribution except that issuppressed by a W -ρ mixingfactor.
Rγ
1.2
1.3
1.4
1.5
1.6
1.7
1.8
M (GeV)
2200 2400 2600 2800 3000
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 14 / 22
Simple Model Higgs-strahlung
Higgs-strahlung
Z h
W⁺ hσModel/σSM
0
0.02
0.04
0.06
0.08
0.1
M (GeV)
2200 2400 2600 2800 3000
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 15 / 22
A Not So Simple Model
More complicated models are Possible
Claudio Dib, Antonio Cárcamo, AZ, ArXiv:1304.0286
Gauge Structure
SU(2)L × SU(2)R︸ ︷︷ ︸ × SU(2)C × SU(2)D︸ ︷︷ ︸⊃ HLS
[SU(2)L × U(1)Y ]Local
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 16 / 22
A Not So Simple Model
More complicated models are Possible
BSM Spectrum
1 Vector (Vµ)
1 Axial-Vector (Aµ)
1 light scalar: �Higgs� (h)
1 heavy scalar (H)
1 heavy pseudo scalar (η)
Comment
This is a more MWT-inspired spectrum
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 17 / 22
A Not So Simple Model
More complicated models are Possible
BSM Spectrum
1 Vector (Vµ)
1 Axial-Vector (Aµ)
1 light scalar: �Higgs� (h)
1 heavy scalar (H)
1 heavy pseudo scalar (η)
Comment
This is a more MWT-inspired spectrum
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 17 / 22
A Not So Simple Model
More complicated models are Possible
Some Characteristics of the model
Additional non-standard W -B mixing
it helps to the consistency with precision parameters S , T and U forappropriate values of κ = MV /MA
Hierarchy between the mass of the light scalar and the mass of theheavy ones is produced by loop corrections (not put by hand)
nice concordance with ATLAS for h→ γγ
Again h is weakly coupled to V and A (result of the model)
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 18 / 22
A Not So Simple Model
More complicated models are Possible
h→ γγ
0.60 0.65 0.70 0.75 0.80 0.85 0.90 0.95
0.0
0.5
1.0
1.5
2.0
Κ
RΓΓ
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 19 / 22
Comments and Conclusions
Comments and Conclusions
A few years ago we wanted to predict big impressive New Physicssignals
Now we are trying to hide our New Physics
The Simple Model is surprisingly consistent with LHC measurements
Reasons:
The Higgs is weakly coupled to the resonances (form factors ?)We have chosen Λ ≈ 3 TeV
More complicated things can be done but the big picture is there
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 20 / 22
Further thoughts
Further thoughts
During medieval times, the educated European circles acceptedwithout problem a spherical earth.Indeed, they had a model based on symmetry
Questions
Are antipodeans possible ? (I'm one)
Monsters ?
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 21 / 22
Further thoughts
Further thoughts
During medieval times, the educated European circles acceptedwithout problem a spherical earth.Indeed, they had a model based on symmetry
Questions
Are antipodeans possible ? (I'm one)
Monsters ?
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 21 / 22
Further thoughts
Further thoughts
During medieval times, the educated European circles acceptedwithout problem a spherical earth.Indeed, they had a model based on symmetry
Questions
Are antipodeans possible ? (I'm one)
Monsters ?
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 21 / 22
Further thoughts
When the European explorers crossed the Equator they didn't �ndmonsters
A better understanding of gravity explained the lack of anomaly
We are also crossing a barrier (the TeV barrier) and it seems there isnot monsters
LEP already gave an alert about the absence of monsters
Maybe a new better understanding (gravity again ?) may solve theparadox
or maybe we should look at the world upside down:
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 22 / 22
Further thoughts
When the European explorers crossed the Equator they didn't �ndmonsters
A better understanding of gravity explained the lack of anomaly
We are also crossing a barrier (the TeV barrier) and it seems there isnot monsters
LEP already gave an alert about the absence of monsters
Maybe a new better understanding (gravity again ?) may solve theparadox
or maybe we should look at the world upside down:
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 22 / 22
Further thoughts
When the European explorers crossed the Equator they didn't �ndmonsters
A better understanding of gravity explained the lack of anomaly
We are also crossing a barrier (the TeV barrier) and it seems there isnot monsters
LEP already gave an alert about the absence of monsters
Maybe a new better understanding (gravity again ?) may solve theparadox
or maybe we should look at the world upside down:
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 22 / 22
Further thoughts
When the European explorers crossed the Equator they didn't �ndmonsters
A better understanding of gravity explained the lack of anomaly
We are also crossing a barrier (the TeV barrier) and it seems there isnot monsters
LEP already gave an alert about the absence of monsters
Maybe a new better understanding (gravity again ?) may solve theparadox
or maybe we should look at the world upside down:
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 22 / 22
Further thoughts
When the European explorers crossed the Equator they didn't �ndmonsters
A better understanding of gravity explained the lack of anomaly
We are also crossing a barrier (the TeV barrier) and it seems there isnot monsters
LEP already gave an alert about the absence of monsters
Maybe a new better understanding (gravity again ?) may solve theparadox
or maybe we should look at the world upside down:
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 22 / 22
Further thoughts
When the European explorers crossed the Equator they didn't �ndmonsters
A better understanding of gravity explained the lack of anomaly
We are also crossing a barrier (the TeV barrier) and it seems there isnot monsters
LEP already gave an alert about the absence of monsters
Maybe a new better understanding (gravity again ?) may solve theparadox
or maybe we should look at the world upside down:
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 22 / 22
Further thoughts
When the European explorers crossed the Equator they didn't �ndmonsters
A better understanding of gravity explained the lack of anomaly
We are also crossing a barrier (the TeV barrier) and it seems there isnot monsters
LEP already gave an alert about the absence of monsters
Maybe a new better understanding (gravity again ?) may solve theparadox
or maybe we should look at the world upside down:
Alfonso R. Zerwekh (UTFSM) Higgs and Vector Resonances Mass 2013, Odense 22 / 22