Technicolor in the LHC Era R. Sekhar Chivukula Michigan State - PowerPoint PPT Presentation

Technicolor in the LHC Era R. Sekhar Chivukula Michigan State University

ATLAS Higgs Results Lepton-Photon 2011

CMS Higgs Results Lepton-Photon 2011

These headlines are missing the point... ATLAS/CMS are exploring a whole new world!

LHC Higgs Sensitivity σ ( pp → H ) λ t BR ( H → X ) W + , Z f H H ¯ f λ V V λ f W − , Z Reach Extends to non-standard models including models of DEWSB!

Dynamical Electroweak Symmetry BReaking

Technicolor • Use scaled-up QCD to break electroweak symmetry No hierarchy problem! S? Gauge Symmetry + SSB = Higgs Mechanism But: difficult to accommodate top-quark!

Walking Technicolor If β TC ∼ 0, we expect γ m ∼ 1, enhancing fermion masses. A realistic (E)TC model will not be like QCD! Holdom, Yamawaki et. al., Appelquist and Wijewardana

Low/Multi-Scale technicolor Or, minimal SU(2) theory... Sannino, et. al. Eliminated by Lattice Calculations! Our interest: π 0TC e.g.The “Technicolor” Straw Man Lane and Mrenna, Phys. Rev. D67:115011,2003 Eichten, Lane, Womersley

Top Quark Mass Generation Challenge : ETC must violate custodial symmetry to make m t >> m b . But how to keep this from causing additional large contributions to ? ∆ ρ Are new interactions required to explain top-quark mass?

TopColor Assisted Technicolor 1 v 2 = = f 2 t + F 2 T C ⇡ (246 GeV) 2 , f t = O (60 GeV) ⌧ v p 2 G F Hill, hep-ph/9411426

Technicolor in the LHC Era RSC, EHS, P. Ittisamai, J. Ren, arxiv:1110.3688

LHC Technipion Sensitivity ∝ ε t m t ∝ m b F P F P b g g Q t P P Q t P Q ¯ t b g g g 1 g 2 ✏ µ νλσ k µ 1 k ν 2 ✏ λ 1 ✏ σ A ( P → V 1 V 2 ) = N T C A V 1 V 2 2 8 ⇡ 2 F P Models with Colored Technifermions TC models PNGB and content v/F P A gg A �� λ l λ f 3 (3¯ L γ 5 L − ¯ 1 − 1 4 P 1 FS one family (Farhi:1980) Q γ 5 Q ) 2 1 1 √ √ √ 4 3 3 3 q √ 6 (3 ¯ E γ 5 E − ¯ 1 − 1 16 2 P 0 Variant one family (Casalbuoni:1998) D γ 5 D ) 1 6 √ √ √ 3 2 6 3 6 2 (¯ L ` γ 5 L ` − 2 ¯ √ √ 1 − 2 2 8 2 P 0 LR multiscale (Lane:1991) Q γ 5 Q ) 4 1 1 √ 3 9 6 √ N D 3 (3¯ L γ 5 L − ¯ π 0 0 1 − 1 100 TCSM low scale (Lane:1999) Q γ 5 Q ) 1 1 T √ √ √ 4 3 27 3 √ 2 (3¯ L γ 5 L − ¯ 1 − 1 P 1 2 y 2 MR Isotriplet (Manohar:1990) Q γ 5 Q ) 4 24 1 1 √ √ 6 2

Technipion Properties 130 GeV One Variant Multiscale TCSM Isotriplet Decay Family one family low-scale SM Channel N T C N T C N T C N T C N T C N T C N T C N T C N T C N T C Higgs =2 =4 =2 =4 =2 =4 =2 =4 =2 =4 b ¯ 77 56 61 50 64 36 77 56 60 31 49 b c ¯ c 7 5.1 0 0 5.8 3.2 7 5.1 5.4 2.8 2.3 τ + τ − 4.5 3.3 32 26 3.8 2.1 4.5 3.3 3.5 1.8 5.5 gg 12 35 7 23 26 59 12 35 14 29 7.9 0.011 0.033 0.11 0.35 0.025 0.056 0.088 0.26 17 36 0.23 γγ W + W − 0 0 0 0 0 0 0 0 0 0 31 350 GeV One Variant Multiscale TCSM Isotriplet Decay Family one family low-scale SM Channel N T C N T C N T C N T C N T C N T C N T C N T C N T C N T C Higgs =2 =4 =2 =4 =2 =4 =2 =4 =2 =4 b ¯ b 44 18 42 20 24 7.7 44 18 20 6.2 0.036 c ¯ c 4 1.6 0 0 2.2 0.69 4 1.6 1.8 0.56 0.0017 τ + τ − 2.6 1 22 11 1.4 0.45 2.6 1 1.2 0.36 0.0048 gg 49 79 35 68 72 91 49 79 34 41 0.085 0.047 0.076 0.54 1 0.069 0.087 0.36 0.58 42 51 ∼ 0 γγ W + W − 0 0 0 0 0 0 0 0 0 0 68

Light Technipion Limits: γγ 10 2 10 6 γγ channel γγ channel Variant One Family (Casalbuoni et al) Isotriplet (Manohar-Randall) CMS (1.66 fb -1 )+ATLAS (1.08 fb -1 ) 10 5 N TC =4 N TC =3 ( σ x BR) P / ( σ x BR) SM ( σ x BR) P / ( σ x BR) SM N TC =2 10 1 10 4 10 3 CMS (1.66 fb -1 )+ATLAS (1.08 fb -1 ) N TC =4 N TC =3 10 0 10 2 N TC =2 10 1 10 -1 10 0 110 115 120 125 130 135 140 145 110 115 120 125 130 135 140 145 M P [GeV] M P [GeV]

Light Technipion Limits: ττ 10 2 10 3 ττ channel ττ channel Variant One Family (Casalbuoni et al) Isotriplet (Manohar-Randall) CMS (1.6 fb -1 )+ATLAS (1.06 fb -1 ) CMS (1.6 fb -1 )+ATLAS (1.06 fb -1 ) N TC =4 N TC =4 N TC =3 N TC =3 ( σ x BR) P / ( σ x BR) SM ( σ x BR) P / ( σ x BR) SM N TC =2 N TC =2 10 2 10 1 10 1 10 0 10 0 110 115 120 125 130 135 140 145 110 115 120 125 130 135 140 145 M P [GeV] M P [GeV]

Heavy Technipion Limits: ττ 10 3 10 3 ττ channel ττ channel One Family (Farhi-Susskind) Multiscale (Lane-Ramana) ε t =0.5 ε t =0.5 ATLAS (1.06 fb -1 ) ATLAS (1.06 fb -1 ) 10 2 10 2 N TC =4 N TC =6 N TC =3 N TC =4 σ gg x BR( ττ ) [pb] σ gg x BR( ττ ) [pb] N TC =2 N TC =3 10 1 Top-loop (N TC =2) N TC =2 Top-loop (N TC =2) 10 1 10 0 10 0 10 -1 10 -2 10 -1 150 200 250 300 350 150 200 250 300 350 M P [GeV] M P [GeV] g g t Q P P +/- t Q ε t m t Q t g g F P

Conclusions: Part I • ATLAS/CMS results are strongly constraining technipions in models with colored technifermions. • We are (finally!) at the TeV frontier.

Conclusions: Part I

Higgsless Models

General Principles Higgsless models are low-energy effective theories of Dynamical Electroweak Symmetry Breaking with. They include: • massive 4-d gauge bosons arise in the context of a 5-d gauge theory with appropriate boundary conditions • WW scattering is unitarized through exchange of KK modes (instead of scalar bosons) • the language of Deconstruction allows a 4-d “Moose” representation of the model Csaki, Grojean, Murayama, Pilo, Terning hep-ph/0305237 ; Chivukula & He hep-ph/0201164

p R 1 3-Site Model: Basic Structure SU (2) × SU (2) × U (1) g 0 , g 2 � g 1 ψ R 1 t R 2 , b R 2 R f 1 f 2 g 0 g 1 g 2 L ψ L 0 ψ L 1 Gauge boson spectrum : photon, Z, Z’, W, W’ (as in BESS) ψ Fermion spectrum: t, T, b, B ( is an SU(2) doublet) and also c,C, s,S, u,U, d,D plus the leptons RSC, Coleppa, DiChiara, He, Kurachi, EHS, Tanabashi hep-ph/0607124

3-Site Fermion masses SU (2) × SU (2) × U (1) R g 0 , g 2 � g 1 f 1 f 2 g 0 g 1 g 2 L LH Boundary Fermion “Bulk Fermion” RH Boundary Fermion  ✓ ◆ ✓ ◆� ✏ uR u R 2 0 ✏ L ¯ L 0 Σ 01 R 1 + ¯ R 1 L 1 + ¯ M L 1 Σ 12 ✏ dR d R 2 0 degree of delocalization ordinary fermion masses are of the form m f ≈ M ✏ L ✏ fR each ordinary fermion mass value is tied to ✏ fR flavor structure same as in standard model heavy “KK” fermion masses are ~ M

3-Site Ideal Delocalization i ) 2 = g W v w g i ( ψ f General ideal delocalization condition i g 0 ( ψ f L 0 ) 2 L 1 ) 2 = v 0 is realized as in 3-site model W g 1 ( ψ f v 1 W From the W, fermion eigenvectors, one solves for ⇤ � ⇥ ⌅ � 2 x 2 ⇥ 2 ⇥ 2 1 � g 0 � M W x 4 + · · · fR � 2 L → (1 + � 2 fR ) 2 x 2 ≡ 2 + ≈ 4 8 − M � 2 g 1 W ✓ M 2 ◆ ✏ 2 W For all but top quark, � fR � 1 so the choice L ≈ 2 M 2 W 0 makes W’ fermiophobic and Z’ nearly so S = ˆ ˆ T = W = 0 Y = M 2 W ( Σ W − Σ Z ) Use WW scattering to see W’: Birkedal, Matchev, Perelstein hep-ph/0412278

3-Site Parameter Space Chivukula et al. hep-ph/0607124 KK fermion mass (GeV) M T,B 25000 Allowed Region 20000 Unitarity M W 0 << M T,B violated 15000 10000 ∆ ⇢ = M 2 ✏ 4 tR 5000 16 ⇡ 2 v 2 0 M W’ 400 600 800 1000 1200 W’ mass (GeV) WWZ vertex 1-loop fermionic EW visibly altered precision corrections too large

LHC Phenomenology RSC, EHS, H.-J. He, Y.-P. Kuang, et. al. arxiv: 0708.2588

LHC Signatures: W’,Z’ Production and Decay at LHC νν References

W’ production at LHC Two processes with large rates and clear signatures! Vector Boson LHC @14 TeV Fusion Associated Production

Associated Production (WZZ channel) 500 GeV W’ boson References

Vector Boson Fusion (WZjj channel) 500 GeV W’ boson Background is 10x larger than estimated in Birkedal, Matchev & Perelstein (2005) forward jet tag removes WZ background

Integrated Luminosity for W’ Discovery Associated LHC at 14 TeV Fusion

Conclusions: Part II • ATLAS/CMS will have substantial reach in Higgsless models as well, at 14 TeV. • Investigations at 7 TeV are underway.

Backup Slides

Z’ Search at LHC Ohl & Speckner predict that the 3- site Z’ boson (at or near ideal delocalization) should be visible in 100 fb -1 of LHC data p T ≥ 50 GeV | cos θ | ≤ 0 . 95 75 GeV ≤ m jj ≤ 85 GeV M W 0 = 500 GeV Ohl & Speckner arXiv:0809.0023