Strong Top Dynamics in Light of LHC Data

Home , Topcolor, Top quark condensate

Elizabeth H. Simmons Michigan State University

- EWSB and Strong Top Quark Dynamics - Models - States Connected to the New Dynamics - LHC Prospects - Conclusions

JLAB 4 April 2012 Looking Beyond the Standard Model

technicolor

topcolor susy

extra dim.

Fundamental scalars observed? Hierarchy/Naturalness?

Triviality? Dynamics causing EWSB? EWSB and Strong Top Quark Dynamics Dynamical EWSB:

Technicolor: (inspired by QCD)

Introduce SU(N)TC with technigluons, inspired by QCD gluons

techniquarks carrying SU(N)TC charge:

• e.g. weak doublet TL = (UL, DL); weak singlet UR, DR • Lagrangian has SU(2)L x SU(2)R chiral symmetry

SU(N)TC gauge coupling becomes large at 1TeV TC • ! T L T R "≈ 250 GeV causes EWSB

• `technipions’ Π TC become the WL, Z L Susskind, Weinberg Dynamical Fermion Masses: ETC*

METC > TC

ETC boson technigluon

E.g. the top quark mass arises from:

gETC 2 and its size is ( ) !TT¯ " x (ﬂavor-dependent factor) METC

Challenge: ETC must violate custodial symmetry to make mt >> mb. But how to avoid large changes to ? *Dimpoulos & Susskind; Eichten & Lane Isospin Violation (I)

mt = 172 GeV

References Isospin Violation (2)

Conclusion: t,b feel a Text new strong force not shared by other quarks References or technifermions Top Condensation and EWSB

If the top quark feels a new strong interaction, a top-quark condensate can provide some or even all of electroweak symmetry breaking v2 = f 2 + f 2 sin ! f /v TC t ⌘ t some (topcolor*, topcolor-assisted technicolor*) in these models the top quark feels an additional gauge interaction that causes top condensation

all (top mode^, top seesaw^^) in top seesaw models, a heavy partner quark T forms the condensate; the top quark mass eigenstate that we observe is a seesaw mixture between T and the standard model’s top quark gauge eigenstate

* Hill ^Bardeen,Hill &Lindner; Yamawaki; Miranski; Nambu ^^Chivukula, Dobrescu, Georgi & Hill Physical Realization: Topcolor

One physical realization of a new interaction for top is a (spontaneously broken) extended color gauge group: topcolor M SU(3)h SU(3)` SU(3) ⇥ ! QCD where (t,b) feel SU(3)h and (u,c,d,s) feel SU(3)l

Below the scale M, exchange of massive topgluons 4⇡ a 2 t¯ t yields four-fermion interactions among top quarks M 2 µ 2 ✓ ◆

Note: M >> 1TeV implies ﬁne tuning Models

Hill hep-ph/9411426 Dobrescu & Hill hep-ph/9712319

Chivukula, Christensen, Coleppa, Simmons arXiv:0906.5667 Chivukula, Coleppa, Logan, Martin, Simmons arXiv:1101.6023 Topcolor-Assisted Technicolor (TC2)

technicolor: provides most of EWSB topcolor: provides most of mt hypercharge: keeps mb small C.T. Hill Pure Top Condensation?

The relationship between v, M, and mt when strong topcolor dynamics causes top condensation and EWSB

Pagels-Stokar formula (1979) in NJL approximation

175 Top Seesaw

175

Dobrescu & Hill hep-ph/9712319; Chivukula et al. 9809470; Collins, Grant, Georgi 9908330; He, Hill, Tait 0108041 Effective Theory: “Top Triangle Moose”

Gauge structure: ψL0 f-constants of SU(2) × SU(2) × U(1) 0 ⌃01, ⌃12 are g0,g2 ! g1 g vp2 cos 01 Top-Higgs = v sin ! ~ ψL1 h i g 1 ψR1 Gauge boson spectrum: photon, Z, Z’, W, W’ g’ 12 (as in 3-site, BESS or HLS) 2 Fermion spectrum: t, T, b, B; similar for light tR2,bR2 quarks & leptons only top couples to Triangle Moose and Topcolor-Assisted TC

ψL0

~ ψL1 Topcolor g 1 (E)TC sector ψR1 sector

g’ 12 { 2 } tR2,bR2

This effective theory can interpolate between the TC2 and top seesaw models New States Connected to Top Dynamics topgluon / coloron: Ca • can be ﬂavor (non)universal fractional shift in ✏tL to help Rb agree with data top-Higgs state: Ht 0.7 • production in gg → Ht higher 1 than in SM by factor[sin !] 0.6 0 top-Pion states: ⇧t±, ⇧t 0.5 w one-loop Rb contributions 0 • sin 0 minimized by (tree) non-ideal 0.4 delocalization of tL as indicated in

plot at right: 0.3 0.20.2 0.6 0.4 top’s seesaw partner: T 0.8 0.4 sin ! 0.2 1 0.6 200 400 600 800 1000 can be produced at LHC M GeV • Pt M⇧t H L LHC vs. Colorons

ATLAS: CERN-PH-EP-2011-127 CMS: CERN-PH-EP/2011-119

Braam, Chivukula, DiChiara, Flossdorf, Simmons arXiv:0711.1127 Han, Lewis, Liu arXiv:1010.4309 Chivukula, Farzinnia, Foadi, Simmons arXiv:1111.7261 Limits on Topgluons / Colorons 7

conducted on random samples of events generated from our smooth background parameter- Flavor-universal colorons:ization. The use of wide jets instead of AK7 jets improves the expected upper limits on the resonance cross section by roughly 20% for gg, 10% for qg, and 5%4 for qq resonances. • LHC searches for colorons in dijet constrain MC > 2.5 TeV

String Resonance q* s8 Excited Quark

3 (pb) [pb] [pb] 3 Axigluon/Coloron 10 A 10 E Diquark A 1 Observed 95% CL upper limit6 Observed 95% CL upper limit W’ × × ×

Expected 95% CL upper limit Expected 95% CL upper limit Z’ σ σ 2 RS Graviton 2 B 10 68% and 95% bands 10 68% and 95% bands × 10 10 -1 ATLAS 10 ATLAS -1 -1 L dt = 1.0 fb -1 L dt = 1.0 fb 1 ∫ CMS (1.0 fb ) ∫ s = 7 TeV 1 s = 7 TeV s = 7 TeV 10-1 |η| < 2.5, |Δη| < 1.3

-1 Cross Section 95% CL Upper Limit 10 10-2 Gluon-Gluon -2 10 Quark-Gluon Quark-Quark 10-2 1000 2000 3000 4000 10001000 2000 1500 2000 3000 2500 3000 4000 3500 4000 Mass [GeV] ResonanceMass [GeV] Mass (GeV) (a)Excited-quark and axigluon models. Figure 5: The 95% CL upper(b)Colour limits octet on scalars model.B A for dijet resonances of type gluon-gluon (open ⇥ ⇥ circles), quark-gluon (solid circles), and quark-quark (open boxes), compared to theoretical pre- FIG.Topgluons 2. The 95% CL upper coupled limits on σ preferentiallyas a functiondictions of particle for string massto resonances (black3rd filled generation: [3], circles). E6 diquarks The black [5], dotted excited curve quarks shows [6], axigluons [8], colorons [9], the 95% CL upper limit expected from× MonteA Carlo and the light and dark yellow shaded bands represent the 68% and 95% new gauge bosons W0 and Z0 [10], and Randall-Sundrum gravitons [11]. contoursFCNC of the expected bounds limit, respectively. from Theoretical B-mesonpredictions mixing: for σ are M shownC > in (a)6 forTeV excited quarks (blue dashed) and• axigluons (green dot-dashed), and in (b) for colour octetscalarresonances(bluedashed).Foragivennewphysicsmo× A del, the observed (expected) limit occurs at the crossing of its σ curve with the observed (expected) 95% CL upper limit curve. Fits of TC2 to precision electroweak× A data: MC ~ 18 TeV • Table 2: For each model we list the observed and expected upper values of the excluded mass derived from MC simulations. A prior probabilityrange den- at 95%of model CL. The parameters, lower value of ofPDF the set, excluded and of mass MC tune. range Pre- from this search is 1 TeV. sity constant in all positive values of signal cross section, vious ATLAS studies have already explored the impact and zero at negative values, is used. The posterior prob- of different MC tunes and PDF sets on the q∗ theoretical ability is then integrated to determine the 95% CL for a prediction [4]. Model Excluded Mass (TeV) given range of models, usually parameterised by the mass In 2011, the instantaneous luminosityObserved has risenExpected to a of the resonance. level where correctionsString Resonances must be made for multiple4.00 pp col-3.90 Limits are determined on σ for a hypothetical new lisions occurring inE theDiquarks same bunch crossing3.52 (“pileup”),3.28 ×A 6 particle decaying into dijets. The acceptance includes all whose presence aExcitedffects the Quarks measurement2.49 of calorimeter2.68 reconstruction steps and analysis cuts described above, energy depositionsAxigluons/Colorons associated with the hard-scattering2.47 2.66 and assumes that the trigger is fully efficient. (The effi- event under study.W’ All Bosons simulated samples1.51 used in this1.40 ciency is greater than 99% for all analyses.) analysis include a Poisson distributed number of MC The effects of systematic uncertainties due to the minimum bias events added to the hard interaction to knowledge of the luminosity and of the jet energyIn scale Fig. 5 weaccount compare for the “in-time” observed pileup upper caused limits by to additional the model colli- predictions as a function of reso- (JES) are included. The luminosity uncertainty fornance the mass.sions The in predictions the same bunch are from crossing. lowest-order Further calculations account must [24] of the product s B A be taken of “out-of-time” pileup originating from colli- ⇥ ⇥ 2011 data is 3.7% [35]. The systematic uncertaintyusing on CTEQ6L1 parton distributions [19]. New particles are excluded at the 95% CL in mass re- sions in bunches preceding or following the one of inter- the JES is taken from the 2010 data [18] analysis,gions and for which the theory curve lies above our upper limit for the appropriate pair of partons. is adapted to the 2011 analysis taking into account in est, due to the long response time of the liquid argon We also determinecalorimeters. the expected With the lower 50 ns limit bunch on spacing the mass in of the each LHC new particle by comparing the particular the new event pileup conditions (describedexpected be- cross section limits to the model predictions. An example of the expected limits is low). The JES uncertainty shifts resonance peaks by less for these data, up to 12 preceding bunches and 1-2 follow- shown in Fig. 6 where for qg resonances we compare the expected limits and their uncertainty than 4%. The background parameterization uncertainty ing bunches contribute to out-of-time pileup. Although is taken from the fit results, as described in [6]. Thebands effect to boththe conditions observed limits modelled and in model MC arepredictions. realistic, Our they search may starts at a resonance mass of the jet energy resolution (JER) uncertainty is found to not perfectly match the data due to bunch train struc- be negligible. All of these uncertainties are incorporated ture and instantaneous luminosity variations in the LHC. into the fit by varying all sources according to Gaussian The MC events are therefore reweighted to remove these probability distributions and convolving them with the residual differences. Following this procedure the pileup Bayesian posterior probability distribution. Credibility description in MC is sufficiently good that no additional intervals are then calculated numerically from the result- uncertainty on the JES is required for jets with pT > 100 ing convolutions. No uncertainties are associated with GeV. the theoretical model of new physics, as in each case the The resulting limits are shown in Fig. 2. For excited model is a benchmark that incorporates a specific choice quarks, the acceptance ranges from 37 to 51% for mq∗ A Colorons at NLO

+ + + +

virtual corrections

real corrections + +

RSC, Farzinnia, Foadi, EHS arXiv:1111.7261 Impact of NLO Corrections

rLπrR rLπrR 3.2 100 3.0 NLO 10 2.8 L

H 1

pb 2.6 ◊

B 0.1

◊

s 2.4 0.01 LO 2.2 0.001 1.0 1.5 2.0 2.5 3.0 3.5 4.0 1.0 1.5 2.0 2.5 3.0 3.5 4.0

mF TeV MC TeV

H L H L

K-factor: / 30% • NLO LO ⇠ • 30% of produced colorons have pT > 200 GeV!

RSC, Farzinnia, Foadi, EHS arXiv:1111.7261 Impact of NLO Corrections

rLπrR rLπrR 3.2 100 3.0 NLO 10 2.8 L

H 1

pb 2.6 ◊

B 0.1

◊

s 2.4 0.01 LO 2.2 0.001 1.0 1.5 2.0 2.5 3.0 3.5 4.0 1.0 1.5 2.0 2.5 3.0 3.5 4.0

mF TeV MC TeV

scale dependenceH L at LO: 30% H L at NLO: 2%

K-factor: / 30% • NLO LO ⇠ • 30% of produced colorons have pT > 200 GeV!

RSC, Farzinnia, Foadi, EHS arXiv:1111.7261 Impact of NLO Corrections

rLπrR rLπrR 3.2 100 3.0 NLO 10 2.8 L

H 1

pb 2.6 ◊

B 0.1

◊

s 2.4 0.01 LO 2.2 0.001 1.0 1.5 2.0 2.5 3.0 3.5 4.0 1.0 1.5 2.0 2.5 3.0 3.5 4.0

mF TeV MC TeV

scale dependenceH L Axigluon mass at LO: 30% limit fromH CMSL Data at NLO: 2% rises to 2.6 TeV

K-factor: / 30% • NLO LO ⇠ • 30% of produced colorons have pT > 200 GeV!

RSC, Farzinnia, Foadi, EHS arXiv:1111.7261 LHC vs. Top Partner (T)

Chivukula, Christensen, Coleppa, Simmons arXiv:0906:5567 [hep-ph] Chivukula, Coleppa, Logan, Martin, Simmons arXiv:1101.6023 [hep-ph] KK Quark Production at LHC (triangle moose model)

Pair Production 10 10 gg"UU q Q s (pb) qq"UU 1 1 pp"UU _ g "

_ pb q ! Q Σ 0.10.1 g Q 0.010.01

g g _ 0.001 400 600 800 1000 1200 Q 400 600 800 1000 1200 MD GeV

MD (GeV) ! " 11.00 Single Production s (pb) 0.70 0.50.50 "

u,d U,D pb ! 0.3Σ 0.30 Z,Z’ 0.20.20 u,d u,d 0.15

400 600 800 1000 1200

400 600 MD 800GeV 1000 1200

MD !(GeV)" KK Quark Decay and Detection

KK fermion decay modes

U!W,d 0.60.6 MZ’ = 500 GeV U Wd U!Z,u BR 0.5 U!W’,d U!Z’,u 0.40.4 U Zu

BR 0.3

0.20.2 U W’d 0.1 U Z’u 0.00.0 400 600 800 1000 1200 400 600 800 1000 1200 MD GeV MD (GeV)

! "

QQ signature: pp QQ¯ WZqq ``` jj E/ ! ! ! T Qq signature: pp Qq W 0qq WZqq ``` jj E/T ! ! ! ! LHC Detection of KK Quarks

Integrated Pair Production Luminosity 1200 (fb-1) for 5 discovery of KK quarks 10001000 1 10 50 100 300 in LHC at 1 10 50 100 300 14 TeV "

GeV 800 !

800' W M

Heavy W’ 300 300 Mass (GeV) 600600 Single 100 Production 100 50 50 400400 400 600 800 1000 1200 400 600 800 1000 1200 MD GeV Heavy Quark Mass (GeV) ! " Top sector at LHC: T

Top’s KK partner, T, will be most visible in T →Wb. Analysis for other KK quark partners (assuming W→lν) still roughly applies; the channel with one hadronically-decaying W should offer larger signal and full reconstruction of T.

The T →Ht t decays will also be helpful.

TÆWb 0.8 TÆW' b TÆHt TÆPtt 0.6 TÆZt TÆPtb TÆZ' t BR 0.4

0.2

0.0 200 400 600 800 1000

MD GeV

H L Top sector at LHC

Sample strategy to ﬁnd states in the top sector and conﬁrm their connection to EWSB:

1. With initial LHC data, ﬁnd Ht in Ht → WW, ZZ; higher-than-SM production rate will indicate that it is exotic 2. As integrated luminosity grows, ﬁnd top quark’s KK partner T via its dominant decay to T → Wb

3. Conﬁrm the T → Ht t decay; this shows Ht is strongly coupled to the top sector as well as the EW sector

4. Discover Πt in pp → t Πt± ; this establishes the top-pion’s strong link to the top sector

5. Conﬁrm Πt in pp → Ht Πt±; this links the top-pion to the EW sector as well LHC vs. Top-Higgs

Chivukula, Coleppa, Logan, Martin, Simmons arXiv:1108.4000 [hep-ph]

Chivukula, Coleppa, Ittisamai, Logan, Martin, Ren, Simmons [in preparation] Top sector at FNAL: Ht

A top-Higgs of moderate mass would be visible in WW/ZZ -1 due to enhancement of gg → Ht production by [sinω] . E.g., see enhanced production relative to Tevatron* limit:

4 Tevatron upper limit sin ω = 0.2 3.5 0.3 0.4 3 0.5 0.6

WW) (pb) 0.7 2.5

→ SM

t 2 ) * BR(H

t 1.5 H

→ 1 (gg σ 0.5

0 120 140 160 180 200 220 240 260 280 300 M (GeV) Ht

*T. Aaltonen et al. [CDF and D0 Collaborations], arXiv:1005.3216 LHC limits on Higgs Production

Combined observed SM 102 ATLAS + CMS Preliminary, s = 7 TeV σ -1 Combined expected / Lint = 1.0-2.3 fb /experiment H bb

σ → H → ττ H → γγ H → WW H → ZZ 10

sinω < 0.7

sinω > 0.7 1 Asymptotic 95% CL limit on Asymptotic 95% CL 100 200 300 400 500 600 Higgs boson mass (GeV/c2) Non-standard Ht are Figure 14: The 95% C.L. upper limits for each Higgs boson decay mode separately, and tightly constrained CMS PAS HIG-11-011 combined, on the signal strength modiﬁer µ = /SM, obtained with the CLs method in the asymptotic approximation, as a function of the SM Higgs boson mass in the range 110-600 GeV/c2. The observed limits are shown by solid symbols. The dashed lines indicate the median expected µ95% value for the background-only hypothesis.

42 ATLAS vs Ht (if top-pion is light)

4 M = 172 GeV t 3.5 limit from ATLAS sin = 0.3 0.4 3 0.5 0.6 SM 2.5 0.7 0.8 * BR)

1.5 * BR/(

sin w = 0.5 1

0.5

0 200 250 300 350 400 450 500 550 600 M (GeV) Ht ATLAS vs Ht (if top-pion is heavier)

4 M = 172 GeV t 3.5 limit from ATLAS sin = 0.3 0.4 3 0.5 0.6 SM 2.5 0.7 0.8

* BR) M⇧t =400GeV

2 sin ! =0.5 1.5 * BR/( 1

0.5

0 200 250 300 350 400 450 500 550 600 M (GeV) Ht Bounds on Top-Pion Mass

Tevatron bounds on top decays to charged Higgs + bosons imply that BR ( t ⇧ t b ) 0 . 2 and exclude the dark-blue region below:! 

170

160 top-pion BR =0.05

mass 150

(GeV) BR =0.1 140 BR =0.2 M⇧t (GeV)130

120

110

100 0.3 0.4 0.5 0.6 0.7 f 0.8 sin ! LHC Limits on Top-Higgs (Ht )

0.8

0.7

0.6

0.5 allowed sin

0.4 (heavier top-pion) minimum M M = 130 GeVt t 0.3 150 GeV 172 GeV 400 GeV 0.2 200 250 300 350 400 450 500 550 M (GeV) Ht arXiv:1108.4000 arxiv:1108.4000 1.0 0.05

0.8 0.04 0 t 0.6 0 t

" 0.03 " BR of 0.4 BR of 0.02

0.2 0.01

0.0 0 0.00 New Limits From0.0 0.2⇧ t 0.4 0.6 0.8 1.0 0.0 0.2 0.4 0.6 0.8 1.0 ! SinΩ SinΩ As in RSC’s talk, LHC searches(a) for BR ofH two dominant channels (b) BR of other channels • SM ! set strict bounds on technipionsFigure 2: BR containing of all relevant channels as function of sin ω.Foreachchanneltwopionmassare shown, curve and dashed curve for 110GeV and 240GeV respectively. (a)showstwodominant colored technifermionschannels, blue lines for gg and red for bb.(b)forotherchannelofphysicsinterest,redforττ,green for WW,bluefor0 γγ,orangeforZZ. Those searches also constrain ⇧ t in the top • 0 triangle moose, mainly since ⇧ t production is with 2HDM[4],2 we draw it with respect to tan ω in its speciﬁc range. Even without displaying enhanced (relative to HSM) by cot !

10 2.0

m &110 GeV mP&110 GeV P mP&125 GeV mP&145 GeV 8 mP&145 GeV # # SM 1.5 SM ΓΓ ΓΓ

0 " "

This excludes ⇧ SM SM t 6 BR BR

0 Σ$ Σ$ 1.0

M < 150 GeV ! ! for ⇧t 4 if 0.2 sin ! 0.6 TTM TTM BR BR

Σ$ Σ$ 0.5   2

0 0.0 0.2 0.4 0.6 0.8 0.6 0.8 1.0 1.2 1.4 1.6 SinΩ TanΩ

(a) (b)

Figure 3: Enhancement factor for Π0 γγ by gluon fusion. The left panel is drawn with respect t → 0 0 to sin ω,formΠt =110, 145GeV respectively. In right panel, it is function of tan ω,formΠt = 110, 125, 145GeV respectively.

0 experimental data, it is already clear that light neutral top-pion in mass range 110GeV < mΠt < 150GeV has been excluded in natural parameter range of TC2, 0.2 ! sin ω ! 0.5.

2.5 Di-tau channel

0 For Πt produced by gluon fusion, search in ττ channel in light mass range is diﬃcult with large background from Drell-Yan process. It can be more eﬃcient by implementing cuts for VBF, which

7 unfortunately is absent for pseudoscalar. In higher mass range, however, gluon fusion production can be potentially interesting. As light mass range being excluded by di-photon channel, we inves- tigate bound on higher mass neutral top-pion up to 350GeV before top pair decay open. Exclusion 0 curve on σ BR m 0 plane for Π ττ in gluon fusion production is shown in Fig.(4), with · − Πt t → 0 ATLAS search without jet cuts[6]. The bound looks rather weak. In this small ω and large mΠt

ΤΤ channel

5 0.2 ' sinΩ 0.3 ' sinΩ

0.5 ' sinΩ

4 ATLAS limit $ pb

"# 3 Φ%ΤΤ !

Br 2 Σ#

0 160 180 200 220 240 260 280 300

M! !GeV"

0 Figure 4: Exclusion curve on σ BR m 0 plane for gg Π ττ.Theshadedregionisexcluded · − Πt → t → by ATLAS search. Diﬀerent color represents diﬀerent sin ω in TC2, Red for 0.2, Green for 0.3, Blue for 0.5.

0 range, gg is dominant among decay channels. And increasing in mΠt will suppress BR to ττ while leaving κprod nearly unchanged (slightly enhanced). New Limits From b s 3Chargedtop-pion ! Charged top-pions would contribute to b s like the charged Higgs state in a Type II 2HDM! ± As mentioned in (??), there is constraint from top decay if Π(t is lighter!) than top quark, that + with couplings+ going as + t Πt b.ProvidingthesamedecaymodeasH ,experimentalboundconstraints$ BR(t Πt b) < → +→ 20%, which put a contour on ([mmtV+tb, sincotω!)plane.Forsint¯RbL + mtVts cotω ! t0¯R.5,sL it+ setsmbV lowertb tan bound! t¯LbR of]⇧mΠ+aroundh.c. Πt ∼ t 150GeV .

bL sL + sL t, χ t, χ Πt 0 + γ + γ G Πt Πt t, χ t, χ t, χ − bL bR Πt bR Table 1: Lower bound of m + from b sγ (a) δg (b) b sγ Πt ZbL → → resulting lower bound on Πt+ mass + Nonetheless, much stronger bound is fromsinb ω sγ with0.26 top0.30 and Πt0.34loop contribution.0.40 0.46 As0.53 restricted low → to b, s, t,TC2sharesthesamepatternofyukawacouplingsas2HDMTypem + (GeV ) 551 500 440 396II, 363 332 Πt √ 1/2 + yukawa =(22GF ) u¯i(cot βmuiVijP2L +tan2 βVijmdj PR)dj H + h.c. 2 L mbmt cot ! dominates mbmt dominates !i,j (2√2G )1/2 [m V cot βt¯ b + m V cot βt¯ s + m V tan βt¯ b ] H+ + h.c.(23) References→ F t tb R L t ts R L b tb L R

[1] R. Sekhar Chivukula, N. D. Christensen,8 B. Coleppa and E. H. Simmons, Phys. Rev. D 80, 035011 (2009) [arXiv:0906.5567 [hep-ph]].

[2] R. S. Chivukula, E. H. Simmons, B. Coleppa, H. E. Logan and A. Martin, Phys. Rev. D 83, 055013 (2011) [arXiv:1101.6023 [hep-ph]].

[3] R. S. Chivukula, P. Ittisamai, E. H. Simmons and J. Ren, arXiv:1110.3688 [hep-ph].

[4] G. Burdman, C. Haluch and R. Matheus, arXiv:1112.3961 [hep-ph].

[5] O. Deschamps, S. Descotes-Genon, S. Monteil, V. Niess, S.T’JampensandV.Tisserand,Phys. Rev. D 82,073012(2010)[arXiv:0907.5135[hep-ph]].

[6] Search for neutral MSSM Higgs bosons decaying to tau lepton pairs in proton-proton collisions at sqrt(s) = 7 TeV with the ATLAS detector. ATLAS-CONF-2011-132. August 21, 2011.

10 Updated Ht Limits TC2 Dynamics

The limits above were derived in an effective ﬁeld theory (top triangle moose) for TC2 and related models: • A combination of topcolor dynamics and ETC give rise to the top quark mass: m m dyn + m ETC where t ⇡ t t the latter is only 0.5% - 10% of the total. N 2 f 2 = c m2 ln • The Pagels-Stokar relation t 2 t,dyn 2 8 mt,dyn ! relates sin f /v to the top mass ⌘ ⇧t 2 2 Nc The top-pion mass M = m t,ET C m t,dyn • t 4⇥2 f 2 should exceed the top mass ✓ t ◆ to respect bounds on t bH+ ! < • The dynamics imply MHt 2mt,dyn ⇠ LHC vs. TC2

Within the larger effective theory, one would then expect the TC2 model parameters to lie in the following ranges:

185 GeV

172 GeV

The data from FNAL, LHC, and b s appears to exclude! precisely this region. New DEWSB Model Directions

What kinds of models can evade the LHC constraints on neutral states in TC2 Models (colorons, technipions, top-Higgs)?

• Technicolor with substantial ETC contribution to mt ? g g Q t P P Q +/- t "t mt Q t g g FP

• Top-Seesaw Assisted Technicolor? • Stay Tuned! Conclusions Conclusions and Next Steps

• Avoiding large weak isospin violation is a challenge for dynamical EWSB. Models with new top-quark dynamics (topcolor, top seesaw) offer solutions; the top triangle moose is an effective theory interpolating among them • LHC can search for colorons, incorporating recent one- loop results for the K-factor and pT distribution.

•New states in the top sector includes T, H t and Πt states; all should be visible at LHC. Interplay among these states would signal that top dynamics plays a role in EWSB. • Recent LHC data on H WW,ZZ , combined with data on b s exclude! the most favored TC2 parameter !space. New models with heavier Ht (e.g. top- seesaw-assisted TC) are required.

What the LHC Can See (detail)

W’ searches: Belyaev, et al., arXiv:0708.2588 KK quarks: Chivukula, Christensen, Coleppa, Simmons arXiv:0906.5667 KK top quark, top-Higgs, and top-Pions Chivukula, Coleppa, Logan, Martin, Simmons arXiv:1101.6023 related work: 3-site: Ohl, Speckner arXiv:0809.0023 4-site: Hirn, Martin, Sanz arXiv:0712.3783 4-site: Accomando et al. arXiv:0807.5051 Reminder: 3-Site Model

R f1 f2 g g g 0 1 2 WWZ vertex L visibly altered M 25000 MTB Allowed Region Unitarity 20000 M << M KK fermion W 0 T,B violated mass (GeV) 15000

10000 2 4 M ✏tR 5000 ⇢ = 16 ⇡2 v2

0 Minimum 400 600 800 1000 1200 MW’ W’ mass (GeV) allowed 1-loop fermionic EW precision fermion corrections too large mass LHC Potential for Finding the W’

Integrated luminosity needed for 14 TeV LHC discovery of W’ Associated Production

Vector Boson Fusion KK Quark Pair Production

Variable Cut With basic identiﬁcation pTj >100 GeV and separation cuts on pTl >15 GeV jets and leptons, Missing ET >15 GeV ⌘ < 2.5 | j| a hard jet pT cut ⌘ < 2.5 | l| removes nearly all SM Rjj >0.4 background Rjl >0.4 Mll 89 GeV

MD = MD = 300 GeV 700 GeV 3000 50

0 0 200 400 600 800 1000 200 400 600 800 1000 References Mjll KK Quark Single Production # events Identiﬁcation and separation cuts on jets 14 and leptons, a hard MD = 800 GeV jet pT cut, and jet & lepton 7 rapidity cuts control the SM background 0 Variable Cut 400 600 800 1000 pTj hard >200 GeV 35 pTj soft >15 GeV pTl >15 GeV SM Missing ET >15 GeV ⌘ < 2.5 17 | j hard| ⌘ 2< ⌘ < 4 | j soft| | | ⌘l < 2.5 | | 0 Rjj >0.4 400 600 800 1000 Rjl >0.4 MT Key MASS Terms ψL0 ¯ 0 Top quark: t L0 tR g 01

ψL1 3 ~ Top-pions: 4⇡v Tr ⌃01⌃† g 1 12 ψR1

⇣ ⌘ g’ 12

2 All fermions (including top) : tR2,bR2 ✏ 0 u M ✏ ¯ ⌃ + ¯ + ¯ ⌃ uR R2 D L L0 01 R1 R1 L1 L1 12 0 ✏ d  ✓ dR ◆✓ R2 ◆ ideal delocalization says ✏2 = M 2 /2M 2 L W W 0 light fermion masses are still of the form m M ✏ ✏ f ⇡ D L fR each light mass value is tied to the value of ✏fR Top mass value is different... Top Mass

ψL0 Top mass matrix: 0

g ✏tL a t v sin! 01 Mt = MD . a 1 ✏tR ⌘ MD ψL1 ✓ ◆ g~ 1 ψR1

Perturbative diagonalization yields... g’ 12 2 2 2 ✏ + ✏ + ✏tL✏tR 2 m = v sin ! 1+ tL tR a t t 2( 1+a2) tR2,bR2 

Top mass now depends strongly on t , weakly on ✏tR

A large top mass no longer conﬂicts with M 2 ✏4 ⇢ = D tR making ✏ tR small to minimize ⇢ 16 ⇡2 v2

KK fermions are light enough to produce at LHC Top sector at LHC: Πt

± FNAL limits* on t → H b imply Πt is g t g t heavier than t, so the main production b t process is pp → t Πt → t t b. − − b b t t CMS studies** of H± → t b imply 30 -1 fb of data can ﬁnd a Πt up to 400 GeV

1 PtÆtb Note: Πt P ÆWH can also t ppt ÆP t 15 0.1 t PtÆtB decay to W Ht. PtÆZ' W L BR 0.01 PtÆZW' pb H

L 10 t t P

Æ 0.001 pp H s 5 200 400 600 800 1000

MPt GeV

0 H L 200 300 400 500 600 700

MPt GeV *V. M. Abazov et al. [D0 Collaboration], arXiv:0908.1811 **Lowette, D’Hondt, Vanlaer CERN-CMS-NOTE-2006-109

H L Top sector at LHC: Πt

0 ± 30 ppÆPt Pt Associated production pp → W* ppÆHP ± 25 t 0 → Ht Πt can provide useful ppÆHPt 20 conﬁrmation of the relationship L fb H 15 between Ht and Πt. s 10 Single production followed by 5 either Ht → WΠt or Πt → WHt 0 would be similarly informative. 200 300 400 500 600 700

MPt GeV

1.0 1 H Æ W+W- P Ætb t t H L Ht Æ ZZ Ht decay ± ° P ÆWH 0.8 HtÆ Pt W t t HtÆ tt 0.1 0 PtÆtB HtÆ Pt Z Πt decay 0.6 HtÆPt Pt PtÆZ' W HtÆ tT + h.c. BR BR 0.01 PtÆZW' 0.4

0.2 0.001

0.0 200 400 600 800 1000 200 400 600 800 1000 M GeV MHt GeV Pt

H L H L Constraints From Top-Pions

% Burdman & Kominis hep-ph/9702265

This and other b-ﬂavor-related issues pose additional constraints on model-building...

See also Buchalla et al. hep-ph/9510376; Burdman et al. 0012073; Simmons 0111032;