The considerable center-of-mass energy and luminosity provided by the Large
Hadron Collider (LHC) will ensure a discovery reach for new particles which
extends well into the multi-TeV region. ATLAS and CMS have carried out many
studies of the implications of this capability for Beyond the Standard Model
physics. In this paper, we summarize some key results of studies involving
non-susy models, such as extra-dimensions, little higgs, compositeness, and
left-right symmetric models.Comment: 7 pages, conferenc

Benslama, Kamal

English

arXiv

The considerable center-of-mass energy and luminosity at the LHC will ensure a discovery reach for new particles which extends well into the mlti-TeV region. ATLAS and CMS carried out many studies of the implications of this capability for Beyond the Standard Model Physics. In this talk, I will focus on studies involving extra-dimensions, little higgs, strong symmetry breaking, compositeness and new gauge bosons

Benslama, K

CERN Document Server

K. Benslama Hadron Collider Symposium 1Kamal BenslamaColumbia UniversityOn behalf of the ATLAS and CMSCollaborationsMay 23, 2006Hadron Collider SymposiumOther Exotic Scenarios at the LHCK. Benslama Hadron Collider Symposium 2BSM ScenariosΛ−~10~ 17MPlankEWmMMδNew Physics at TeVScale to stabilize mHSUSYNew particles at TeV scalePrevious talkExtra DimensionsAdditional dimensions New states at TeVScale Other Scenarios of New Physics- Leptoquarks- Excited fermions- New gauge bosonsLittle HiggsSM embedded in largergroup New particles at TeV scaleTechnicolorNew strong interactions break EW symmetryNew particles at TeVscaleK. Benslama Hadron Collider Symposium 3BSM Physics: Real life…“deviation-from-SM” hunting byexperimentalists,then “model hunting” by theorists-It is a real  challenge!It’s a complicated environmentK. Benslama Hadron Collider Symposium 4Large Extra Dimensions9Large extra dimensions (>> 1/TeV)– ADD model (Arkani, Dimopoulos, Dvali)– SM particules on brane– Gravity propagates in bulk (Xtra Ds)• Hence new gravity scale MPL2 ~ MD2+δ Rδ• KK graviton excitations   MD ~ TeV for R < mmKK mode separation is very small:e.g.: MD = 1 TeV, n = 2 ⇒ R = 0.08 mm ⇒ R-1 = 2.6 x 10-3 eVn = 4 ⇒ R = 1600 fm  ⇒ R-1 = 120 keV→ continuous spectrum→ high density of states compensates low coupling (~1/MPl )Æ chance to observe effects at LHCK. Benslama Hadron Collider Symposium 5ADD: Graviton Emission9Process9Reach– gG– γG  jets + ( ) ( )( )( ),,γγ⎫→ ⎪→ +⎬⎪→ ⎭k kkT Tkqq gG Gqg qG E Egg gG 100 fb-1ATLASK. Benslama Hadron Collider Symposium 6ADD: Virtual Graviton9 Final state– Use effective scaleMs (σ diverges if δ≥2)9 Observables – Excess in ll & γγ– γγ more central than SM, , , ( , ...)qq gg WW t tγγ→ ll  TeVr     eachT: eV: ~ 5.1: ~ 6.6SSMMγγ⎧⎨⎩llATLASηdNdηpp→γγn=3Mll10fb-1MγγK. Benslama Hadron Collider Symposium 7TeV-1 Extra Dimension• One extra dimension compactified on a S1/Z2 orbifold• radius of compactification small enough Î gauge bosons in the   bulk• fermions localized on:• a fixed point (M1 model): invariance under y Æ -y• opposite fixed points (M2 model):    under y Æ y + 2πR• Kaluza-Klein spectra for Z(k), W(k) : mk2 = m02 + k2MC2• for MC = 4 TeV:  m1 = 4 TeV, m2 = 8 TeVÎ look for pp Æ γ(1)/Z(1) Æ l+l- on top of SM Drell-YanK. Benslama Hadron Collider Symposium 8TeV-1: Direct γ(1)/Z (1)M2M1SM4 TeVLook for resonances in ll spectrumATLASObservation up to ~ 5.8 TeV with100 fb-1 For 1 TeV< m <2.5 TeVup to ~ 8 TeV with 100fb-1K. Benslama Hadron Collider Symposium 9TeV-1: Asymmetry9 Look at Forward-Backward asymmetry100fb-1M2G*Z’M1ATLAS100 fb-1K. Benslama Hadron Collider Symposium 10Randall-Sundrum9Motivation– 2 branes (TeV & Planck ) connected by 1 warped ED– Coupling of KK states ~ 1/Λπ– Graviton excitations– Constraints ; 35 TeVckrpl cM e krππ ππ−Λ = ⇒ Λ      avec  11, ( ) 03.83ππ−= == Λck rn n nPlm kx e J xkmM0.01 < k/Mpl < 0.1K. Benslama Hadron Collider Symposium 11RS: Graviton ResonanceCMSCMS~1.3 TeVK. Benslama Hadron Collider Symposium 12RS: Graviton Spin9 Look at angular distributionATLAS90% exclusion of spin-1for mG < 1.7 TeVK. Benslama Hadron Collider Symposium 13Little Higgs: Heavy T9 The heavy quark T can be observed for a mass up to ~2TeVL = 3·105 pb-1λ1 = λ2S = 12M = 1 TeVATLASL = 3·105 pb-1K. Benslama Hadron Collider Symposium 14Little Higgs: AH and ZHSignal : di-lepton resonanceReach up to 5.7 TeV depending on the θ angleK. Benslama Hadron Collider Symposium 15Technicoloro At least 3 charged leptonswith pT > 25 GeVo pT(W), PT(Z) > 40 GeVo Use polarization of technirhoATLAS9 ρT± 30fb-1WZWZWZK. Benslama Hadron Collider Symposium 16Excited Quarks & Leptons9 Excited quarks– Reach limit for q* -> q γ6.5TeV- Reach for qw: 7 TeV- Reach for qz: 4.5 TeVf=f’=19 Excited electrons9 Reach: ~ 3 – 4 TeV for Λ = 6 TeV,  300fb-1L = 300 fb-1, Λ = m*ATLASK. Benslama Hadron Collider Symposium 17Leptoquarks9Motivation– SM extension: lepton-quark symmetry9 Study: Scalar LQqqllLQLQ −+→- 2jets + 2 leptons: 1st and 2ndgenerationSensitivity: M(LQ)~1.3 TeVBeta= 1- 2 jets + Et: 3rd generationqqLQLQ νν→Sensitivity: M(LQ) ~ 1 TeVBeta= 0.530 fb-11st generationATLASK. Benslama Hadron Collider Symposium 18New Gauge Bosons (I)CMSA very low luminosity, less than 0.1 fb-1, should be sufficient to discover Z' bosons at 1 TeVK. Benslama Hadron Collider Symposium 19New Gauge Bosons (II)CMSK. Benslama Hadron Collider Symposium 20Doubly Charged HiggsGeVkkk 250~2221 +=L-R  symmetric model would be a natural extension of the SM¾ SU(2)L x SU(2)R x U(1)B-L¾ predicts new fermions: heavy Majorana neutrino ¾ predicts new gauge bosons:WR¾ predicts new Higgs sector  (if Lagrangian is invariant under  symme) try)0001,2 1,2( , , )( , ,,R R R RL L L L L Rφ φ+ +++ ++±∆ = ∆ ∆ ∆∆ = ↔∆ ∆ ∆Rν1k 2k2 2 22 2 2 211 2 /~cos 1 4 /LW LW z LM kM kνρ θ ν+= +Lν9L G eVν ≤64.0,2/222 ≈== LRRRW gggm R νParameters:Two high pT leptons with same chargeTwo high pT jetsIn this analysis:K. Benslama Hadron Collider Symposium 21Discovery Reach−−++−−++ →∆∆ llllLL(a) 100 fb-1(b) 300 fb-1Dashed =4 leptons are observedFull = 3 leptons are observed~1.2 TeVee,µµ(a) 100 fb-1(b) 300 fb-1Tevatron~1.4 TeVtau tau(a) 100 fb-1(b) 300 fb-1~400GeVATLASK. Benslama Hadron Collider Symposium 22SummaryLHC will explore the TeV scale in detail with direct discoverypotential up to m ~ 5-6 TeVExtra Dimensions?Black Holes???Little Higgs?New Gauge Bosons? Technicolor?Excited electrons?K. Benslama Hadron Collider Symposium 23Conclusion9 403 days from now, particle physics will enter a new epoch of its history.9 The LHC will address many of the leading questions in particle physics:- Is nature supersymmetric?- Are there extra dimensions of space?- What unknown mechanism gives mass to particles?Solving these mysteries will be an important chapter in the history of science.K. Benslama Hadron Collider Symposium 24Backup SlidesK. Benslama Hadron Collider Symposium 25ATLAS & CMSK. Benslama Hadron Collider Symposium 26ATLAS & CMS at the Beginning?3 layers of pixels No EE chambersK. Benslama Hadron Collider Symposium 27The ATLAS Detector Inner Detector (2T solenoid, |η|<2.5):Calorimetry:* electromagnetic, |η|<3.2* hadronic (central, |η|<1.7)* hadronic (endcaps, 1.7<|η|<3.2)* hadronic (forward, 3.2<|η|<4.9)Muon system (~4T toroid, |η|<2.7):⊕ tp t tσ p 0.05% GeV ×p 1%⊕ Eσ E 10 % GeV E 0%⊕ Eσ E 50 % GeV E 3%⊕ Eσ E 60 % GeV E 3%⊕ Eσ E 100 % GeV E 5%≈ tp t tσ p 10% for p (µ) 1 TeV/c K. Benslama Hadron Collider Symposium 28CMS DetectorK. Benslama Hadron Collider Symposium 29ATLAS Trigger & PhysicsK. Benslama Hadron Collider Symposium 30Charge sign misidentificationK. Benslama Hadron Collider Symposium 31Jets Calibration using γ/jet sampleK. Benslama Hadron Collider Symposium 32Large Extra-D: Direct ProductionJet+MET Gamma+METK. Benslama Hadron Collider Symposium 33Extra-D ModelsLarge Extra-D: Virtual ProductionRS GravitonK. Benslama Hadron Collider Symposium 34Constraints on large EDconstraint δ=2 δ=3max R(mm)min MD(TeV)max R(mm)min MD(TeV)Gravitational force law 0.2 0.6SN1987A cooling by graviton emission7 x 10–410309 x 10–7 0.82.5Diffuse cosmic ray background (G(k) → γγ )other reheating scenariosdecays after SN explosion9 x 10–5251674502 x 10–7 1.92230LEP: γ G, ZG, virtual ~ 1 TeVTevatron ~ 1 TeVheating of neutron stars(trapped G(k) decaying)8 x 10-69017003.5 x 10-8560K. Benslama Hadron Collider Symposium 35 Radion9Motivation– Scalar field representing fluctuations of the distance of the 2 branes– To stabilize krcπ ~ 35  (Golberger & Wise)9Radion properties– Higgs-like couplings– Mixing to Higgs ξ9SignalK. Benslama Hadron Collider Symposium 36Radion9Other signals–99Discrimination Higgs/Φ– Difficult at LHC– Look at Γ & BR mods(Rizzo et al)hh bbφ γγ→ →hh bbφ τ τ+ −→ →ξ Λφ (ΤeV) mφ=300 mφ=6000 1 4 430 10 333 -1/6 1 2 571/6 10 250 -hh bbφ γγ→ →Required luminosity (fb-1) for 5σ discoveryK. Benslama Hadron Collider Symposium 37Black HolesK. Benslama Hadron Collider Symposium 38New Higgs Φ++9 Production– Via WW fusionForward jet tag essential9 Decay– W+W+ to l+νl+νW+φ++W+ 300fb-1At 1 TeV; Significance: 5 σ if v’ > 29 GeVK. Benslama Hadron Collider Symposium 39Heavy Gauge BosonsZhe+e- + µ+µ- + τ+τ-BRcot θAccessible region for 5σ discoveryCross section and Br. fractionsK. Benslama Hadron Collider Symposium 40Heavy Leptons9 Basics– Look at sequentialleptons: 4th family– Other models: VF, Chiral F, Singlets F– Final state llZZ9 Analysis– gg & DY– 2l, 2Z (4jets)– Bdg: tt, VV+jetsReach ~ 1 TeVDepends on Z’'5 0 0 G eV7 0 0 G eVLZMM==Significance

Other Exotic Scenarios at the LHC

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