A Selection of Exotics with ATLAS

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A Selection of Exotics with ATLAS
Kamal Benslama Columbia University

• Strong Symmetry Breaking
• Extra Dimensions
• Little Higgs
• Compositeness
• New particles
• Plans for the Rome Workshop

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Introduction

• Hierarchy problem
• SUSY Elegant, not discussed here
• Technicolor
• . New strong interactions 1 TeV
• Extra Dimensions
• Gravity scale brought down to 1 TeV
• Little Higgs
• Higgs is pseudo-Goldstone boson ? 10TeV
• Possible new physics
• Excited fermions, contact interactions
• Extension of EW gauge group
• New gauge Bosons
• Unexpected

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Strong Symmetry Breaking
Technicolor
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Technicolor (1)

• TC
• - New strong interaction O(TeV) with
  Techniquarks condensates -gt EWSB
• no elementary scalar boson
• ETC w/walking coupling
• account for fermion masses
• Supress FCNC
• Predictions
• Technimesons resonances in WLWL and WLZL
  scattering

Ruled out by EW precision data
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Technicolor (2)
Rome

• ?T?

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Extra Dimensions

• Large Extra Dimensions
• TeV-1-sized Extra Dimensions
• Warped Extra Dimensions

Talk by V. Vassilakopoulos
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Large Extra Dimensions

• Large extra dimensions (gtgt 1/TeV)
• ADD model (Arkani, Dimopoulos, Dvali)
• SM particules in brane
• Gravity propagates in bulk (Xtra Ds)
• Hence new gravity scale MPL2 MD2? R?
• KK graviton excitations MD TeV for R lt mm

KK mode separation is very small e.g.
MD 1 TeV, n 2 ? R 0.08 mm ? R-1 2.6 x
10-3 eV n
4 ? R 1600 fm ? R-1 120 keV
? continuous spectrum
? high density of states compensates low
coupling (1/MPl ) ? chance
to observe effects at LHC
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ADD Graviton Emission
Rome

• Process
• Reach
• gG
• ?G

L. Vacavant and I. Hinchliffe, J. Phys. G
Nucl. Part. Phys. 27 (2001) 1839
Background calibrated by Z j -gt ll j
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TeV-1 Extra-Dimensions

• One extra dimension compactified on a S1/Z2
  orbifold
• radius of compactification small enough ? gauge
  bosons in the bulk
• fermions localized on
• a fixed point (M1 model) invariance under y ?
  -y
• opposite fixed points (M2 model) under y ? y
  2?R
• Kaluza-Klein spectra for Z(k), W(k) mk2 m02
  k2MC2
• for MC 4 TeV m1 4 TeV, m2 8 TeV
• ? look for pp ? ?(1)/Z(1) ? ll- on top of SM
  Drell-Yan

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TeV-1 Direct ?(1)/Z (1)

• Look at resonance in ll spectrum
• Observation up to 5.8 TeV with 100 fb-1

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Little Higgs

• Motivation
• Signatures

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Introduction

• Motivation
• H is Goldstone boson of larger group
• Cut-off ? introduced 10 TeV
• Divergences canceled by
• dm2Htop New colored fermion T
• dm2Hgauge New bosons WH, ZH, AH
• dm2HHiggs Higgs triplet
• Constraints
• T M lt 2TeV
• A, W, Z M lt 6TeV
• Higgs Triplet M lt 10GeV

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Heavy T
Rome
L 3105 pb-1

• Decay
• bW (50), tZ (25), th (25)
• tZ mode
• 3 leptons 1 b-jet
• th mode
• Confirmation mode
• 3 b-jets 1 lepton
• The heavy quark T can be observed for a mass up
  to 2TeV

L 3105 pb-1 ?1 ?2 S 12 M 1 TeV
ATLAS
tZ
wb
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New Higgs ?
Rome

• Production
• Via WW fusion
• Forward jet tag essential
• Decay
• WW to l?l?

300fb-1
At 1 TeV Significance 5 s if v gt 29 GeV
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Compositeness

• Excited quarks and leptons

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Introduction
Rome

• Motivation
• Fermionic generation explained by compositeness
• Quarks leptons have an underlying substructure
  characterized by a compositeness scale ?
• Interaction
• Contact interactions Scale ?
• Spectrum of excited states

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Excited Quarks Leptons

• Excited quarks
• Reach limit for q -gt q ? 6.5TeV
• - Reach for qw 7 TeV
• - Reach for qz 4.5 TeV
• ff1
• Excited electrons
• Reach 3 4 TeV for ? 6 TeV, 300fb-1

L 300 fb-1, L m
300fb-1
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New particles

• Heavy leptons
• New gauge bosons
• Leptoquarks

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Heavy Leptons
Rome

• Basics
• Look at sequential leptons 4th family
• Other models VF, Chiral F, Singlets F
• Final state llZZ
• Analysis
• gg DY
• 2l, 2Z (4jets)
• Bdg tt, VVjets

(e ??)
Reach 1 TeV
Depends on Z
Significance
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New Gauge Bosons
Atlas note in preparation
Rome
Full simulation, DC1 Z -gt ll

• Discriminating between models
• Look at ?x?, Asymmetry F-B
• Look at Z rapidity

Assuming SM coupling and Accounting for
interference
Reach for 100 fb-1 5 TeV
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Leptoquarks
Rome

• Motivation
• SM extension lepton-quark symmetry
• Study Scalar LQ

30 fb-1
Preliminary
- 2jets 2 leptons 1st and 2nd generation

Sensitivity M(LQ)1.3 TeV
Beta 1
- 2 jets Et 3rd generation
Sensitivity M(LQ) 1 TeV
Beta 0.5
1st generation
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Others

• Models with singlet neutrino
• Doubly Charged Higgs in LRSM
• Heavy Majorana Neutrinos
• Talk by V. Savinov
• Lepton Flavor Violation

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Plans for the Rome Workshop

It is the right time to ask ourselves the
following question What exotics can we do for
Rome? How are we going to proceed ?
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Plans for Rome Workshop

• Most of the exotics topics have already been done
  with ATLFAST
• Our goal is to to redo most of them with full
  simulation using Rome-Layout
• Study reconstruction with Rome-Layout, including
  noise and pile-up
• Develop tools for TeV scale analyses
• Also detector studies at the TeV scale
• - Energy Calibration
• - Reconstruction efficiency
• - Refining energy resolution
• - PID
• - b-tagging
• - Forward-jets tagging

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What Exotics for Rome?
di-leptons channels

Z, G, H.
di-jets channels

• Signal of W, Z, excited quarks,..ect

• Signals of heavy scalar Higgs,
• Strong Dynamics VV, G, Z,

WW, WZ, ZZ
Wb, Zb, Hb

• Little Higgs Model, technipions

?jets, l? lZ

Excited fermions

• Leptoquarks

ljets
MET jets

• LED, leptoquarks

• Non resonante excess of events

ll, ??, jj, tt

• Black Holes

all SM particles
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Detector Studies

• No Physics without good understanding of the
  detector

For High Energy Particles
energy Calibration Reconstruction
efficiency Refining energy resolution Charge
misidentification for electrons and
muons PID b-tagging
DC1
Z
recalibrated
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Preliminary Studies with Rome-Layout
q
q

• Two High Pt leptons
• two forward jets
• Small MEt
• Main background from qqww

q
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Rome
DC2 vs Rome-Layout
Pt Lepton
E Jet1
DC2 Rome-Layout
DC2 Rome-Layout
DC2 Rome-Layout
DC2 Rome-Layout
MET
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N. American Contributions

• To the best of my knowledge

Physics Studies
Institution
Contact Person
H in LRSM and LHM RS Graviton H.E. e, gamma, PID
Columbia
Kamal
Hampton
K. Baker
RS Graviton
Pittsburg
Vladimir
W,Z , LFV
Z, excited e, quarks Leptoquarks,
Technicolor Jets reconsruction
G.Azuelos
Montreal
K. Loureiro
Wisconsin
Black Holes
Ian
(Litte Higgs, LED),UED?
LBL
Not for Rome
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Roadmap for Rome

• In order to ensure a high US contribution to the
  Exotics Physics in Rome, more people need to get
  involved in the analyses.
• People with the same physics interests are
  encouraged to work together.
• Studies of the detector response at the TeV scale
  is needed not only for Rome, but beyond.
• Calibration, PID and tools development for TeV
  scale analyses should get the same priority as
  physics analyses.
• People already involved in the Exotics group will
  be happy to
• help new members Analyses, Software, MC
  samples,etc
• The Rome Workshop will be a golden opportunity to
  test the software and the computing model and
  also to test the
• US Physicists Compatibility model
• Our Success in Rome and beyond will depend
  on how well we will work together.

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Invitation
Compositeness
Technicolor
Little Higgs
Extra Dimensions
LFV
New particles
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