Beyond the Standard Model Highlights of Experimental Results from ATLAS & CMS

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7/7/14 1

Beyond the Standard Model

Highlights of Experimental Results from ATLAS & CMS

Frank Würthwein UCSD

ICHEP 2014

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Many thanks to 22 Parallel Session Speakers from ATLAS & CMS…

•  Javier Duarte, Jovan Mitrevski, Nick McColl, Joao Firminho Da Costa, Robert Schoefbeck, Andrée Robichaud-Véronneau,

Owen Long, Roger Caminal Armadans, Pablo Martinez, Luca Fiorini, Paul Lujan, Matthew King, Jan Kretzschmar, Steven Lowette, Ning Zhou, Francesco Santanastasio, Koji Terashi, Francesco Romeo, Tim Andeen, Roman Kogler, Frederick Rühr, and Lesya Shchutska.

•  … for presenting 54 papers that came out in 2014, out

of which 12 were presented for the first time at ICHEP.

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Vast range of theoretical ideas

7/7/14 ICHEP 2014 3

24 June 2013

Anything Else?

• Could organize into

“signature-based”

this stage

7

Hitoshi Murayama

Lots of possibilities!

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Vast # of results to cover

ATLAS

•  Exotics:

–  10 pub + 29 conf. notes

https://twiki.cern.ch/twiki/bin/view/AtlasPublic/ExoticsPublicResults

•  SUSY:

https://twiki.cern.ch/twiki/bin/view/AtlasPublic/SupersymmetryPublicResults

•  BSM Higgs:

–  3 pub + 5 conf. notes

https://twiki.cern.ch/twiki/bin/view/AtlasPublic/HiggsPublicResults

CMS

•  Exotics:

–  10 pub + 18 PAS

https://twiki.cern.ch/twiki/bin/view/CMSPublic/PhysicsResultsEXO

•  Beyond 2 Generations:

–  6 pub + 14 PAS

https://twiki.cern.ch/twiki/bin/view/CMSPublic/PhysicsResultsB2G

•  SUSY:

–  12 pub + 21 PAS

https://twiki.cern.ch/twiki/bin/view/CMSPublic/PhysicsResultsSUS

•  BSM Higgs:

–  6 pub + 4 PAS

https://twiki.cern.ch/twiki/bin/view/CMSPublic/PhysicsResultsHIG

even when considering only 8TeV results

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ATLAS

•  Exotics:

•  SUSY:

–  12 pub + 37 conf. notes

•  BSM Higgs:

CMS

•  Exotics:

–  10 pub + 18 PAS

–  6 pub + 14 PAS

•  SUSY:

–  12 pub + 19 PAS

•  BSM Higgs:

–  6 pub + 4 PAS

7/7/14 ICHEP 2014 5

Impossible to cover all !!!

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ATLAS

•  Exotics:

•  SUSY:

•  BSM Higgs:

CMS

•  Exotics:

–  10 pub + 18 PAS

–  6 pub + 14 PAS

•  SUSY:

–  12 pub + 19 PAS

•  BSM Higgs:

–  6 pub + 4 PAS

Impossible to cover all !!!

Instead, attempt to cover diversity of

experimental signatures with a few examples.

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ATLAS

•  Exotics:

•  SUSY:

–  12 pub + 37 conf. notes

•  BSM Higgs:

CMS

•  Exotics:

–  10 pub + 18 PAS

–  6 pub + 14 PAS

•  SUSY:

–  12 pub + 19 PAS

•  BSM Higgs:

–  6 pub + 4 PAS

7/7/14 ICHEP 2014 7

Impossible to cover all !!!

Instead, attempt to cover diversity of

experimental signatures with a few examples.

For each example shown in body of talk, the corresponding results from the other experiment are presented in the

backup slides.

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Outline

•  Introduction

•  Resonances

•  Dark Matter

•  Long lived particles

2->2

2->1 Simple, e.g. ll,jj,…

Complex, e.g. tt,WZ,th,…

Anti-social: pp -> nothing

Semi-social: compressed spectra, …

Social: DM at the end of cascades

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Standard Model Backgrounds

7/7/14 ICHEP 2014 9

[GeV/c]

Jet p

T

30 40 100 200 1000 2000

GeV/c pb dy

T

dp σ

2

d

10-5

10-3

10-1

10 103

105

107

109

1011

1013pp s = 8 TeV CMS Preliminary

21

(low PU runs) = 5.8 pb-1

open: Lint

(high PU runs) = 10.71 fb-1

filled: Lint

⊗NP NNPDF 2.1 NLO

5)

× 10 0.0 <|y|< 0.5 (

4)

× 10 0.5 <|y|< 1.0 (

3)

× 10 1.0 <|y|< 1.5 (

2)

× 10 1.5 <|y|< 2.0 (

1)

× 10 2.0 <|y|< 2.5 (

0)

× 10 2.5 <|y|< 3.0 (

-1)

× 10 3.2 <|y|< 4.7 (

5)

× 10 0.0 <|y|< 0.5 (

4)

× 10 0.5 <|y|< 1.0 (

3)

× 10 1.0 <|y|< 1.5 (

2)

× 10 1.5 <|y|< 2.0 (

1)

× 10 2.0 <|y|< 2.5 (

0)

× 10 2.5 <|y|< 3.0 (

-1)

× 10 3.2 <|y|< 4.7 (

[pb] σ Production Cross Section,

10-1

1 10 102

103

104

105

CMS Preliminary

Oct 2013

W ≥1j ≥2j ≥3j ≥4j Z ≥1j ≥2j ≥3j ≥4j tt 1j 2j 3jt_tchantW ttZ Wγ Zγ WW WZ ZZWW

→ γ γ

qqll EWWVγ

σ in exp. ∆ σH

Th. ∆ ggHqqHVBF VH ttH

CMS 95%CL limit

-1) 5.0 fb 7 TeV CMS measurement (L ≤

-1) 19.6 fb

≤ 8 TeV CMS measurement (L 7 TeV Theory prediction 8 TeV Theory prediction

1-lepton & MET cross section

~ x10 6 smaller than all hadronic

Dilepton same-sign & MET

~ x10 12 smaller than all hadronic.

W & jets

Z & jets

top & jets

Higgs ~x10 10 smaller than all hadronic

Leptons, MET, Z, h, …

are excellent probes in

search for BSM physics

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Standard Model Backgrounds

[GeV/c]

Jet p

T

30 40 100 200 1000 2000

GeV/c pb dy

T

dp σ

2

d

10-5

10-3

10-1

10 103

105

107

109

1011

1013pp s = 8 TeV CMS Preliminary

21

(low PU runs) = 5.8 pb-1

open: Lint

(high PU runs) = 10.71 fb-1

filled: Lint

⊗NP NNPDF 2.1 NLO

5)

× 10 0.0 <|y|< 0.5 (

4)

× 10 0.5 <|y|< 1.0 (

3)

× 10 1.0 <|y|< 1.5 (

2)

× 10 1.5 <|y|< 2.0 (

1)

× 10 2.0 <|y|< 2.5 (

0)

× 10 2.5 <|y|< 3.0 (

-1)

× 10 3.2 <|y|< 4.7 (

5)

× 10 0.0 <|y|< 0.5 (

4)

× 10 0.5 <|y|< 1.0 (

3)

× 10 1.0 <|y|< 1.5 (

2)

× 10 1.5 <|y|< 2.0 (

1)

× 10 2.0 <|y|< 2.5 (

0)

× 10 2.5 <|y|< 3.0 (

-1)

× 10 3.2 <|y|< 4.7 (

[pb] σ Production Cross Section,

10-1

1 10 102

103

104

105

CMS Preliminary

Oct 2013

W ≥1j ≥2j ≥3j ≥4j Z ≥1j ≥2j ≥3j ≥4j tt 1j 2j 3jt_tchantW ttZ Wγ Zγ WW WZ ZZWW

→ γ γ

qqll EWWVγ

σ in exp. ∆ σH

Th. ∆ ggHqqHVBF VH ttH

CMS 95%CL limit

-1) 5.0 fb 7 TeV CMS measurement (L ≤

-1) 19.6 fb

≤ 8 TeV CMS measurement (L 7 TeV Theory prediction 8 TeV Theory prediction

Cross sections decrease exponentially

with jet pT and # of jets.

W & jets

Z & jets

top & jets

Define:

H T = Σ p T of jets above threshold meff = H T + MET

S = meff + Σ p of leptons above threshold

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α

T

0 0.5 1 1.5 2 2.5 3

Events / 0.05

1 10 10

2

10

3

10

4

10

5

10

6

10

7

10

8

= 8 TeV s

-1, = 11.7 fb CMS, Lint

≤ 3 njet

2 ≤

Data

Standard model Non-multijet Multijet

Reference model D2

Kinematic Endpoints

7/7/14 ICHEP 2014 11

1 ℓ , ≥2 jets,#

MET > 50GeV #

Simulation

keep

MH0C010C!#CN#OPOQ)JP!!RS"

NC+)9*DE8T"%+97%Q"

;/%12',H"('"#$%&(2',/.(#15&#?(T,/"<#0%(H#$,#=1"(

@  +#$."+'(-,$"%+(#/-(.12,/*@,/-2%"-(FQ(5$*-2%0*/(

@   #15&#?(2'"-(#'(Z\8G@T,11"$[P(

(

U"

! T

0 0.5 1 1.5 2 2.5 3

Events / 0.05

1 10 10

2

10

3

10

4

10

5

10

6

10

7

10

8

= 8 TeV s

-1

, = 11.7 fb CMS preliminary, L

int

" 3 n

jet

"

2

Data

Standard model Non-multijet Multijet

Reference model D2

! T = E

^T

jet 2

M T

di-jet

!

= 1

2 ! 1 " ( # H T / H T ) 1 " (H T miss / H T ) 2

multi-jet

! ### " ### $

N"<#,/,/.(=#%T.$*2/-'("'0<#+"-(

)$*<(%*/+$*1($".,*/'(,/(-#+#(

@   :#X*$P(B]9"+'U(^]9"+'U(L=#$]9"+'(

( _,//"-(,/(R`a(',./#1($".,*/'S(

@   Y2<="$(*)(X"+'(RC@FU(bcdS(

@   Y2<="$(*)(=@X"+'(RDUEUCUFUbcdS(

@   7 ? (Re(=,/'()$*<(Caf(+*(bceaf(Q"gS(

9#-(:#$$*2%&"(@(:*$,*/-(AB(CDEF(

Transverse mass for:

Hadronic event clustered into 2 megajets

W → µν , e ν , τν

t → Wb → l ν b

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Boosted V Topology

7/4/14 Francesco Santanastasio (CERN) 11

•  Low p T boson

–  Large opening angle

•  Energetic boson

–  M resonance = 2 TeV –  p T,V ~ 1 TeV

–  M V ~ 100 GeV

V

€

Δ R qq min ≈ 0.2

quark

anti-quark

V Y

Δ R ~ 0.2

€

Δ R qq min ≈ Δ θ qq min ≈ 2 M V p T , V

Vqq decay:

Jet Merging

Jet Substructure

7/7/14 ICHEP 2014 12

Boosted V Topology

7/4/14 Francesco Santanastasio (CERN) 11

•  Low p T boson

–  Large opening angle

•  Energetic boson

–  M resonance = 2 TeV –  p T,V ~ 1 TeV

–  M V ~ 100 GeV

V

€

Δ R qq min ≈ 0.2

quark

anti-quark

V Y

Δ R ~ 0.2

€

Δ R qq min ≈ Δ θ qq min ≈ 2 M V p T , V

Vqq decay:

Jet Merging

For W,Z,h Bosons of M ~ 100GeV and jet cones of ΔR < 0.5

=> cones start merging at p > ~ 200GeV

0.5

pruned jet mass (GeV)

0 50 100 150

Normalized distribution

0 0.2 0.4 0.6

0.8 < 600 GeV

QCD 400 < pT

+ <PU>=22 + sim.

< 1.4 TeV QCD 1.1 < pT

+ <PU>=22 + sim.

< 600 GeV 400 < pT

WL

+ <PU>=22 + sim.

< 1.4 TeV

T

1.1 < p WL

+ <PU>=22 + sim.

CA R=0.8

|<2.4 η

|

= 8 TeV, dijets s

CMS Preliminary Simulation,

Jet Substructure

•  1) Jet trimming, pruning, filtering, …

–  Remove soft component of jet, reducing effects of pileup and UE

•  2) Substructure variables

–  Built from subjets after jet declustering m jet

~ m q ~ 0

BACKGROUND m jet ~ m W

~ 80 GeV +

Dipolar structure

SIGNAL

Jet mass N-subjettiness τ N (topological

compatibility with N subjets)

CMS arXiv:1405.1994 A TLAS-CONF-2014-039 CMS arXiv:1405.1994

Momentum Balance

Plenty of alternatives at CMS-JME-13-006 and ATL-PHYS-PUB-2014-004

Jet Substructure

•  1) Jet trimming, pruning, filtering, …

–  Remove soft component of jet, reducing effects of pileup and UE

•  2) Substructure variables

–  Built from subjets after jet declustering m jet

~ m q ~ 0

BACKGROUND m jet ~ m W

~ 80 GeV +

Dipolar structure

SIGNAL

Jet mass N-subjettiness τ N (topological

compatibility with N subjets)

CMS arXiv:1405.1994 A TLAS-CONF-2014-039 CMS arXiv:1405.1994

Momentum Balance

Plenty of alternatives at CMS-JME-13-006 and ATL-PHYS-PUB-2014-004

Background Signal

CMS-JME-13-006

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Typical Search Strategy

•  Define “low bkg” signal regions using the ingredients from previous slides.

•  Extrapolate expected bkg yields from carefully chosen bkg rich samples.

–  Derive extrapolation factors from mix of data and simulation.

•  Measure accuracy of extrapolation in independent control regions in data and simulation.

7/7/14 ICHEP 2014 13

Brains (Strategy)

Brawn

(Execution) => Success

+

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2->2

2->1 Simple, e.g. ll,jj,…

Complex, e.g. tt,WZ,th,…

Resonances

New in 2014 New at ICHEP

ATLAS-CONF-2014-030 CMS-PAS-B2G-14-003 CMS-PAS-B2G-14-002 CMS-PAS-B2G-14-003

CMS-PAS-EXO-13-008

CMS-PAS-EXO-12-030 CMS-PAS-EXO-12-032

arXive: 1406.4456 ATLAS-CONF-2014-039 ATLAS-CONF-2014-036 arXive: 1405.4123

arXive: 1406.5171 arXive: 1405.3447 arXive: 1405.1994 CMS-PAS-EXO-12-020

15 new papers

In 2014 4 new papers at ICHEP

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Dilepton Mass Spectrum

7/7/14 ICHEP 2014 15

10

TABLE III. Summary of systematic uncertainties on the expected numbers of events at a dilepton mass of m

ℓℓ

= 2 TeV, where n/a indicates that the uncertainty is not applicable.

Uncertainties < 3% for all values of m

ee

or m

µµ

are neglected in the respective statistical analysis.

Source (m

ℓℓ

= 2 TeV) Dielectrons Dimuons Signal Backgr. Signal Backgr.

Normalization 4% n/a 4% n/a

PDF variation n/a 11% n/a 12%

PDF choice n/a 7% n/a 6%

α

s

n/a 3% n/a 3%

Electroweak corr. n/a 2% n/a 3%

Photon-induced corr. n/a 3% n/a 3%

Beam energy < 1% 3% < 1% 3%

Resolution < 3% < 3% < 3% 3%

Dijet and W + jets n/a 5% n/a n/a

Total 4% 15% 4% 15%

TABLE IV. Summary of systematic uncertainties on the expected numbers of events at a dilepton mass of m

ℓℓ

= 3 TeV, where n/a indicates that the uncertainty is not applicable.

Uncertainties < 3% for all values of m

ee

or m

µµ

are neglected in the respective statistical analysis.

Source (m

ℓℓ

= 3 TeV) Dielectrons Dimuons Signal Backgr. Signal Backgr.

Normalization 4% n/a 4% n/a

PDF variation n/a 30% n/a 17%

PDF choice n/a 22% n/a 12%

α

s

n/a 5% n/a 4%

Electroweak corr. n/a 4% n/a 3%

Photon-induced corr. n/a 6% n/a 4%

Beam energy < 1% 5% < 1% 3%

Resolution < 3% < 3% < 3% 8%

Dijet and W + jets n/a 21% n/a n/a

Total 4% 44% 4% 23%

MS. However, such events are rare and the corresponding systematic uncertainty is negligible over the entire mass range considered. This is an improvement on previous ATLAS publications [17], which used a very conservative, and much larger, estimate: 6% at 2 TeV. In addition, the uncertainty on the resolution due to residual misalign- ments in the MS propagates to a change in the steeply falling background shape at high dilepton mass and in the width of signal line shape. The potential impact of this uncertainty on the background estimate reaches 3% at 2 TeV and 8% at 3 TeV. The eﬀect on the signal is negligible. As for the dielectron channel, the momentum scale uncertainty has negligible impact in the dimuon channel search.

Mass-dependent systematic uncertainties that change the expected number of events by at least 3% anywhere in the m ℓℓ distribution are summarized in Tables III and IV for dilepton invariant masses of 2 TeV and 3 TeV, respectively.

Events

10-1

1 10 102

103

104

105

106

107

Data 2012 γ* Z/

Top quark Dijet & W+Jets Diboson Z’ SSM (1.5 TeV) Z’ SSM (2.5 TeV) ATLAS

ee Z’ →

L dt = 20.3 fb-1

∫

s = 8 TeV

[TeV]

m

ee

0.08 0.1 0.2 0.3 0.4 0.5 1 2 3 4

Data/Expected

0.60.8 1 1.21.4

Events

10-1

1 10 102

103

104

105

106

107

Data 2012 γ* Z/

Top quark Diboson Z’ SSM (1.5 TeV) Z’ SSM (2.5 TeV) ATLAS

µ µ Z’ →

L dt = 20.5 fb-1

∫

s = 8 TeV

[TeV]

µ

m

µ

0.08 0.1 0.2 0.3 0.4 0.5 1 2 3 4

Data/Expected

0.60.8 1.21 1.4

FIG. 2. Dielectron (top) and dimuon (bottom) invariant mass (m

ℓℓ

) distributions after event selection, with two se- lected Z

SSM^′

signals overlaid, compared to the stacked sum of all expected backgrounds, and the ratios of data to back- ground expectation. The bin width is constant in log m

ℓℓ

. The green band in the ratio plot shows the systematic uncertainties described in Sec. IX.

X. COMPARISON OF DATA AND BACKGROUND EXPECTATIONS

The observed invariant mass distributions, m ee and m µµ , are compared to the expectation from SM backgrounds after final selection. To make this comparison, the sum of all simulated backgrounds, with the relative contributions fixed according to the respective cross- sections, is scaled such that the result agrees with the observed number of data events in the 80 - 110 GeV normalization region, after subtracting the data-driven background in the case of the electron channel. The scale factors obtained with this procedure are 1.02 in the dielectron channel and 0.98 in the dimuon channel. It is this normalization approach that allows the mass-independent uncertainties to cancel in the statistical analysis.

Figure 2 depicts the m ℓℓ distributions for the dielectron and dimuon final states. The bin width of the histograms is constant in log m ℓℓ , chosen such that a possible signal peak spans multiple bins and the shape is not impacted

Table 3: Expected and observed event yields in the dimuon channel. The predicted yields are shown for SM background as well as for SM + CI for several CI signal scenarios. The quoted errors consist of both the statistical and systematic uncertainties added in quadrature.

Process m

µµ

[GeV]

400 – 550 550 – 800 800 – 1200 1200 – 1800 1800 – 3000 3000 – 4500 Drell-Yan 670 ± 50 217 ± 18 45 ± 5 5.9 ± 0.8 0.58 ± 0.12 0.027 ± 0.008 Top quarks 128 ± 10 16.3 ± 1.4 1.66 ± 0.11 0.103 ± 0.007 < 0.005 < 0.002

Diboson 47.6 ± 2.7 15.3 ± 0.9 3.75 ± 0.26 0.556 ± 0.030 0.056 ± 0.005 < 0.003 Photon-Induced 34 ± 34 13 ± 13 3.3 ± 3.3 0.5 ± 0.5 0.07 ± 0.07 < 0.006

Total SM 880 ± 60 261 ± 22 54 ± 6 7.2 ± 1.0 0.71 ± 0.14 0.032 ± 0.009

Data 814 265 47 7 1 0

SM + CI ( Λ

⁻_LL

= 14 TeV) 900 ± 60 285 ± 23 70 ± 6 14.4 ± 1.2 2.89 ± 0.33 0.18 ± 0.04 SM+CI (Λ

⁻_LL

= 20 TeV) 870 ± 60 265 ± 23 58 ± 6 10.0 ± 1.1 1.49 ± 0.18 0.103 ± 0.022 SM+CI (Λ

⁻_LR

= 14 TeV) 930 ± 60 292 ± 23 79 ± 6 16.9 ± 1.4 3.9 ± 0.4 0.38 ± 0.08 SM+CI (Λ

⁻_LR

= 20 TeV) 910 ± 60 281 ± 23 61 ± 6 10.7 ± 1.1 1.76 ± 0.20 0.139 ± 0.029 SM + CI ( Λ

⁻_RR

= 14 TeV) 900 ± 60 285 ± 23 70 ± 6 13.8 ± 1.2 2.80 ± 0.32 0.20 ± 0.04 SM + CI ( Λ

⁻_RR

= 20 TeV) 870 ± 60 265 ± 23 58 ± 6 10.1 ± 1.1 1.29 ± 0.17 0.09 ± 0.02 SM + CI ( Λ

⁺_LL

= 14 TeV) 870 ± 60 252 ± 23 51 ± 6 7.5 ± 1.0 1.45 ± 0.18 0.113 ± 0.023 SM+CI (Λ

⁺_LL

= 20 TeV) 890 ± 60 247 ± 23 50 ± 6 6.4 ± 1.0 0.74 ± 0.15 0.048 ± 0.013 SM+CI (Λ

⁺_LR

= 14 TeV) 860 ± 60 256 ± 23 57 ± 6 12.2 ± 1.1 2.79 ± 0.31 0.28 ± 0.06 SM+CI (Λ

⁺_LR

= 20 TeV) 880 ± 60 252 ± 23 50 ± 6 7.5 ± 1.0 1.15 ± 0.16 0.092 ± 0.019 SM + CI ( Λ

⁺_RR

= 14 TeV) 870 ± 60 252 ± 23 51 ± 6 8.0 ± 1.0 1.36 ± 0.18 0.138 ± 0.026 SM + CI ( Λ

⁺_RR

= 20 TeV) 890 ± 60 247 ± 23 50 ± 6 6.5 ± 1.0 0.70 ± 0.15 0.052 ± 0.013

Events

10-1

1 10 102

103

104

105

106

107

Data 2012 γ* Z/

Photon-Induced Top quarks Multi-Jet & W+Jets Diboson

= 14 TeV

LL

Λ-

= 14 TeV

LL

Λ+

= 4.0 TeV (GRW) Ms

Preliminary ATLAS

L dt = 20.3 fb

-1

∫

ee:

= 8 TeV s

[TeV]

m

ee

0.1 0.2 0.3 0.4 1 2 3 4

Data / Bkg

^0.6

0.8 1 1.2

1.4

90 100 200 1000 2000

Events

10-1

1 10 102

103

104

105

106

107

Data 2012 γ* Z/

Photon-Induced Top quarks Diboson

= 14 TeV

LL

Λ-

= 14 TeV

LL

Λ+

= 4.0 TeV (GRW) MS

Preliminary ATLAS

L dt = 20.5 fb

-1

∫

µ : µ

= 8 TeV s

[TeV]

µ

m

µ

0.1 0.2 0.3 0.4 1 2 3 4

Data / Bkg

^0.6

0.8 1 1.2 1.4

Figure 1: Reconstructed dielectron (top) and dimuon (bottom) mass distributions for data and the SM background estimate. Also shown are the predictions for a benchmark Λ value in the LL contact interaction model and benchmark M S value in the GRW ADD model. The distribution bin width is constant in log(m ℓℓ ) and has the total systematic uncertainty overlaid as a band on the ratio.

7

Highest mass event ~ 1.9TeV

Z’ ruled out up to ~ 2.9TeV CI ruled out up to /\ ~ 26TeV

1 Introduction

Many theories beyond the Standard Model (SM) predict new phenomena which give rise to dilepton final states, such as new resonances. These have been searched for using the ATLAS detector and are reported elsewhere [1]. In this paper, a complementary search is performed for new phenomena that appear as broad deviations from the SM in the dilepton invariant mass distribution or in the angular distribution of the leptons (where the leptons considered in this analysis are electrons or muons). The phenomena under investigation are contact interactions (CI) and large extra dimensions (LED).

2 Theoretical Motivation

The presence of a new interaction can be detected at an energy much lower than that required to produce direct evidence of the existence of a new gauge boson. The charged weak interaction responsible for nuclear β decay provides such an example. A non-renormalizable description of this process was suc- cessfully formulated by Fermi in the form of a four-fermion contact interaction [2]. A contact interaction can also accommodate deviations in proton-proton scattering due to quark and lepton compositeness, where a characteristic energy scale Λ corresponds to the binding energy between fermion constituents.

A new interaction or compositeness in the process qq → ℓ + ℓ − can be described by the following four- fermion contact interaction Lagrangian [3, 4]:

L = g 2

Λ 2 [ η LL (q L γ µ q L ) ( ℓ L γ µ ℓ L ) + η RR (q R γ µ q R ) (ℓ R γ µ ℓ R ) + η LR (q L γ µ q L ) (ℓ R γ µ ℓ R ) + η RL (q R γ µ q R ) (ℓ L γ µ ℓ L ) ] ,

where g is a coupling constant chosen by convention to satisfy g 2 / 4 π = 1, Λ is the contact interaction scale, and q L , R and ℓ L , R are left-handed and right-handed quark and lepton fields, respectively. The parameters η i j , where i and j are L or R (left or right), define the chiral structure of the new interaction.

Di ﬀ erent chiral structures are investigated here, with the left-right model obtained by setting η LR = η RL = ± 1 and η LL = η RR = 0. Likewise, the left-left and right-right models are obtained by setting the corresponding parameters to ± 1, and the others to zero. The sign of η i j determines whether the interference is constructive ( η i j = − 1) or destructive ( η i j = + 1). The cross section for the process qq → ℓ + ℓ − in the presence of contact interactions can be written as:

σ tot = σ DY − η i j F I

Λ 2 + F C

Λ 4 , (1)

where the first term accounts for the qq → Z/γ ∗ → ℓ + ℓ − Drell-Yan (DY) process, the second term corresponds to the interference between the DY and CI processes, and the third term describes the pure CI process. These two latter terms include functions of the cross sections F I and F C , respectively, which do not depend on Λ . The relative impact of the interference and pure CI terms depends on both the dilepton mass and Λ . For example, the magnitude of the interference term for dilepton masses above 600 GeV is about twice as large as that of the pure CI term at Λ = 14 TeV; the interference becomes increasingly dominant for higher values of Λ .

A solution to the vast hierarchy between the electroweak (EW) and Planck scales has been proposed by Arkani-Hamed, Dimopoulos and Dvali (ADD) [5]. In this model, gravity is allowed to propagate in large flat extra spatial dimensions, thereby diluting its apparent e ﬀ ect in 3 + 1 spacetime dimensions.

The flat n extra dimensions are of common size R ( ∼ 1 µm – 1 mm, for n = 2) and compactified on an n- dimensional torus. The fundamental Planck scale in (4 + n)-dimensions, M D , is related to the Planck scale,

1

…

arXive:1405.4123 ATLAS-CONF-2014-030

e + e - µ + µ -

(16)

Singly produced Resonances

Final State Highest mass event

Highest mass limit

ee ~1.8TeV 2.79TeV

mumu ~1.8TeV 2.53TeV

tautau ~0.7TeV 1.9TeV dijet ~5.1TeV 5.1TeV

lnu ~2.4TeV 3.4TeV

bb ~4.1TeV ~1.2-1.5TeV

top b ~3.8TeV 2.05TeV ttbar * ~3.5TeV 1.8TeV

Highest mass limit WZ(3lnu) ~1.1TeV 1.5TeV VV(jjlnu) ~3.3TeV 2.5TeV Vq(jj) * ~3.7TeV 3.2TeV VV(jj) * ~2.7TeV 1.7TeV ZZ(lljj) ~1.7TeV 0.85TeV hh(4b) ~1.3TeV 590-710GeV

Wt ~1.8TeV 1.8TeV

γjet ~3TeV 3.5TeV

*Analysis is using jet-substructure techniques

Fermion Pairs Final states with bosons

Probing ~ 1 - 5 TeV scale masses

across a very wide range of final states

(17)

Pair produced Resonances

7/7/14 ICHEP 2014 17

Highest mass limit 2x(top jet) ~1.2TeV 0.8TeV 2x(bZ(ll)) >1TeV 0.7TeV 2x(jjj) ~1.9TeV 0.65TeV 2x(jjb) ~1.7TeV 0.835TeV 2x(top tau) S T ~ 0.8TeV 0.55TeV 2x(tau b) ~0.85TeV 0.74TeV 2x(mu jet) ~1.2TeV 1.07TeV

Probing 0.5 – 1 TeV scale physics across a wide

range of final states

single

pair

Model ℓ,γ Jets E^miss

T

!Ldt[fb⁻¹] Mass limit Reference

ExtradimensionsGaugebosonsCIDMLQHeavy quarksExcited fermionsOther

ADDGKK+g/q − 1-2 j Yes 4.7 MD 4.37 TeV n= 2 1210.4491

ADD non-resonantℓℓ 2e,µ − − 20.3 MS 5.2 TeV n= 3HLZ ATLAS-CONF-2014-030

ADD QBH→ℓq 1e,µ 1 j − 20.3 Mth 5.2 TeV n= 6 1311.2006

ADD QBH − 2 j − 20.3 Mth 5.82 TeV n= 6 to be submitted to PRD

ADD BH highNtrk 2µ(SS) − − 20.3 Mth 5.7 TeV n= 6,MD= 1.5TeV, non-rot BH 1308.4075

ADD BH high!pT ≥1e,µ ≥2j − 20.3 Mth 6.2 TeV n= 6,MD= 1.5TeV, non-rot BH 1405.4254

RS1GKK→ℓℓ 2e,µ − − 20.3 GKKmass 2.68 TeV k/MPl= 0.1 1405.4123

RS1GKK→WW→ℓνℓν 2e,µ − Yes 4.7 GKKmass 1.23 TeV k/MPl= 0.1 1208.2880

Bulk RSGKK→ZZ→ℓℓqq 2e,µ 2 j / 1 J − 20.3 GKKmass 730 GeV k/MPl= 1.0 ATLAS-CONF-2014-039

Bulk RSGKK→HH→b¯bb¯b − 4 b − 19.5 GKKmass 590-710 GeV k/MPl= 1.0 ATLAS-CONF-2014-005

Bulk RSgKK→tt 1e,µ ≥1b,≥1J/2j Yes 14.3 ^g^KK^mass 2.0 TeV BR = 0.925 ATLAS-CONF-2013-052

S¹/Z2ED 2e,µ − − 5.0 MKK≈R⁻¹ 4.71 TeV 1209.2535

UED 2γ − Yes 4.8 Compact. scaleR⁻¹ 1.41 TeV ATLAS-CONF-2012-072

SSMZ^′→ℓℓ 2e,µ − − 20.3 Z^′mass 2.9 TeV 1405.4123

SSMZ^′→ττ 2τ − − 19.5 Z^′mass 1.9 TeV ATLAS-CONF-2013-066

SSMW^′→ℓν 1e,µ − Yes 20.3 W^′mass 3.28 TeV ATLAS-CONF-2014-017

EGMW^′→WZ→ℓν ℓ^′ℓ^′ 3e,µ − Yes 20.3 W^′mass 1.52 TeV 1406.4456

EGMW^′→WZ→qqℓℓ 2e,µ 2 j / 1 J − 20.3 W^′mass 1.59 TeV ATLAS-CONF-2014-039

LRSMW_R^′→tb 1e,µ 2 b, 0-1 j Yes 14.3 W^′mass 1.84 TeV ATLAS-CONF-2013-050

LRSMW_R^′→tb 0e,µ ≥1b, 1 J − 20.3 W^′mass 1.77 TeV to be submitted to EPJC

CIqqqq − 2 j − 4.8 Λ 7.6 TeV η= +1 1210.1718

CIqqℓℓ 2e,µ − − 20.3 Λ 21.6 TeV ^ηLL=−1 ATLAS-CONF-2014-030

CIuutt 2e,µ(SS)≥1b,≥1j Yes 14.3 Λ 3.3 TeV |C|= 1 ATLAS-CONF-2013-051

EFT D5 operator (Dirac) 0e,µ 1-2 j Yes 10.5 M∗ 731 GeV at 90% CL form(χ)<80GeV ATLAS-CONF-2012-147

EFT D9 operator (Dirac) 0e,µ 1 J,≤1j Yes 20.3 M_∗ 2.4 TeV at 90% CL form(χ)<100GeV 1309.4017

Scalar LQ 1^stgen 2e ≥2j − 1.0 LQ mass 660 GeV β= 1 1112.4828

Scalar LQ 2^ndgen 2µ ≥2j − 1.0 LQ mass 685 GeV ^β= 1 1203.3172

Scalar LQ 3^rdgen 1e,µ, 1τ 1 b, 1 j − 4.7 LQ mass 534 GeV β= 1 1303.0526

Vector-like quarkTT→Ht+X 1e,µ ≥2b,≥4j Yes 14.3 Tmass 790 GeV T in (T,B) doublet ATLAS-CONF-2013-018

Vector-like quarkTT→Wb+X 1e,µ ≥1b,≥3j Yes 14.3 Tmass 670 GeV isospin singlet ATLAS-CONF-2013-060

Vector-like quarkTT→Zt+X 2/≥3e,µ ≥2/≥1 b − 20.3 Tmass 735 GeV T in (T,B) doublet ATLAS-CONF-2014-036

Vector-like quarkBB→Zb+X 2/≥3e,µ ≥2/≥1 b − 20.3 Bmass 755 GeV B in (B,Y) doublet ATLAS-CONF-2014-036

Vector-like quarkBB→Wt+X 2e,µ(SS)≥1b,≥1j Yes 14.3 Bmass 720 GeV B in (T,B) doublet ATLAS-CONF-2013-051

Excited quarkq^∗→qγ 1γ 1 j − 20.3 q^∗mass 3.5 TeV onlyu^∗andd^∗,Λ=m(q^∗) 1309.3230

Excited quarkq^∗→qg − 2 j − 20.3 q^∗mass 4.09 TeV onlyu^∗andd^∗,Λ=m(q^∗) to be submitted to PRD

Excited quarkb^∗→Wt 1 or 2e,µ1 b, 2 j or 1 j Yes 4.7 b^∗mass 870 GeV left-handed coupling 1301.1583

Excited leptonℓ^∗→ℓγ 2e,µ, 1γ − − 13.0 ℓ^∗mass 2.2 TeV Λ= 2.2TeV 1308.1364

LSTCaT→Wγ 1e,µ, 1γ − Yes 20.3 aTmass 960 GeV to be submitted to PLB

LRSM Majoranaν 2e,µ 2 j − 2.1 N⁰mass 1.5 TeV m(WR) = 2TeV, no mixing 1203.5420

Type III Seesaw 2e,µ − − 5.8 N^±mass 245 GeV |Ve|=0.055,|Vµ|=0.063,|Vτ|=0 ATLAS-CONF-2013-019

Higgs tripletH^±±→ℓℓ 2e,µ(SS) − − 4.7 H^±±mass 409 GeV DY production, BR(H^±±→ℓℓ)=1 1210.5070

Multi-charged particles − − − 4.4 multi-charged particle mass 490 GeV DY production,|q|= 4e 1301.5272

Magnetic monopoles − − − 2.0 monopole mass 862 GeV DY production,|g|= 1gD 1207.6411

Mass scale [TeV]

10⁻¹ 1 10

√s= 7 TeV √ s= 8 TeV

ATLAS Exotics Searches* - 95% CL Exclusion

Status: ICHEP 2014

ATLAS

Preliminary

"

Ldt= (1.0 - 20.3) fb⁻¹ √

s= 7, 8 TeV

*Only a selection of the available mass limits on new states or phenomena is shown.

Model ℓ,γ Jets E^miss

T

!Ldt[fb⁻¹] Mass limit Reference

ExtradimensionsGaugebosonsCIDMLQHeavy quarksExcited fermionsOther

ADDGKK+g/q − 1-2 j Yes 4.7 MD 4.37 TeV n= 2 1210.4491

ADD non-resonantℓℓ 2e,µ − − 20.3 MS 5.2 TeV n= 3HLZ ATLAS-CONF-2014-030

ADD QBH→ℓq 1e,µ 1 j − 20.3 Mth 5.2 TeV n= 6 1311.2006

ADD QBH − 2 j − 20.3 Mth 5.82 TeV n= 6 to be submitted to PRD

ADD BH highNtrk 2µ(SS) − − 20.3 Mth 5.7 TeV n= 6,MD= 1.5TeV, non-rot BH 1308.4075

ADD BH high!pT ≥1e,µ ≥2j − 20.3 Mth 6.2 TeV n= 6,MD= 1.5TeV, non-rot BH 1405.4254

RS1GKK→ℓℓ 2e,µ − − 20.3 GKKmass 2.68 TeV k/MPl= 0.1 1405.4123

RS1GKK→WW→ℓνℓν 2e,µ − Yes 4.7 GKKmass 1.23 TeV k/MPl= 0.1 1208.2880

Bulk RSGKK→ZZ→ℓℓqq 2e,µ 2 j / 1 J − 20.3 GKKmass 730 GeV k/MPl= 1.0 ATLAS-CONF-2014-039

Bulk RSGKK→HH→b¯bbb¯ − 4 b − 19.5 GKKmass 590-710 GeV k/MPl= 1.0 ATLAS-CONF-2014-005

Bulk RSgKK→tt 1e,µ ≥1b,≥1J/2j Yes 14.3 ^g^KK^mass 2.0 TeV BR = 0.925 ATLAS-CONF-2013-052

S¹/Z2ED 2e,µ − − 5.0 MKK≈R⁻¹ 4.71 TeV 1209.2535

UED 2γ − Yes 4.8 Compact. scaleR⁻¹ 1.41 TeV ATLAS-CONF-2012-072

SSMZ^′→ℓℓ 2e,µ − − 20.3 Z^′mass 2.9 TeV 1405.4123

SSMZ^′→ττ 2τ − − 19.5 Z^′mass 1.9 TeV ATLAS-CONF-2013-066

SSMW^′→ℓν 1e,µ − Yes 20.3 W^′mass 3.28 TeV ATLAS-CONF-2014-017

EGMW^′→WZ→ℓν ℓ^′ℓ^′ 3e,µ − Yes 20.3 W^′mass 1.52 TeV 1406.4456

EGMW^′→WZ→qqℓℓ 2e,µ 2 j / 1 J − 20.3 W^′mass 1.59 TeV ATLAS-CONF-2014-039

LRSMW_R^′→tb 1e,µ 2 b, 0-1 j Yes 14.3 W^′mass 1.84 TeV ATLAS-CONF-2013-050

LRSMW_R^′→tb 0e,µ ≥1b, 1 J − 20.3 W^′mass 1.77 TeV to be submitted to EPJC

CIqqqq − 2 j − 4.8 Λ 7.6 TeV η= +1 1210.1718

CIqqℓℓ 2e,µ − − 20.3 Λ 21.6 TeV ηLL=−1 ATLAS-CONF-2014-030

CIuutt 2e,µ(SS)≥1b,≥1j Yes 14.3 Λ 3.3 TeV |C|= 1 ATLAS-CONF-2013-051

EFT D5 operator (Dirac) 0e,µ 1-2 j Yes 10.5 M∗ 731 GeV at 90% CL form(χ)<80GeV ATLAS-CONF-2012-147

EFT D9 operator (Dirac) 0e,µ 1 J,≤1j Yes 20.3 M_∗ 2.4 TeV at 90% CL form(χ)<100GeV 1309.4017

Scalar LQ 1^stgen 2e ≥2j − 1.0 LQ mass 660 GeV β= 1 1112.4828

Scalar LQ 2^ndgen 2µ ≥2j − 1.0 LQ mass 685 GeV ^β= 1 1203.3172

Scalar LQ 3^rdgen 1e,µ, 1τ 1 b, 1 j − 4.7 LQ mass 534 GeV ^β= 1 1303.0526