exotic searches with atlas - cerncds.cern.ch/record/2030886/files/atl-phys-slide-2015-357.pdf ·...

Exotic Searches with ATLAS

Rebecca Falla on behalf of the ATLAS Collaboration

QFTHEP 2015 Samara, Russia

Motivation The Standard Model has been very successful but there are still problems Ø  Dark Matter Ø  Mass hierarchy problem Ø  Neutrino masses Ø  Gravity Ø  ……

Exotic theories could hold the answers to these questions Ø  Supersymmetry? Ø  Extra dimensions? Ø  WIMPS as dark matter candidates? Ø  Seesaw mechanism? Ø  New TeV scale interactions or particles? Ø  …..?

2

Model ℓ, γ Jets EmissT

∫L dt[fb−1] Mass limit Reference

Extra

dimensio

nsGauge

bosons

CIDM

LQHe

avy

quarks

Excited

fermions

Other

ADD GKK + g/q − ≥ 1 j Yes 20.3 n = 2 1502.015185.25 TeVMD

ADD non-resonant ℓℓ 2e,µ − − 20.3 n = 3 HLZ 1407.24104.7 TeVMS

ADD QBH→ ℓq 1 e,µ 1 j − 20.3 n = 6 1311.20065.2 TeVMth

ADD QBH − 2 j − 20.3 n = 6 1407.13765.82 TeVMth

ADD BH high Ntrk 2 µ (SS) − − 20.3 n = 6, MD = 3 TeV, non-rot BH 1308.40754.7 TeVMth

ADD BH high ∑ pT ≥ 1 e, µ ≥ 2 j − 20.3 n = 6, MD = 3 TeV, non-rot BH 1405.42545.8 TeVMth

ADD BH high multijet − ≥ 2 j − 20.3 n = 6, MD = 3 TeV, non-rot BH Preliminary5.8 TeVMth

RS1 GKK → ℓℓ 2 e,µ − − 20.3 k/MPl = 0.1 1405.41232.68 TeVGKK massRS1 GKK → γγ 2 γ − − 20.3 k/MPl = 0.1 Preliminary2.66 TeVGKK massBulk RS GKK → ZZ → qqℓℓ 2 e,µ 2 j / 1 J − 20.3 k/MPl = 1.0 1409.6190740 GeVGKK massBulk RS GKK →WW → qqℓν 1 e,µ 2 j / 1 J Yes 20.3 k/MPl = 1.0 1503.04677700 GeVW′ massBulk RS GKK → HH → bb̄bb̄ − 4 b − 19.5 k/MPl = 1.0 ATLAS-CONF-2014-005590-710 GeVGKK massBulk RS gKK → tt 1 e,µ ≥ 1 b, ≥ 1J/2j Yes 20.3 BR = 0.925 ATLAS-CONF-2015-0092.2 TeVgKK mass2UED / RPP 2 e,µ (SS) ≥ 1 b, ≥ 1 j Yes 20.3 Preliminary960 GeVKK mass

SSM Z ′ → ℓℓ 2 e,µ − − 20.3 1405.41232.9 TeVZ′ massSSM Z ′ → ττ 2 τ − − 19.5 1502.071772.02 TeVZ′ massSSM W ′ → ℓν 1 e,µ − Yes 20.3 1407.74943.24 TeVW′ massEGM W ′ →WZ → ℓν ℓ′ℓ′ 3 e,µ − Yes 20.3 1406.44561.52 TeVW′ massEGM W ′ →WZ → qqℓℓ 2 e,µ 2 j / 1 J − 20.3 1409.61901.59 TeVW′ massHVT W ′ →WH → ℓνbb 1 e,µ 2 b Yes 20.3 gV = 1 Preliminary1.47 TeVW′ massLRSM W ′

R → tb 1 e,µ 2 b, 0-1 j Yes 20.3 1410.41031.92 TeVW′ massLRSM W ′

R → tb 0 e,µ ≥ 1 b, 1 J − 20.3 1408.08861.76 TeVW′ mass

CI qqqq − 2 j − 17.3 ηLL = −1 Preliminary12.0 TeVΛ

CI qqℓℓ 2 e,µ − − 20.3 ηLL = −1 1407.241021.6 TeVΛ

CI uutt 2 e,µ (SS) ≥ 1 b, ≥ 1 j Yes 20.3 |CLL | = 1 Preliminary4.35 TeVΛ

EFT D5 operator (Dirac) 0 e,µ ≥ 1 j Yes 20.3 at 90% CL for m(χ) < 100 GeV 1502.01518974 GeVM∗EFT D9 operator (Dirac) 0 e,µ 1 J, ≤ 1 j Yes 20.3 at 90% CL for m(χ) < 100 GeV 1309.40172.4 TeVM∗

Scalar LQ 1st gen 2 e ≥ 2 j − 1.0 β = 1 1112.4828660 GeVLQ massScalar LQ 2nd gen 2 µ ≥ 2 j − 1.0 β = 1 1203.3172685 GeVLQ massScalar LQ 3rd gen 1 e, µ, 1 τ 1 b, 1 j − 4.7 β = 1 1303.0526534 GeVLQ mass

VLQ TT → Ht + X ,Wb + X 1 e,µ ≥ 1 b, ≥ 3 j Yes 20.3 isospin singlet ATLAS-CONF-2015-012785 GeVT massVLQ TT → Zt + X 2/≥3 e, µ ≥2/≥1 b − 20.3 T in (T,B) doublet 1409.5500735 GeVT massVLQ BB → Zb + X 2/≥3 e, µ ≥2/≥1 b − 20.3 B in (B,Y) doublet 1409.5500755 GeVB massVLQ BB →Wt + X 1 e,µ ≥ 1 b, ≥ 5 j Yes 20.3 isospin singlet Preliminary640 GeVB massT5/3 →Wt 1 e,µ ≥ 1 b, ≥ 5 j Yes 20.3 Preliminary840 GeVT5/3 mass

Excited quark q∗ → qγ 1 γ 1 j − 20.3 only u∗ and d ∗, Λ = m(q∗) 1309.32303.5 TeVq∗ massExcited quark q∗ → qg − 2 j − 20.3 only u∗ and d ∗, Λ = m(q∗) 1407.13764.09 TeVq∗ massExcited quark b∗ →Wt 1 or 2 e,µ 1 b, 2 j or 1 j Yes 4.7 left-handed coupling 1301.1583870 GeVb∗ massExcited lepton ℓ∗ → ℓγ 2 e, µ, 1 γ − − 13.0 Λ = 2.2 TeV 1308.13642.2 TeVℓ∗ massExcited lepton ν∗ → ℓW , νZ 3 e, µ, τ − − 20.3 Λ = 1.6 TeV 1411.29211.6 TeVν∗ mass

LSTC aT →W γ 1 e, µ, 1 γ − Yes 20.3 1407.8150960 GeVaT massLRSM Majorana ν 2 e,µ 2 j − 2.1 m(WR ) = 2 TeV, no mixing 1203.54201.5 TeVN0 massHiggs triplet H±± → ℓℓ 2 e,µ (SS) − − 20.3 DY production, BR(H±±L → ℓℓ)=1 1412.0237551 GeVH±± massHiggs triplet H±± → ℓτ 3 e, µ, τ − − 20.3 DY production, BR(H±±L → ℓτ)=1 1411.2921400 GeVH±± massMonotop (non-res prod) 1 e,µ 1 b Yes 20.3 anon−res = 0.2 1410.5404657 GeVspin-1 invisible particle massMulti-charged particles − − − 20.3 DY production, |q| = 5e Preliminary785 GeVmulti-charged particle massMagnetic monopoles − − − 2.0 DY production, |g | = 1gD 1207.6411862 GeVmonopole mass

Mass scale [TeV]10−1 1 10√s = 7 TeV

√s = 8 TeV

ATLAS Exotics Searches* - 95% CL ExclusionStatus: March 2015

ATLAS Preliminary∫L dt = (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.

3 From March 2015

Outline

I’ll be showing recent exotic search results from ATLAS:

Long Lived Particle Searches H→γγ + MET

VLQ in Lepton + jets H→Z(d)Zd→4l

Z + lepton HH→bbbb

tt resonances in lepton + jets Diboson resonances in boosted boson tagged jets

All results shown are from 2012 √s = 8 TeV data, made public in May and June 2015. There are many more results which can be found here

4

- - -

Long Lived Particle Searches Many new physics models give rise to new, massive particles with long lifetimes LLPs can arise in models with: Ø  Small coupling in decay chain Ø  Strong virtuality (decay to heavy particles) Ø  Small mass differences in decay chain Ø  Pair production of particles with conserved quantum numbers

These lead to signatures which we can look for: Ø  Non-pointing or delayed photons Ø  Out-of-time decays Ø  Lepton jets Ø  Large dE/dx Ø  Disappearing tracks Ø  Displaced jets/vertices Ø  Trackless jets Ø  … 5

Long Lived Particle Searches Summary

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[GeV]γγm110 120 130 140 150 160

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9DataTotalBest-fit BSM HiggsSM HiggsBackground fit

ATLAS-1 dt = 20.3 fbL∫ = 8 TeV, s

= 125.4 GeVHm, γγ →H , missTH + E

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Search for Dark Matter in H(→γγ) + MET

H

χ

χ

q, g

q, g

H, Z, γ,Z ′, S, ...

DM invisible to detector Ø  Uses H→γγ to tag and trigger Ø  Look for large MET and local excess of events

in mγγ spectrum near mH Main Cuts: 105 < mγγ < 160 GeV, MET > 90 GeV Backgrounds: Ø  SM Higgs bkgd from MC Ø  Continuum bkgds from mγγ sideband

arXiv:1506.01081

[GeV] miss TE

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+ diboson tt γγ → H SM γγW

γγZ Data

γγ + jets γ + X W/Z

+ diboson tt γγ → H SM γγW

γγZ Data

ATLAS

-1 = 20.3 fbt dL ∫ = 8 TeVs

[GeV]χm1 10 210 310

qC

oupl

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ATLAS-1 dt = 20.3 fb L∫ = 8 TeV s

γγ →H , miss T H + E

LUX

=1)χ

Monojet (g

=1 TeV Z' , mBZ'

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Search for Dark Matter in H(→γγ) + MET

[GeV]χm1 10 210 310

[GeV

]Λ

Mas

s sc

ale

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510ATLAS

-1 dt = 20.3 fb L∫ = 8 TeV sγγ →H , miss T H + E

)πNon-perturbative (g>4

inv)→BF(Z

LUX

H µ D+ Hχ µ∂ χ

No truncationπTrunc. g=4

Trunc. g=1

1.4σ excess observed relative to expected limit Ø  Observed (expected) upper limit on the σfid is 0.70 (0.43)

fb at 95% CL

arXiv:1506.01081

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= 8 TeVs, -120.3 fb

ATLAS

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[GeV]recom0 200 400 600 800 1000

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ata

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kg

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3 Analyses performed: TT→Wb + X, TT→Ht + X and tttt production, BB → Hb + X TT→Wb + X Ø  Reconstruct T mass using boosted W

bosons and b-tagged jets

9

Search for Vector Like Quark pairs and 4t in the lepton + jets final state

arXiv:1505.04306

T

T̄W−, H, Z

b̄, t̄, t̄

b

W+

g

g

VLQs cancel out quadratic divergences to the Higgs Boson mass Ø  Decays: T→Wb,Zt,Ht B→Wt,Zb,Hb

_ _ _

_ - -

T

T̄W−, H, Z

b̄, t̄, t̄

t

H

g

g

3 Analyses performed: TT→Wb + X, TT→Ht + X and tttt production, BB → Hb + X TT→Ht + X and tttt production Ø  Dominant decay is H→bb Ø  Focus on high jet & b-jet multiplicities Ø  Use HT as discriminant: Σ(jet pT, lepton pT, MET) Ø  Also used to set limits on 4t production in

several benchmark scenarios

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> 100 GeVR∆min

bb 6 j, 3 b, M≥

Post-fit

Ht+X

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Search for Vector Like Quark pairs and 4t in the lepton + jets final state VLQs cancel out quadratic divergences to the Higgs Boson mass Ø  Decays: T→Wb,Zt,Ht B→Wt,Zb,Hb

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_ - - _

arXiv:1505.04306

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> 100 GeVR∆min

bb 4 b, M≥ 6 j, ≥

Post-fit

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2 0

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B̄W+, H, Z

t̄, b̄, b̄

b

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g

g

3 Analyses performed: TT→Wb + X, TT→Ht + X and tttt production, BB → Hb + X

BB → Hb + X Ø  Same strategy as Ht + X but optimised for

B→Hb Ø  Look at BB→HbHb→(WW)b(bb)b where one

W decays leptonically

11

Search for Vector Like Quark pairs and 4t in the lepton + jets final state VLQs cancel out quadratic divergences to the Higgs Boson mass Ø  Decays: T→Wb,Zt,Ht B→Wt,Zb,Hb

_ _ _

_ - -

_ _ _ _

arXiv:1505.04306

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) [p

b]

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→(p

p

σ

ATLAS

Wb)=1→BR(T

Wb+X

-1 = 8 TeV, 20.3 fbs

)σ1±Theory (NNLO prediction

95% CL observed limit

95% CL expected limit

σ1±95% CL expected limit


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Wb)→BR(T

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ATLAS-1 = 8 TeV, 20.3 fbs Summary results:

Same-Sign dil.arXiv:1504.04605

Zb/t + XJHEP11(2014)104

Ht+X,Wb+X comb.arXiv:1505.04306

750

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Wt)→BR(B

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ATLAS-1 = 8 TeV, 20.3 fbs Summary results:

Same-Sign dil.arXiv:1504.04605

Zb/t + XJHEP11(2014)104

Wt+XarXiv:1503.05425

Hb+XarXiv:1505.04306

650

700

750

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Search for Vector Like Quark pairs and 4t in the lepton + jets final state

12

See also: Same-Sign dilepton, arXiv:1504.04605 Zb/t + X, JHEP11(2014)104 Wt + X, arXiv:1503.05425

arXiv:1505.04306

Search for new light gauge bosons in H→Z(d)Zd→4l

13

arXiv:1505.07645

The presence of a dark sector which couples to the SM can be inferred from exotic intermediate decays of Higgs Bosons Ø  Looking for H→ZZd/ZdZd→4l (l = e/µ) H→ZZd→4l: Ø  Define m12 as invariant mass of

opp. Sign, same flavour lepton pair with m closest to Z boson

Ø  m34 is invariant mass of remaining pair

Ø  Look for local excess in m34

[GeV]dZm

15 20 25 30 35 40 45 50 55

B95

% C

L up

per l

imit

on R

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σ 1 ±σ 2 ±

ATLAS-1=8 TeV, 20.7 fbs

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8ATLAS

-1=8 TeV, 20.7 fbs

=125 GeVHm

4l→ ZZ* →H 4l→ZZ*

tZ+jets, tData 2012

RB =BR(H→ ZZd → 4l)

BR(H→ 4l)

Search for new light gauge bosons in H→Z(d)Zd→4l

14

The presence of a dark sector which couples to the SM can be inferred from exotic intermediate decays of Higgs Bosons Ø  Looking for H→ZZd/ZdZd→4l (l = e/µ)

H→ZdZd→4l: Ø  Events are selected by requiring the

difference in invariant mass of the dilepton pairs is minimized

Ø  Upper limits are computed from a maximum likelihood fit

[GeV]dZm

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dµ95

% C

L U

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Bou

nd o

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ObservedExpected

σ 1 ±σ 2 ±

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µ+4µFinal State: 4e+2e2

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Data 2012ZZ* -> 4lH->ZZ*->4lWW,WZtt

Zbb, Z+jets(Z+) quarkoniumTotal background

ATLAS-1 = 8 TeV, 20.3 fbs

= 125 GeVHm

m| [GeV]∆|0 5 10 15 20 25 30 35 40 45 50Si

gnifi

canc

e

4−2−024

µd =σ ×BR(H→ ZdZd → 4l)[σ ×BR(H→ ZZ*→ 4l)]SM

arXiv:1505.07645

Search for heavy lepton resonances in Z + lepton events

15

q

q

Z/γ∗L+

L−

Zl+

l−

l+

ν, l−, l−

W−, Z,H

Many extensions to the SM predict heavy resonances in trileptons Ø  Seesaw Ø  Vector Like Leptons Searching for heavy leptons, L+,L-,N0 which decay to W/Z/H + l/ν (depending on charge)

Looking in L → l+Z(ll) channel Look for 3 leptons with 1 Z candidate, reconstruct mL from invariant mass of the 3 leptons and use ΔM ≡ m3l – mZ as discriminating variable Use 6 signal regions depending on 3rd lepton flavour and other side of event: 4l, 3l+jj, 3l-only Backgrounds: WZ, ZZ and DY Z+γ taken from MC. Other bkgds are constrained from scaling control samples in data

arXiv:1506.01291

Search for heavy lepton resonances in Z + lepton events

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Dataν lll→WZ

4l→ZZ+VttγZ+

Reducible*VVV

VLL, 140 GeVSeesaw, 300 GeV

-1=8 TeV, 20.3 fbs3l+jj SR, Z+e

ATLAS

[GeV]±Lm100 150 200 250 300

[fb]

σ95

% C

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mit

on

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ObservedTheor. Cross Section

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[GeV]±Lm100 200 300 400 500

[pb]

σ95

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Expectedσ1±σ2±

ObservedTheor. Cross Section

arXiv:1506.01291

Boosted Methods

boost

Example: X→hh→bbbb

17

Low h pT (low mX)

High h pT (high mX)

Rule of thumb for angular separation between decay products:

ΔR ≈ 2mpT

h h

b

b

b b

X hhb

b

b

b_ _

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Higgs Boson Pair Production in the bbbb Final State

[GeV]KKG*m

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epta

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x Ef

ficie

ncy

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0.2 = 1.0PlMBulk RS, k/Resolved Analysis Boosted Analysis

= 8 TeVs

4 b-tagged jetsSignal Region

4 b-tagged jetsSignal Region ATLAS Simulation

arXiv:1506.00285

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New physics models predict enhanced Higgs Boson pair production rates over the SM

Boosted Higgs gives clear event topology Large BR(H→bb) means that the 4b final state happens ~⅓ of the time

Analysis based on two complementary approaches – resolved and boosted

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Higgs Boson Pair Production in the bbbb Final State

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3× = 1.0, PlMG*(1000), k/

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DataMultijettt

Syst+Stat Uncertainty 2× = 1.0, PlMG*(1000), k/ 15× = 1.0, PlMG*(1500), k/

ATLAS = 8 TeVs

-1Ldt = 19.5 fb∫

[GeV]KKG*m

600 800 1000 1200 1400 1600 1800 2000

) [fb

]bbb

b→

hh

→ KK

G*

→(p

p σ

1

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= 1.0PlMBulk RS, k/Observed Limit (95% CL)Expected Limit (95% CL)

σ1±Expected σ2±Expected

ATLAS-1 Ldt = 19.5 fb∫ = 8 TeV s

k/ ¯MPl 95% CL Excluded G⇤KK Mass Range [GeV]

1.0 500� 720

1.5 500� 800 and 870� 910

2.0 500� 990

Upper limit on SM hh non-resonant production,

σ(pp→hh→bbbb) = 202 fb (95% CL) [SM prediction of 3.6 ± 0.5 fb]

World’s best limit!!

_ _

_ _

arXiv:1506.00285

tt Resonances using lepton + jet events arXiv:1505.07018

Lepton + jets final state has large BR & also good background discrimination Analysis based on two approaches “resolved” and “boosted”. If event fails boosted try resolved. Ø  Resolved: 1 lepton, ≥ 4 small radius jets, ≥ 1

b-tagged jet, MET > 20 GeV, MET + mT > 60 GeV

Ø  Boosted: same as resolved but require a trimmed Anti-KT 1.0 jet pT > 300 GeV, m > 100 GeV

No excesses found so limits on masses and cross-sections were made Ø  Observed limits exclude mZ’ < 1.8 TeV and

mgKK < 2.2 TeV

Z’ mass [TeV]0.5 1 1.5 2 2.5 3

) [pb

]t t

→ B

R(Z

’×

Z’σ

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310Obs. 95% CL upper limitExp. 95% CL upper limit

uncertaintyσExp. 1 uncertaintyσExp. 2

Leptophobic Z’(1.2%) (LO x 1.3)Leptophobic Z’(2%) (LO x 1.3)Leptophobic Z’(3%) (LO x 1.3)

Obs. 95% CL upper limitExp. 95% CL upper limit

uncertaintyσExp. 1 uncertaintyσExp. 2

Leptophobic Z’(1.2%) (LO x 1.3)Leptophobic Z’(2%) (LO x 1.3)Leptophobic Z’(3%) (LO x 1.3)


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2.0 TeV, 15.3%KK

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KKg


l+jets

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Many extensions to the SM predict heavy resonances with large BR to top-pairs

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High Mass Diboson Resonances with Boson-Tagged Jets

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arXiv:1506.00962

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0.2

0.25ATLAS Simulation

= 8 TeVs = 1.8 TeV)

W' WZ (m→EGM W'

Pythia QCD dijet

| < 1.2jj

y∆|| < 2

jη|

< 1.98 TeVjj m≤1.62 < 110 GeVj m≤60

> 0.45 y

[TeV]jm0 0.05 0.1 0.15 0.2 0.25 0.3 0.35

Frac

tion

of je

ts /

5.0

GeV

00.020.040.060.08

0.10.120.140.160.180.2

0.22 ATLAS Simulation = 8 TeVs

= 1.8 TeV)G

WW (m→ RSbulk G

= 1.8 TeV)G

ZZ (m→ RSbulk G

Pythia QCD dijet

| < 1.2jj

y∆|| < 2

jη|

< 1.98 TeVjj m≤1.62 > 0.45y

Many extensions to the SM predict high mass resonances in dibosons Ø  Bulk-RS graviton → WW/ZZ Ø  Extended gauge model: W’ →WZ All hadronic final state has large BR compared to leptonic and semileptonic decays

Boosted boson tagging to suppress backgrounds Ø  2 C/A 1.2 jets with m2J > 1.05 TeV Ø  √y ≥ 0.45, ntrack < 30, |mj - mV| < 13 GeV

Search for bumps on steeply falling background Ø  Background taken from fit to data Ø  Signal shape from MC


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WZ Selection

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Sign

ifica

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2−1−0123

[TeV]W' m1.4 1.6 1.8 2 2.2 2.4 2.6 2.8 3

WZ)

[fb]

→ B

R(W

' ×

W')

→(p

p σ

1−10

1

10

210

310

410 Observed 95% CL

Expected 95% CL

uncertaintyσ 1±

unceirtaintyσ 2±

EGM W', c = 1


[GeV]jjm1400 1600 1800 2000 2200 2400 2600 2800 3000

0Lo

cal p

4−10

3−10

2−10

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1

10WZ Selection

WW Selection

ZZ Selection

ATLAS-1=8TeV, 20.3 fbs

σ0 σ1

σ2

σ3

σ3.5

σ4

22

Most significant discrepancy from

background is in WZ selection at 2 TeV:

3.4σ local, 2.5σ global

EGM W’ excluded for 1.3 < mW’ < 1.5 TeV

arXiv:1506.00962


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< 60 GeVj1,j240 < m < 140 GeVj2,j1110 < m

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< 140 GeVj110 < m

[TeV]jjm1.5 2 2.5 3 3.5

Sign

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2−024

Checked for mistakes, bugs and shaping effects in Ø  Detector/data taking Ø  Jet reconstruction Ø  Event selection

arXiv:1506.00962

Summary Many exotic searches have been performed on the Run-1 data with ATLAS I’ve presented here 7 of them, but many more can be found at ExoticsPublicResults Many limits have been placed on models With the large increase in energy for Run 2, new physics may be just around the corner!!

24

Model ℓ, γ Jets EmissT

∫L dt[fb−1] Mass limit Reference

Extra

dimensio

nsGauge

bosons

CIDM

LQHe

avy

quarks

Excited

fermions

Other

ADD GKK + g/q − ≥ 1 j Yes 20.3 n = 2 1502.015185.25 TeVMD

ADD non-resonant ℓℓ 2e,µ − − 20.3 n = 3 HLZ 1407.24104.7 TeVMS

ADD QBH→ ℓq 1 e,µ 1 j − 20.3 n = 6 1311.20065.2 TeVMth

ADD QBH − 2 j − 20.3 n = 6 1407.13765.82 TeVMth

ADD BH high Ntrk 2 µ (SS) − − 20.3 n = 6, MD = 3 TeV, non-rot BH 1308.40754.7 TeVMth

ADD BH high ∑ pT ≥ 1 e, µ ≥ 2 j − 20.3 n = 6, MD = 3 TeV, non-rot BH 1405.42545.8 TeVMth

ADD BH high multijet − ≥ 2 j − 20.3 n = 6, MD = 3 TeV, non-rot BH Preliminary5.8 TeVMth

RS1 GKK → ℓℓ 2 e,µ − − 20.3 k/MPl = 0.1 1405.41232.68 TeVGKK massRS1 GKK → γγ 2 γ − − 20.3 k/MPl = 0.1 Preliminary2.66 TeVGKK massBulk RS GKK → ZZ → qqℓℓ 2 e,µ 2 j / 1 J − 20.3 k/MPl = 1.0 1409.6190740 GeVGKK massBulk RS GKK →WW → qqℓν 1 e,µ 2 j / 1 J Yes 20.3 k/MPl = 1.0 1503.04677700 GeVW′ massBulk RS GKK → HH → bb̄bb̄ − 4 b − 19.5 k/MPl = 1.0 ATLAS-CONF-2014-005590-710 GeVGKK massBulk RS gKK → tt 1 e,µ ≥ 1 b, ≥ 1J/2j Yes 20.3 BR = 0.925 ATLAS-CONF-2015-0092.2 TeVgKK mass2UED / RPP 2 e,µ (SS) ≥ 1 b, ≥ 1 j Yes 20.3 Preliminary960 GeVKK mass

SSM Z ′ → ℓℓ 2 e,µ − − 20.3 1405.41232.9 TeVZ′ massSSM Z ′ → ττ 2 τ − − 19.5 1502.071772.02 TeVZ′ massSSM W ′ → ℓν 1 e,µ − Yes 20.3 1407.74943.24 TeVW′ massEGM W ′ →WZ → ℓν ℓ′ℓ′ 3 e,µ − Yes 20.3 1406.44561.52 TeVW′ massEGM W ′ →WZ → qqℓℓ 2 e,µ 2 j / 1 J − 20.3 1409.61901.59 TeVW′ massHVT W ′ →WH → ℓνbb 1 e,µ 2 b Yes 20.3 gV = 1 Preliminary1.47 TeVW′ massLRSM W ′

R → tb 1 e,µ 2 b, 0-1 j Yes 20.3 1410.41031.92 TeVW′ massLRSM W ′

R → tb 0 e,µ ≥ 1 b, 1 J − 20.3 1408.08861.76 TeVW′ mass

CI qqqq − 2 j − 17.3 ηLL = −1 Preliminary12.0 TeVΛ

CI qqℓℓ 2 e,µ − − 20.3 ηLL = −1 1407.241021.6 TeVΛ

CI uutt 2 e,µ (SS) ≥ 1 b, ≥ 1 j Yes 20.3 |CLL | = 1 Preliminary4.35 TeVΛ

EFT D5 operator (Dirac) 0 e,µ ≥ 1 j Yes 20.3 at 90% CL for m(χ) < 100 GeV 1502.01518974 GeVM∗EFT D9 operator (Dirac) 0 e,µ 1 J, ≤ 1 j Yes 20.3 at 90% CL for m(χ) < 100 GeV 1309.40172.4 TeVM∗

Scalar LQ 1st gen 2 e ≥ 2 j − 1.0 β = 1 1112.4828660 GeVLQ massScalar LQ 2nd gen 2 µ ≥ 2 j − 1.0 β = 1 1203.3172685 GeVLQ massScalar LQ 3rd gen 1 e, µ, 1 τ 1 b, 1 j − 4.7 β = 1 1303.0526534 GeVLQ mass

VLQ TT → Ht + X ,Wb + X 1 e,µ ≥ 1 b, ≥ 3 j Yes 20.3 isospin singlet ATLAS-CONF-2015-012785 GeVT massVLQ TT → Zt + X 2/≥3 e, µ ≥2/≥1 b − 20.3 T in (T,B) doublet 1409.5500735 GeVT massVLQ BB → Zb + X 2/≥3 e, µ ≥2/≥1 b − 20.3 B in (B,Y) doublet 1409.5500755 GeVB massVLQ BB →Wt + X 1 e,µ ≥ 1 b, ≥ 5 j Yes 20.3 isospin singlet Preliminary640 GeVB massT5/3 →Wt 1 e,µ ≥ 1 b, ≥ 5 j Yes 20.3 Preliminary840 GeVT5/3 mass

Excited quark q∗ → qγ 1 γ 1 j − 20.3 only u∗ and d ∗, Λ = m(q∗) 1309.32303.5 TeVq∗ massExcited quark q∗ → qg − 2 j − 20.3 only u∗ and d ∗, Λ = m(q∗) 1407.13764.09 TeVq∗ massExcited quark b∗ →Wt 1 or 2 e,µ 1 b, 2 j or 1 j Yes 4.7 left-handed coupling 1301.1583870 GeVb∗ massExcited lepton ℓ∗ → ℓγ 2 e, µ, 1 γ − − 13.0 Λ = 2.2 TeV 1308.13642.2 TeVℓ∗ massExcited lepton ν∗ → ℓW , νZ 3 e, µ, τ − − 20.3 Λ = 1.6 TeV 1411.29211.6 TeVν∗ mass

LSTC aT →W γ 1 e, µ, 1 γ − Yes 20.3 1407.8150960 GeVaT massLRSM Majorana ν 2 e,µ 2 j − 2.1 m(WR ) = 2 TeV, no mixing 1203.54201.5 TeVN0 massHiggs triplet H±± → ℓℓ 2 e,µ (SS) − − 20.3 DY production, BR(H±±L → ℓℓ)=1 1412.0237551 GeVH±± massHiggs triplet H±± → ℓτ 3 e, µ, τ − − 20.3 DY production, BR(H±±L → ℓτ)=1 1411.2921400 GeVH±± massMonotop (non-res prod) 1 e,µ 1 b Yes 20.3 anon−res = 0.2 1410.5404657 GeVspin-1 invisible particle massMulti-charged particles − − − 20.3 DY production, |q| = 5e Preliminary785 GeVmulti-charged particle massMagnetic monopoles − − − 2.0 DY production, |g | = 1gD 1207.6411862 GeVmonopole mass

Mass scale [TeV]10−1 1 10√s = 7 TeV

√s = 8 TeV

ATLAS Exotics Searches* - 95% CL ExclusionStatus: March 2015

ATLAS Preliminary∫L dt = (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.

25 Thanks for Listening!

EXTRA SLIDES

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27


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Significance (stat)Significance (stat + syst)


WW Selection

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arXiv:1506.00962

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[TeV]RSG m

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WW

) [fb

]→

RS

BR

(G×)

RS

G→

(pp

σ

1−10

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Expected 95% CL

uncertaintyσ 1±

uncertaintyσ 2±

= 1PIM k/RSBulk G


[TeV]RSG m

1.4 1.6 1.8 2 2.2 2.4 2.6 2.8 3

ZZ)

[fb]

→ R

S B

R(G

×) R

S G

→(p

p σ

1−10

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Expected 95% CL

uncertaintyσ 1±

uncertaintyσ 2±

= 1PIM k/RSBulk G


arXiv:1506.00962

29


Parametric fit to background: dndx

= p1(1− x)p2−ξ p3 x p3

Where: Ø  X = mJJ/√s Ø  p1 is a normalisation factor Ø  p2 and p3 are dimensionless shape parameters Ø  ξ is a dimensionless constant chosen after the fitting to minimize the correlations

between p1 and p2

arXiv:1506.00962

High Mass Diboson Resonances with Boson-Tagged Jets Cross Checks

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jonly m

[TeV]jjm1.5 2 2.5 3 3.5

Sign

ifica

nce

2−1−0123


e.g. Ø  look at the effect

of single cuts on the distribution

Ø  Look at the effect of N-1 cuts on the distribution

arXiv:1506.00962

High Mass Diboson Resonances with Boson-Tagged Jets Cross Checks

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WZ Selection

[TeV]jjm1.5 2 2.5 3 3.5

Sign

ifica

nce

2−1−0123


e.g. Ø  look at the effect of

single cuts on the distribution

Ø  Look at the effect of N-1 cuts on the distribution

arXiv:1506.00962

32

High Mass Diboson Resonances with Boson-Tagged Jets – Similar Analyses

Pres

cale

-wei

ghte

d ev

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910

[dat

a-fit

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[TeV]jjReconstructed m0.3 0.4 0.5 1 2 3 4 5

Sign

if.

-202

ATLAS-1L dt=20.3 fb∫=8 TeV, s

DataFit

*, m = 0.6 TeVq*, m = 2.0 TeVq*, m = 3.5 TeVq

Even

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ATLAS-1 Ldt = 20.3 fb∫ = 8 TeV, s

1 large-R jet≥ + ν l→W

DataW/Z+jets

+single topttMultijetDibosonUncertaintyG*(1200 GeV)W'(1200 GeV)

[GeV]lvJm800 1000 1200 1400 1600 1800 2000 2200 2400D

ata

/ Bkg

00.5

11.5

2

arXiv:1506.00962

ATLAS resolved dijet search arXiv:1407.1376

ATLAS semileptonic search W(lν)Z(jj) arXiv:1503.04677

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ATLAS = 8 TeVs

-1L dt = 20.3 fb∫ Res. Region

THigh-p

Channelµµ ee, →Z

[GeV]lljjm0 500 1000 1500 2000 2500

Dat

a / B

G

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11.21.4

Dijet mass (GeV)1000150020002500300035004000450050005500

(pb/

GeV

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Prob 0.912p0 4.954e-10± 1.375e-08

p1 0.1057± 2.466 p2 0.01738± 8.023

p3 0.006963± 0.4947

/ ndf 2χ

24.32 / 35

Prob 0.912p0 4.954e-10± 1.375e-08

p1 0.1057± 2.466 p2 0.01738± 8.023

p3 0.006963± 0.4947

/ ndf 2χ

24.32 / 35

Prob 0.912p0 4.954e-10± 1.375e-08

p1 0.1057± 2.466 p2 0.01738± 8.023

p3 0.006963± 0.4947

DataFit

CMS (8 TeV) -119.7 fb

b* (1.8 TeV) Z' (2.2 TeV)

G (2.8 TeV)

Z' (3.2 TeV)

2 b tags

Wide jets (R = 1.1)

| < 1.3jjη∆| < 2.5 & | η|

Dijet mass (GeV)1000 2000 3000 4000 5000

Res

idua

ls

-2

0

2

arXiv:1506.00962

ATLAS semileptonic search W(jj)Z(ll) arXiv:1409.6190

CMS dijet search arXiv:1501.04198

Phys. Rev. D 91, 052009 (2015)

Tiny blip at 2 TeV in 2 b-tag channel

34


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Other (151) = 2.5 TeV (29)RWM

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= 2.5 TeV unbinnedRWM

(8 TeV)-119.7 fb

CMS

[TeV]eejjM0 1 2 3 4

Dat

a/SM

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No Shape Uncertainty

[GeV]ZZm500 1000 1500 2000 2500

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10CMS Data (ee HP)Background estimationZ+jets

, VV)tOther Backgrounds (t = 0.5 (x100)PlM/k = 1 TeV, G MbulkG

= 8 TeVs at -1CMS L = 19.7 fb

arXiv:1506.00962

CMS right-handed boson search arXiv:1407.3683

Eur. Phys. J. C 74 (2014) 3149

CMS semileptonic WW WZ ZZ search arXiv:1405.3447

JHEP 08 (2014) 174

Excess at 2 TeV only seen in eejj channel

35


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Fit WW (1.5 TeV)→ RSG

= 8 TeVs, -1CMS, L = 19.7 fb

(TeV)jjm1 1.5 2 2.5 3

Data

σ

Da

ta-F

it

-202

arXiv:1506.00962

CMS fully hadronic WW WZ ZZ search arXiv:1405.1994

JHEP 08 (2014) 173

Broad blip at 2 TeV

exotic searches with atlas - cerncds.cern.ch/record/2030886/files/atl-phys-slide-2015-357.pdf ·...

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