ATLAS results on searches for exotic particles - cds.cern.ch fileIntroduction L Many BSM theories:...
Transcript of ATLAS results on searches for exotic particles - cds.cern.ch fileIntroduction L Many BSM theories:...
ATLAS results onsearches for exotic new particles
Sara Alderweireldton behalf of the ATLAS Collaboration
Aspen 2018 – The Particle FrontierAspen, CO
March 28, 2018
Introduction Many BSM theories:
∎ Grand Unification Theory∎ Sequential Standard Model∎ Dark sector extensions∎ Two-Higgs-doublet model
Many final states and many regions of phase space to consider∎ Search for any deviation from the SM prediction
Pushing limits both at high and low mass
2015+2016 dataset: 36.1 fb−1
∎ Triplets∎ Extra dimensions∎ Gravitons∎ . . .
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ATLAS Online Luminosity = 7 TeVs2011 pp
= 8 TeVs2012 pp
= 13 TeVs2015 pp
= 13 TeVs2016 pp
= 13 TeVs2017 pp
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8 c
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Model ℓ, γ Jets† EmissT
∫L dt[fb−1] Limit Reference
Ext
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Exc
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Oth
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ADD GKK + g/q 0 e, µ 1 − 4 j Yes 36.1 n = 2 ATLAS-CONF-2017-0607.75 TeVMD
ADD non-resonant γγ 2 γ − − 36.7 n = 3 HLZ NLO CERN-EP-2017-1328.6 TeVMS
ADD QBH − 2 j − 37.0 n = 6 1703.092178.9 TeVMth
ADD BH high∑pT ≥ 1 e, µ ≥ 2 j − 3.2 n = 6, MD = 3 TeV, rot BH 1606.022658.2 TeVMth
ADD BH multijet − ≥ 3 j − 3.6 n = 6, MD = 3 TeV, rot BH 1512.025869.55 TeVMth
RS1 GKK → γγ 2 γ − − 36.7 k/MPl = 0.1 CERN-EP-2017-1324.1 TeVGKK mass
Bulk RS GKK →WW → qqℓν 1 e, µ 1 J Yes 36.1 k/MPl = 1.0 ATLAS-CONF-2017-0511.75 TeVGKK mass
2UED / RPP 1 e, µ ≥ 2 b, ≥ 3 j Yes 13.2 Tier (1,1), B(A(1,1) → tt) = 1 ATLAS-CONF-2016-1041.6 TeVKK mass
SSM Z ′ → ℓℓ 2 e, µ − − 36.1 ATLAS-CONF-2017-0274.5 TeVZ′ mass
SSM Z ′ → ττ 2 τ − − 36.1 ATLAS-CONF-2017-0502.4 TeVZ′ massLeptophobic Z ′ → bb − 2 b − 3.2 1603.087911.5 TeVZ′ massLeptophobic Z ′ → tt 1 e, µ ≥ 1 b, ≥ 1J/2j Yes 3.2 Γ/m = 3% ATLAS-CONF-2016-0142.0 TeVZ′ mass
SSM W ′ → ℓν 1 e, µ − Yes 36.1 1706.047865.1 TeVW′ massHVT V ′ →WV → qqqq model B 0 e, µ 2 J − 36.7 gV = 3 CERN-EP-2017-1473.5 TeVV′ massHVT V ′ →WH/ZH model B multi-channel 36.1 gV = 3 ATLAS-CONF-2017-0552.93 TeVV′ 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 − 37.0 η−LL 1703.0921721.8 TeVΛ
CI ℓℓqq 2 e, µ − − 36.1 η−LL ATLAS-CONF-2017-02740.1 TeVΛ
CI uutt 2(SS)/≥3 e,µ ≥1 b, ≥1 j Yes 20.3 |CRR | = 1 1504.046054.9 TeVΛ
Axial-vector mediator (Dirac DM) 0 e, µ 1 − 4 j Yes 36.1 gq=0.25, gχ=1.0, m(χ) < 400 GeV ATLAS-CONF-2017-0601.5 TeVmmed
Vector mediator (Dirac DM) 0 e, µ, 1 γ ≤ 1 j Yes 36.1 gq=0.25, gχ=1.0, m(χ) < 480 GeV 1704.038481.2 TeVmmed
VVχχ EFT (Dirac DM) 0 e, µ 1 J, ≤ 1 j Yes 3.2 m(χ) < 150 GeV 1608.02372700 GeVM∗
Scalar LQ 1st gen 2 e ≥ 2 j − 3.2 β = 1 1605.060351.1 TeVLQ mass
Scalar LQ 2nd gen 2 µ ≥ 2 j − 3.2 β = 1 1605.060351.05 TeVLQ mass
Scalar LQ 3rd gen 1 e, µ ≥1 b, ≥3 j Yes 20.3 β = 0 1508.04735640 GeVLQ mass
VLQ TT → Ht + X 0 or 1 e, µ ≥ 2 b, ≥ 3 j Yes 13.2 B(T → Ht) = 1 ATLAS-CONF-2016-1041.2 TeVT mass
VLQ TT → Zt + X 1 e, µ ≥ 1 b, ≥ 3 j Yes 36.1 B(T → Zt) = 1 1705.107511.16 TeVT mass
VLQ TT →Wb + X 1 e, µ ≥ 1 b, ≥ 1J/2j Yes 36.1 B(T →Wb) = 1 CERN-EP-2017-0941.35 TeVT mass
VLQ BB → Hb + X 1 e, µ ≥ 2 b, ≥ 3 j Yes 20.3 B(B → Hb) = 1 1505.04306700 GeVB mass
VLQ BB → Zb + X 2/≥3 e, µ ≥2/≥1 b − 20.3 B(B → Zb) = 1 1409.5500790 GeVB mass
VLQ BB →Wt + X 1 e, µ ≥ 1 b, ≥ 1J/2j Yes 36.1 B(B →Wt) = 1 CERN-EP-2017-0941.25 TeVB massVLQ QQ →WqWq 1 e, µ ≥ 4 j Yes 20.3 1509.04261690 GeVQ mass
Excited quark q∗ → qg − 2 j − 37.0 only u∗ and d∗, Λ = m(q∗) 1703.091276.0 TeVq∗ mass
Excited quark q∗ → qγ 1 γ 1 j − 36.7 only u∗ and d∗, Λ = m(q∗) CERN-EP-2017-1485.3 TeVq∗ mass
Excited quark b∗ → bg − 1 b, 1 j − 13.3 ATLAS-CONF-2016-0602.3 TeVb∗ massExcited quark b∗ →Wt 1 or 2 e, µ 1 b, 2-0 j Yes 20.3 fg = fL = fR = 1 1510.026641.5 TeVb∗ massExcited lepton ℓ∗ 3 e, µ − − 20.3 Λ = 3.0 TeV 1411.29213.0 TeVℓ∗ massExcited lepton ν∗ 3 e,µ, τ − − 20.3 Λ = 1.6 TeV 1411.29211.6 TeVν∗ mass
LRSM Majorana ν 2 e, µ 2 j − 20.3 m(WR ) = 2.4 TeV, no mixing 1506.060202.0 TeVN0 massHiggs triplet H±± → ℓℓ 2,3,4 e,µ (SS) − − 36.1 DY production ATLAS-CONF-2017-053870 GeVH±± massHiggs triplet H±± → ℓτ 3 e,µ, τ − − 20.3 DY production, B(H±±
L→ ℓτ) = 1 1411.2921400 GeVH±± mass
Monotop (non-res prod) 1 e, µ 1 b Yes 20.3 anon−res = 0.2 1410.5404657 GeVspin-1 invisible particle mass
Multi-charged particles − − − 20.3 DY production, |q| = 5e 1504.04188785 GeVmulti-charged particle mass
Magnetic monopoles − − − 7.0 DY production, |g | = 1gD , spin 1/2 1509.080591.34 TeVmonopole mass
Mass scale [TeV]10−1 1 10√s = 8 TeV
√s = 13 TeV
ATLAS Exotics Searches* - 95% CL Upper Exclusion LimitsStatus: July 2017
ATLAS Preliminary∫L dt = (3.2 – 37.0) fb−1
√s = 8, 13 TeV
*Only a selection of the available mass limits on new states or phenomena is shown.†Small-radius (large-radius) jets are denoted by the letter j (J).
Mediator Mass [TeV]
0 0.5 1 1.5 2 2.5 3
DM
Mas
s [T
eV]
0.2
0.4
0.6
0.8
1
1.2DM Simplified Model Exclusions Preliminary July 2017ATLAS
= 1DM
= 0, gl
= 0.25, gq
gAxial-vector mediator, Dirac DM
All limits at 95% CL
Per
turb
ativ
e U
nita
rity
Dije
t
arXiv:1703.09127 [hep-ex]
-1 = 13 TeV, 37.0 fbs
Dijet
Dije
t 8 T
eV
Phys. Rev. D. 91 052007 (2015)
-1 = 8 TeV, 20.3 fbs
Dijet 8 TeV
Dije
t TLA
ATLAS-CONF-2016-030
-1 = 13 TeV, 3.4 fbs
Dijet TLA
Dije
t + IS
R
ATLAS-CONF-2016-070
-1 = 13 TeV, 15.5 fbs
Dijet + ISR
γ+missTE
Eur. Phys. J. C 77 (2017) 393
-1 = 13 TeV, 36.1 fbs
γ+missTE
+jetmissTE
ATLAS-CONF-2017-060
-1 = 13 TeV, 36.1 fbs
+jetmissTE
+ZmissTE
ATLAS-CONF-2017-040
-1 = 13 TeV, 36.1 fbs
+ZmissTE
DM
Mas
s = M
ediat
or M
ass
×2
= 0
.12
2hcΩ
Therm
al Reli
c
S. Alderweireldt ATLAS results on searches for exotic new particles (28/Mar 2018) 2 / 24
OverviewSearch for Higgs decays to beyond the standard model light gaugebosons in four-lepton events with the ATLAS detector at
√s = 13 TeV
H(125)→ XX → 4l EXOT-2016-22 W leptonic low mass
Search for doubly charged Higgs boson production in multi-leptonfinal states with the ATLAS detector using proton–proton collisions at√
s = 13 TeV
pp → H++H−−→ l+l+l−l−EXOT-2016-07 W leptonic high mass
Search for heavy resonances decaying into a W or Z boson and a Higgsboson in final states with leptons and b-jets in 36 fb−1 of
√s = 13 TeV
pp collisions with the ATLAS detector
V ′ → VH→ (lν/ll/νν)bb EXOT-2016-10 W semi-leptonic
intermediate/high mass
Search for WW/WZ resonance production in lνqq final states in ppcollisions at
√s = 13 TeV with the ATLAS detector
X → WV → lνqq EXOT-2016-28 W semi-leptonic
intermediate/high mass
Search for light resonances decaying to boosted quark pairs and pro-duced in association with a photon or a jet in proton–proton colli-sions at
√s = 13 TeV with the ATLAS detector
ISR(γ/j)+ boosted jjEXOT-2017-01 W hadronic low mass
Search for dark maer and other new phenomena in events with anenergetic jet and large missing transverse momentum using theATLAS detector
jet + EmissT EXOT-2016-27 W hadronic high mass
Search for pair production of up-type vector-like quarks and 4t-quarkevents in final states with multiple b-jets with the ATLAS detector
TT → Ht + X EXOT-2016-13 W hadronic high mass
Search for W ′ → tb decays in the hadronic final state using ppcollisions at
√s = 13 TeV with the ATLAS detector
W ′ → tb EXOT-2017-02 W hadronic high mass
A search for high-mass resonances decaying to τν in pp collisions at√s = 13 TeV with the ATLAS detector
W ′ → τν EXOT-2017-06 W hadronic high mass
S. Alderweireldt ATLAS results on searches for exotic new particles (28/Mar 2018) 3 / 24
OverviewSearch for Higgs decays to beyond the standard model light gaugebosons in four-lepton events with the ATLAS detector at
√s = 13 TeV
H(125)→ XX → 4l EXOT-2016-22 W leptonic low mass
Search for doubly charged Higgs boson production in multi-leptonfinal states with the ATLAS detector using proton–proton collisions at√
s = 13 TeV
pp → H++H−−→ l+l+l−l−EXOT-2016-07 W leptonic high mass
Search for heavy resonances decaying into a W or Z boson and a Higgsboson in final states with leptons and b-jets in 36 fb−1 of
√s = 13 TeV
pp collisions with the ATLAS detector
V ′ → VH→ (lν/ll/νν)bb EXOT-2016-10 W semi-leptonic
intermediate/high mass
Search for WW/WZ resonance production in lνqq final states in ppcollisions at
√s = 13 TeV with the ATLAS detector
X → WV → lνqq EXOT-2016-28 W semi-leptonic
intermediate/high mass
Search for light resonances decaying to boosted quark pairs and pro-duced in association with a photon or a jet in proton–proton colli-sions at
√s = 13 TeV with the ATLAS detector
ISR(γ/j)+ boosted jjEXOT-2017-01 W hadronic low mass
Search for dark maer and other new phenomena in events with anenergetic jet and large missing transverse momentum using theATLAS detector
jet + EmissT EXOT-2016-27 W hadronic high mass
Search for pair production of up-type vector-like quarks and 4t-quarkevents in final states with multiple b-jets with the ATLAS detector
TT → Ht + X EXOT-2016-13 W hadronic high mass
Search for W ′ → tb decays in the hadronic final state using ppcollisions at
√s = 13 TeV with the ATLAS detector
W ′ → tb EXOT-2017-02 W hadronic high mass
A search for high-mass resonances decaying to τν in pp collisions at√s = 13 TeV with the ATLAS detector
W ′ → τν EXOT-2017-06 W hadronic high mass
S. Alderweireldt ATLAS results on searches for exotic new particles (28/Mar 2018) 3 / 24
Higgs decays to light bosons H(125)→ XX → 4l
motivation: higgs portal models, hidden sectors, dark maer
→ seing upper limits on the Higgs boson branching ratio to BSM particles
three analysis regions targeing dierent processes∎ H(125)→ZX→4l (2l2e and 2l2µ)
∎ H(125)→XX→4l, m(X) ∈ [15,60] GeV (4e, 2e2µ and 4µ)
∎ H(125)→XX→4l, m(X) ∈ [1,15] GeV (4µ)
X is new vector boson Zd or pseudoscalar a with low mass
[GeV]⟩ll
m⟨2 4 6 8 10 12 14 16 18
Eve
nts
/ 0.2
GeV
0.002
0.004
0.006
0.008
0.01
0.012
0.014 Data Total BackgroundHeavy Flavour VVV/VBS
4l→*
ZZ 4l→ ZZ* →H
ATLAS-113 TeV, 36.1 fb
4l→ XX →H
[GeV]⟩ll
m⟨0 10 20 30 40 50 60
Eve
nts
/ GeV
3−10
2−10
1−10
1
10
210Data Total BackgroundReducible bkg )Υ/Ψ/J/tZ+(tVVV/VBS 4l→ZZ*→H
4l→ZZ* =15 GeVZdm=35 GeVZdm =55 GeVZdm
ATLAS-113 TeV, 36.1 fb
4l→ XX →H
lept
onic
–EX
OT-
2016
-22W
S. Alderweireldt ATLAS results on searches for exotic new particles (28/Mar 2018) 4 / 24
Higgs decays to light bosons H(125)→ XX → 4l
set 95% CL upper limits on the fiducial cross sectionfor H→ZX→4l & H→XX→4l (model independent)
upper limits are applicable to any model with H(125) decays to 4 leptonsvia two intermediate, on-shell, narrow, promptly-decaying bosons
[GeV]Xm10 20 30 40 50 60
[fb]
fidσ95
% C
L up
per
limit
on
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
0.5
Expectedσ 2±
Observed
µ 4µ4e 2e2ATLAS
-113 TeV, 36.1 fb
4l→ XX →H
15 20 25 30 35 40 45 50 55
[GeV]Xm
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
[fb
]fids
95%
CL u
pper
limit o
n
2l2e m2l2
Observed
Expected
s 2±
ATLAS
4l® ZX®H1
13 TeV, 36.1 fb
H(125)→XX→4l H(125)→ZX→4l
lept
onic
–EX
OT-
2016
-22W
S. Alderweireldt ATLAS results on searches for exotic new particles (28/Mar 2018) 5 / 24
Doubly Charged Higgs pp → H++H−− → l+l+l−l−
Eve
nts
1−10
1
10
210
310
410
510
CRs VRs SRs
ATLAS1=13 TeV, 36.1 fbs
Data Total SM
DrellYan Diboson
Fakes Top
±
e±e
±
e±e±
e
±
l± µ±e
±
µ± µ± µ
±
l±
l± l± l
±e±
e
± µ±e
± µ± µ
±
e±e±
e
±
l± µ±e
±
µ± µ± µ
±
l’± l± l
±
l±
l± l± l
±e±
e
± µ±e
± µ± µ
±
e±e±
e
±l± µ±
e
±
µ± µ± µ
±
l’± l± l
±
l±
l± l± l
Data
/SM
0.5
1
1.5
Eve
nts
0
10
20
30
40
50ATLAS
1=13 TeV, 36.1 fbs
)±µ±SR1P2L (e
Data Total SM
Diboson FakesTop
(X) = 80%B) = 20%, ±µ±(eB
) = 450 GeV± ±m(H
(X) = 50%B) = 50%, ±µ±(eB
) = 650 GeV± ±m(H
(X) = 50%B) = 50%, ±µ±(eB
) = 850 GeV± ±m(H
) [GeV]±µ±m(e300 400 500 1000 2000
Data
/SM
00.5
11.5
2
dedicated 2-, 3-, and 4-lepton channels to optimize signal acceptance
fit invariant mass∎ invariant mass of same-charge lepton pair in 2- and 3-lepton channels∎ average mass in 4-lepton channel
dominant systematic uncertainties∎ fake leptons∎ charge misidentification∎ background estimation
lept
onic
–EX
OT-
2016
-07W
S. Alderweireldt ATLAS results on searches for exotic new particles (28/Mar 2018) 6 / 24
Doubly Charged Higgs pp → H++H−− → l+l+l−l−
) [GeV]±±m(H
300 400 500 600 700 800 900 1000 1100 1200
[fb]
)--
H+
+ H
→(p
pσ
2−10
1−10
1
10
210
310Observed 95% CL limitExpected 95% CL limit
σ 1±Expected limit σ 2±Expected limit
)--LH++
L H→(ppσ
)--RH++
R H→(ppσ
ATLAS-1 = 13 TeV, 36.1 fbs
)=30%±e±(eB)=40%±µ±(eB)=30%±µ±µ(B
) lim
it [
Ge
V]
Le
xp
ecte
d 9
5%
CL
m(H
840
845
850
855
860
850 849 847 846 846 847 848 849 851 854 857
848 847 845 844 844 844 845 847 849 852
846 845 843 842 842 842 843 845 847
845 844 842 841 841 841 842 843
845 843 841 840 840 840 841
845 843 842 841 841 840
846 845 843 843 842
849 847 846 845
852 851 850
857 856
863
) [%]±e± e→±±L
(HB
0 20 40 60 80 100
) [%
]± µ± µ
→±± L(H
B
0
20
40
60
80
100 ATLAS1=13 TeV, 36.1 fbs
)=100%±l± l→±±L
(HB
set lower limit on m(H±±) at 95% CL
B(H±±→e±e±) + B(H±±
→e±µ±) + B(H±±→ µ±µ±) = B(H±±
→l±l±)
mass limit derived for all combinations of the partial branching ratios∎ lower limit above 770 (450) GeV for B(H±±→l±l±) = 100(10)% for H±±L∎ lower limit above 670 (320) GeV for B(H±±→l±l±) = 100(10)% for H±±R
lept
onic
–EX
OT-
2016
-07W
S. Alderweireldt ATLAS results on searches for exotic new particles (28/Mar 2018) 7 / 24
Doubly Charged Higgs pp → H++H−− → l+l+l−l−
the muon channel is the most powerful, but the dierences are small
minimum limit as a function of B(H±±→l±l±)
limits derived for H±±L and H±±
R∎ lower limit above 770 (450) GeV for B(H±±→l±l±) = 100(10)% for H±±L∎ lower limit above 670 (320) GeV for B(H±±→l±l±) = 100(10)% for H±±R
) [GeV]±±L
m(H
300 400 500 600 700 800 900 1000
X)
[%]
→±± L(H
B)
= 1
± l± l
→±± L(H
B
1
2
34
10
20
3040
100
Observed 95% CL limit
Expected 95% CL limitσ1±Expected limit
σ2±Expected limit
ATLAS1=13 TeV, 36.1 fbs)±±
Llower limit of m(H
minimum limit) [GeV]±±
Lm(H
300 400 500 600 700 800 900 1000
X)
[%]
→±± L(H
B)
= 1
±
e± e
→±± L(H
B
1
2
34
10
20
3040
100
Observed 95% CL limit
Expected 95% CL limitσ1±Expected limit
σ2±Expected limit
ATLAS1=13 TeV, 36.1 fbs)±±
Llower limit of m(H
) [GeV]±±L
m(H
300 400 500 600 700 800 900 1000
X)
[%]
→±± L(H
B)
= 1
± µ± µ
→±± L(H
B
1
2
34
10
20
3040
100
Observed 95% CL limit
Expected 95% CL limitσ1±Expected limit
σ2±Expected limit
ATLAS1=13 TeV, 36.1 fbs)±±
Llower limit of m(H
) [GeV]±±L
m(H
300 400 500 600 700 800 900 1000
X)
[%]
→±± L(H
B)
= 1
± µ±
e→±± L
(HB
1
2
34
10
20
3040
100
Observed 95% CL limit
Expected 95% CL limitσ1±Expected limit
σ2±Expected limit
ATLAS1=13 TeV, 36.1 fbs)±±
Llower limit of m(H
e±e±
µ±µ±
e±µ±
lept
onic
–EX
OT-
2016
-07W
S. Alderweireldt ATLAS results on searches for exotic new particles (28/Mar 2018) 8 / 24
OverviewSearch for Higgs decays to beyond the standard model light gaugebosons in four-lepton events with the ATLAS detector at
√s = 13 TeV
H(125)→ XX → 4l EXOT-2016-22 W leptonic low mass
Search for doubly charged Higgs boson production in multi-leptonfinal states with the ATLAS detector using proton–proton collisions at√
s = 13 TeV
pp → H++H−−→ l+l+l−l−EXOT-2016-07 W leptonic high mass
Search for heavy resonances decaying into a W or Z boson and a Higgsboson in final states with leptons and b-jets in 36 fb−1 of
√s = 13 TeV
pp collisions with the ATLAS detector
V ′ → VH→ (lν/ll/νν)bb EXOT-2016-10 W semi-leptonic
intermediate/high mass
Search for WW/WZ resonance production in lνqq final states in ppcollisions at
√s = 13 TeV with the ATLAS detector
X → WV → lνqq EXOT-2016-28 W semi-leptonic
intermediate/high mass
Search for light resonances decaying to boosted quark pairs and pro-duced in association with a photon or a jet in proton–proton colli-sions at
√s = 13 TeV with the ATLAS detector
ISR(γ/j)+ boosted jjEXOT-2017-01 W hadronic low mass
Search for dark maer and other new phenomena in events with anenergetic jet and large missing transverse momentum using theATLAS detector
jet + EmissT EXOT-2016-27 W hadronic high mass
Search for pair production of up-type vector-like quarks and 4t-quarkevents in final states with multiple b-jets with the ATLAS detector
TT → Ht + X EXOT-2016-13 W hadronic high mass
Search for W ′ → tb decays in the hadronic final state using ppcollisions at
√s = 13 TeV with the ATLAS detector
W ′ → tb EXOT-2017-02 W hadronic high mass
A search for high-mass resonances decaying to τν in pp collisions at√s = 13 TeV with the ATLAS detector
W ′ → τν EXOT-2017-06 W hadronic high mass
S. Alderweireldt ATLAS results on searches for exotic new particles (28/Mar 2018) 9 / 24
Heavy resonance → VH in semi-leptonic decaysW ′/Z ′/ggF A/bbA→ VH → (lν/ll/νν)bb
motivation: heavy resonances, 2HDM, heavy vector triplets, . . .
analysis setup using dedicated categories∎ 0-2 lepton channels
∎ resolved or merged bb regimes (small- and large-R jets)
∎ various multiplicities of main and additional b-jets
reconstruced resonance mass dependent on channel: mVh and mT ,Vh
Eve
nts/
GeV
4−10
3−10
2−10
1−10
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410
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610 data1.5 TeV HVT x 10
, single topttW+(bb,bc,cc)W+(bl,cl), W+lZ+(bb,bc,cc)Z+(bl,cl), Z+lmultijetotheruncertainty
ATLAS-1 = 13 TeV, 36.1 fbs
2 jets≥1 lep., 2 jets, 1 b-tag≥1 lep.,
< 140 GeVjj110 GeV < m
[GeV]Vhm300 1000 2000da
ta /
bkg
0.5
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nts/
GeV
5−10
4−10
3−10
2−10
1−10
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610 data1.5 TeV HVT x 10
, single topttW+(bb,bc,cc)W+(bl,cl), W+lZ+(bb,bc,cc)Z+(bl,cl), Z+lotheruncertainty
ATLAS-1 = 13 TeV, 36.1 fbs
2 jets≥2 lep., 2 jets, 2 b-tags≥2 lep.,
< 145 GeVjj100 GeV < m
[GeV]Vhm300 1000 2000 3000da
ta /
bkg
0.5
1
1.5
Eve
nts/
GeV
5−10
4−10
3−10
2−10
1−10
1
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410 data1.5 TeV HVT x 10
, single topttW+(bb,bc,cc)W+(bl,cl), W+lZ+(bb,bc,cc)Z+(bl,cl), Z+lotheruncertainty
ATLAS-1 = 13 TeV, 36.1 fbs
1 large-R jets≥0 lep., 1 large-R jets≥0 lep.,
2 b-tags, 0 add. b-tags
< 145 GeVJ75 GeV < m
[GeV]T,Vhm500 1000 2000 3000da
ta /
bkg
0.5
1
1.5
resolved, 1 lep, 2+ jets, 1 b-tag resolved, 2 lep, 2+ jets, 2 b-tags merged, 0 lep, 1+ large-R jet, 2+0 b-tags
sem
i-le
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Heavy resonance → VH in semi-leptonic decaysW ′/Z ′/ggF A/bbA→ VH → (lν/ll/νν)bb
95% CL upper limits for Z′→Zh & W′→Wh production
observed exclusion contours in the HVT parameter space
95% CL upper limits for A→Zh with h→bb
interpretations following various models available in the paper
[GeV]Z’m500 1000 1500 2000 2500 3000 3500 4000 4500 5000
) [p
b]c
,cbb→
B(h
⋅Z
h)→
Z’
→(p
pσ
4−10
3−10
2−10
1−10
1
10 ATLAS
-1 = 13 TeV, 36.1 fbs
95% CL limit
Observed (CLs)
Expected (CLs)
σ1±Expected
σ2±Expected
=1V
HVT Model A, g
=3V
HVT Model B, g
HcV
g3− 2− 1− 0 1 2 3
V /
gFc2 g
0.6−
0.4−
0.2−
0
0.2
0.4
0.6ATLAS
= 13 TeVs-136.1 fb
1.2 TeV
2.0 TeV
3.0 TeV
=1)v
A(g
=3)v
A(g
=3)v
B(g
[GeV]A m
200 400 600 800 1000 1200 1400 1600 1800 2000
) [p
b]b
b→
B(h
⋅Z
h)→
A→
(pp
σ
3−10
2−10
1−10
1
10Observed (CLs)Expected (CLs)
σ 1±Expected σ 2±Expected
b b→Zh , h→Agluon-gluon fusion
ATLAS-1 = 13 TeV, 36.1 fbs
95% CL limit
Z′→Zh HVT exclusion contours A→Zh with h→bb
sem
i-le
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Heavy resonance → WV in semi-leptonic decaysX →WV → lνqq
motivation: composite H, extra dimensions, heavy vector triplets, . . .
analysis using dedicated categorization∎ merged (lvJ) or resolved (lvjj) quark pair∎ low- or high purity boson tagging (D2)∎ WW or WZ signal∎ DY or VBF production
Resolved CRResolved
CR
mjj [GeV]66 82 94 106 200
Resolved SR (WW)ResolvedSR (WZ) HP CRHP
CR
LP CR LP CR
D2
mJ [GeV]50
LP SR (WW) LP SR (WZ)HP SR (WW) HP SR (WZ)
(β=1
)
mW mZ
εV=50%
εV=80%
resolved merged
0 0.5 1 1.5 2 2.5 3 3.5 4
Events
/ 0
.4
1-10
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910
1010Data
W+jets
tt
Singlet
Dibosons
Z+jets
Postfit uncertainty
HVT Model A Z´ 1.0 TeV
Data
W+jets
tt
Singlet
Dibosons
Z+jets
Postfit uncertainty
HVT Model A Z´ 1.0 TeV
ATLAS
1 = 13 TeV, 36.1 fbs
CategoryqggF/q
2D
0 0.5 1 1.5 2 2.5 3 3.5 4
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D2 variable
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Heavy resonance → WV in semi-leptonic decaysX →WV → lνqq
motivation: composite H, extra dimensions, heavy vector triplets, . . .
analysis using dedicated categorization∎ merged (lvJ) or resolved (lvjj) quark pair∎ low- or high purity boson tagging (D2)∎ WW or WZ signal∎ DY or VBF production
perform simultaneous binned ML fitto m(WV) distributions
Events
/ 0
.34 T
eV
1
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210
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410 DataW+jetstt
Single tDibosonsZ+jetsPostfit uncertaintyHVT VBF Model Z´
500)´1200 GeV (
ATLAS1
= 13 TeV, 36.1fbsWW Signal Region (HP)VBF Category
[TeV]Jnlm0.6 0.8 1 1.2 1.4 1.6 1.8 2 2.2 2.4
Data
/ S
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.42 T
eV
1
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510
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710DataW+jetstt
Single tDibosonsZ+jetsPostfit uncertaintyHVT Model A W´
5)´2000 GeV (
ATLAS1
= 13 TeV, 36.1fbsWZ Signal Region (LP)
CategoryqggF/q
[TeV]Jnlm0.5 1 1.5 2 2.5 3 3.5 4
Data
/ S
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/ 0
.525 T
eV
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610Data
W+jets
ttMisid. lepton
Single t
Dibosons
Z+jetsPostfit uncertainty
HVT VBF Model Z´
500)´500 GeV (
ATLAS1
= 13 TeV, 36.1fbsWW Signal Region (Res.)VBF Category
[TeV]jjnl
m0.4 0.6 0.8 1 1.2 1.4
Data
/ S
M
0.5
1
1.5
merged, VBF, WW, high-purity merged, ggF, WZ, low-purity resolved, VBF, WW
sem
i-le
pton
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Heavy resonance → WV in semi-leptonic decaysX →WV → lνqq 95% CL upper limits for various models; more in the paper
largest excess 2.7σ local
m(Z´) [TeV]0.5 1 1.5 2 2.5 3 3.5 4 4.5 5
WW
) [p
b]
®Z
´®
(pp
s
310
210
110
1
10
210
310ATLAS
1 = 13 TeV, 36.1 fbsqq Categoryn lqggF/q
HVT model Z´
Observed 95% CL upper limit
Expected 95% CL upper limit
)s 1±Expected limit (
)s 2±Expected limit (
=1v
WW) HVT Model A, g®Z´®(pps
=3v
WW) HVT Model B, g®Z´®(pps
m(Scalar) [TeV]0.5 1 1.5 2 2.5 3
WW
jj) [
pb
]®
Hjj
®(p
ps
310
210
110
1
10
210
310ATLAS
1 = 13 TeV, 36.1 fbsVBF lvqq CategoryHeavy scalar model
Observed 95% CL upper limit
Expected 95% CL upper limit
)s 1±Expected limit (
)s 2±Expected limit (
m(W´) [TeV]0.5 1 1.5 2 2.5 3 3.5 4 4.5 5
WZ
) [p
b]
®W
´®
(pp
s
310
210
110
1
10
210
310ATLAS
1 = 13 TeV, 36.1 fbsqq Categoryn lqggF/q
HVT model W´
Observed 95% CL upper limit
Expected 95% CL upper limit
)s 1±Expected limit (
)s 2±Expected limit (
=1v
WZ) HVT Model A, g®W´®(pps
=3v
WZ) HVT Model B, g®W´®(pps
) [TeV]KK
m(G0.5 1 1.5 2 2.5 3 3.5 4 4.5 5
WW
) [p
b]
®K
KG®
(pp
s310
210
110
1
10
210
310ATLAS
1 = 13 TeV, 36.1 fbsqq Categoryn lqggF/q
=1.0plMBulk RS model k/
Observed 95% CL upper limit
Expected 95% CL upper limit
)s 1±Expected limit (
)s 2±Expected limit (
=1pl
MWW) k/®KK
G®(pps
VBF, HVT model Z′ VBF, Heavy-scalar model
ggF, HVT model W′ ggF, graviton model
sem
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OverviewSearch for Higgs decays to beyond the standard model light gaugebosons in four-lepton events with the ATLAS detector at
√s = 13 TeV
H(125)→ XX → 4l EXOT-2016-22 W leptonic low mass
Search for doubly charged Higgs boson production in multi-leptonfinal states with the ATLAS detector using proton–proton collisions at√
s = 13 TeV
pp → H++H−−→ l+l+l−l−EXOT-2016-07 W leptonic high mass
Search for heavy resonances decaying into a W or Z boson and a Higgsboson in final states with leptons and b-jets in 36 fb−1 of
√s = 13 TeV
pp collisions with the ATLAS detector
V ′ → VH→ (lν/ll/νν)bb EXOT-2016-10 W semi-leptonic
intermediate/high mass
Search for WW/WZ resonance production in lνqq final states in ppcollisions at
√s = 13 TeV with the ATLAS detector
X → WV → lνqq EXOT-2016-28 W semi-leptonic
intermediate/high mass
Search for light resonances decaying to boosted quark pairs and pro-duced in association with a photon or a jet in proton–proton colli-sions at
√s = 13 TeV with the ATLAS detector
ISR(γ/j)+ boosted jjEXOT-2017-01 W hadronic low mass
Search for dark maer and other new phenomena in events with anenergetic jet and large missing transverse momentum using theATLAS detector
jet + EmissT EXOT-2016-27 W hadronic high mass
Search for pair production of up-type vector-like quarks and 4t-quarkevents in final states with multiple b-jets with the ATLAS detector
TT → Ht + X EXOT-2016-13 W hadronic high mass
Search for W ′ → tb decays in the hadronic final state using ppcollisions at
√s = 13 TeV with the ATLAS detector
W ′ → tb EXOT-2017-02 W hadronic high mass
A search for high-mass resonances decaying to τν in pp collisions at√s = 13 TeV with the ATLAS detector
W ′ → τν EXOT-2017-06 W hadronic high mass
S. Alderweireldt ATLAS results on searches for exotic new particles (28/Mar 2018) 15 / 24
Light resonances decaying to boosted quark pairsISR(γ/j) + boosted jj motivation: many models with mediators coupling to quarks & gluons
∎ look at lower mass with ISR (mZ ′ < 200 GeV)∎ ISR allows highly eicient triggering at lower masses
(compared to regular triggering on the resonance decay products)
topologies:∎ 1 isolated γ + 1 large-R jet ∎ 1 small-R jet + 1 large-R jet
making use of τ21 substructure variable and Designed Decorrelated Tagger(DDT;removing dependence of τ21 on jet mass and pT )
∎ τN a measure of a jet’s compatibility with being fully aligned along N axes
∎ τ21 = τ2/τ1 dierentiates two-particle jets from the decay ofa boosted resonance & a single-particle jet
∎ aim to separate large-R signal jets and QCD γ+jet background
background estimate using transfer factor method
jet mass [GeV]RLarge-50 100 150 200 250 300
⟩ D
DT
21τ ⟨
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
SimulationATLAS = 13 TeVs
Jet channel
< 700 GeVJ
TBkg., 500 < p < 700 GeVJ
TSig., 500 < p
< 900 GeVJ
TBkg., 700 < p < 900 GeVJ
TSig., 700 < p
< 1300 GeVJ
TBkg., 900 < p < 1300 GeVJ
TSig., 900 < p
jet mass [GeV]RLarge-50 100 150 200 250 300
⟩ D
DT
21τ ⟨
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
SimulationATLAS = 13 TeVs
Photon channel
< 700 GeVJ
TBkg., 500 < p < 700 GeVJ
TSig., 500 < p
< 900 GeVJ
TBkg., 700 < p < 900 GeVJ
TSig., 700 < p
< 1300 GeVJ
TBkg., 900 < p < 1300 GeVJ
TSig., 900 < p
jet
γ
hadr
onic
–EX
OT-
2017
-01W
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Light resonances decaying to boosted quark pairsISR(γ/j) + boosted jj
fit of large-R jet mass in jet & photon channels∎ background estimated separately per candidate mass
95% CL limits on the Z′ cross section
channels combined for limit on coupling gq
largest excess in the jet (γ) channel at mZ ′ = 150(140) GeV with local significance 2.5 (2.2)σ
Eve
nts
/ GeV
10
210
310
410
510
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710 ATLAS
-1 = 13 TeV, 36.1 fbsJet channel
SR
DataBackground est.W/Z + jetsZ' (220 GeV)Bkg. stat. uncert.
syst.⊕Bkg. stat.
jet mass [GeV]RLarge-50 100 150 200 250 300
Dat
a / e
st.
0.98
0.99
1
1.01
1.02
Eve
nts
/ GeV
1
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610 ATLAS
-1 = 13 TeV, 36.1 fbsPhoton channel
SR
DataBackground est.
γW/Z + Z' (160 GeV)Bkg. stat. uncert.
syst.⊕Bkg. stat.
jet mass [GeV]RLarge-50 100 150 200 250 300
Dat
a / e
st.
0.9
1
1.1
[GeV]Z’m
100 120 140 160 180 200 220
A [
pb
]´
) ®
Z’
® (
pp
s
2-10
1-10
1
10
210
=0.5)q
Theory (g
Observed 95% CL limit
Expected 95% CL limit
s1 ±Expected limit
s2 ±Expected limit
ATLAS
1 = 13 TeV, 36.1 fbs
Jet channel
[GeV]Z’m
100 120 140 160 180 200 220
A [
pb
]´
) ®
Z’
® (
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s
3-10
2-10
1-10
1
10
=0.5)q
Theory (g
Observed 95% CL limit
Expected 95% CL limit
s1 ±Expected limit
s2 ±Expected limit
ATLAS
1 = 13 TeV, 36.1 fbs
Photon channel
[GeV]Z’m
100 120 140 160 180 200 220
qg
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
Observed 95% CL limit
Expected 95% CL limit
s1 ±Expected limit
s2 ±Expected limit
ATLAS
1 = 13 TeV, 36.1 fbs
hadr
onic
–EX
OT-
2017
-01W
S. Alderweireldt ATLAS results on searches for exotic new particles (28/Mar 2018) 17 / 24
Monojets and missing transverse momentumjet + Emiss
T motivation: dark maer, compressed SUSY, extra dimensions, . . .∎ many possible diagrams
requiring: large missing transverse energy + 1 high-pT jet + ≤3 more jets (pT >30 GeV) + no leptons
background is constrained using a likelihood fit to the EmissT distribution in a set of control regions,
taking into account systematic uncertainties
300 400 500 600 700 800 900 1000 1100 1200
Events
/ G
eV
1-10
1
10
210
310
410
510
610
710Data 2015+2016
Standard Model
) + jetsnn ®Z(
) + jetsn l®W(
ll) + jets®Z(
+ single toptt
Diboson
multijets + ncb
) = (500, 495) GeV0
)c~, b~
m(
)= (400, 1000) GeVmed
, MDM
(m
=6400 GeVD
ADD, n=4, M
ATLAS1 = 13 TeV, 36.1 fbs
Signal Region>250 GeV
miss
T(j1)>250 GeV, E
Tp
[GeV]missTE
300 400 500 600 700 800 900 1000 1100 1200
Data
/ S
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1.2Stat. + Syst. Uncertainties
Events
/ 5
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510
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810
ATLAS 1 = 13 TeV, 36.1 fbs
Signal Region>250 GeV
miss
T(j1)>250 GeV, E
Tp
Data 2015+2016
Standard Model
) + jetsnn ®Z(
) + jetsn l®W(
ll) + jets®Z(
+ single toptt
Diboson
) = (500, 495) GeV0c~, b
~m(
)= (400, 1000) GeVmed
, MDM
(m
=6400 GeVD
ADD, n=4, M
[GeV]T
Leading jet p400 600 800 1000 1200 1400
Data
/ S
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1.2 Stat. + Syst. Uncertainties
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OT-
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Monojets and missing transverse energymonojet + Emiss
T seing model-independent limits using inclusive signal regions
providing exclusion limits for a wide range of models (more in the paper)
[GeV]AZm
0 1000 2000
[GeV
]χ
m
0
500
1000expσ 2 ±Expected limit
)expσ 1 ±Expected limit (
)PDF, scaletheoryσ 1 ±Observed limit (
Perturbativity Limit
Relic Density (MadDM)-1 = 13 TeV, 3.2 fbsATLAS
ATLAS-1 = 13 TeV, 36.1 fbs
Axial-Vector Mediator
Dirac Fermion DM
= 1.0χ
= 0.25, gq
g
95% CL limits
χ
= 2
mAZm
[GeV]χm1 10 210 310 410
]2-p
roto
n) [c
mχ
(S
Dσ
46−10
44−10
42−10
40−10
38−10
36−10
PICO-60
Axial-Vector Mediator
90% CL limits
Dirac Fermion DM
= 1.0χ
= 0.25, gq
g
ATLAS-1 = 13 TeV, 36.1 fbs
[GeV]VZm
0 1000 2000
[GeV
]χ
m
0
500
1000 expσ 2 ±Expected limit
)expσ 1 ±Expected limit (
)PDF, scaletheory
σ 1 ±Observed limit (
Relic Density (MadDM)
ATLAS-1 = 13 TeV, 36.1 fbs
Vector Mediator
Dirac Fermion DM
= 1.0χ
= 0.25, gq
g
95% CL limits
χ
= 2
mVZm
[GeV]1t~m
300 400 500 600
[GeV
]10
χ∼m
250
300
350
400
450
500
550
600
650-1=13 TeV, 36.1 fbs
1
0χ∼c→
1t~
production, 1t~1t~
All limits at 95% CL
ATLAS
-1=13 TeV, 3.2 fbsATLAS
)theory
SUSYσ1 ±Observed limit (
)expσ1 ±Expected limit (
expσ2 ±Expected limit
c+ m
0
1χ∼
< m
1t~m
W+ m
b+ m
0
1χ∼
> m
1t~m
Number of extra dimensions
2 3 4 5 6
[TeV
]D
Low
er li
mit
on M
3
4
5
6
7
8
9
10
11
Observed limitσ 1 ±Observed limit
Expected limitσ 1 ±Expected limit σ 2 ±Expected limit
-1 = 13 TeV, 3.2 fbsATLAS
ATLAS
> 400 GeVmiss
T95% CL Limits, E
-1 = 13 TeV, 36.1 fbs
DM axial-vector
→
DM vector
SUSY t extra dimensions
hadr
onic
–EX
OT-
2016
-27W
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Pair production of vector-like quarks TT → Ht + X
motivation: alternative for 4th generation quarks; hierarchy problemdecays to vector bosons and 3rd generation quarks
approach: 0/1-lepton + (many) jets, some b-tagged∎ 1-lepton = lepton + jets: sensitive to T → tH(bb) (12 regions)
∎ 0-lepton = jets + MET: sensitive to T → tZ(νν) (22 regions)
make use of Higgs and top tagging: categorize using N(H), N(t), N(b), N(j) multiplicities
ML fit of eective mass
derive 95% CL limit on production cross section
Top-tagged jet multiplicity0 1 2 3 4 5
Fra
ctio
n of
eve
nts
0
0.2
0.4
0.6
0.8
1
1.2
2b≥7j, ≥0-lepton =13 TeVs
Simulation PreliminaryATLAS
Total background doublet (1 TeV)TT singlet (1 TeV)TT
(1 TeV)t ZtZ→ TT
6j, 3
b≥
0t, 0
H,
6j, 3
b≥
1t, 0
H,
6j, 3
b≥
0t, 1
H,
6j, 3
b≥
1t, 1
H,
6j, 3
b≥
2t, 0
-1H
, ≥
6j, 3
b≥
2H,
≥0t
, ≥
4b≥6j
, ≥
0t, 0
H,
4b≥6j
, ≥
1t, 0
H,
4b≥6j
, ≥
0t, 1
H,
4b≥6j
, ≥
1t, 1
H,
4b≥6j
, ≥
2t, 0
-1H
, ≥
4b≥6j
, ≥
2H,
≥0t
, ≥
7j, 2
b, H
M≥
0t, 0
H,
7j, 2
b, H
M≥
1t, 0
H,
7j, 2
b, H
M≥
0t, 1
H,
7j, 2
b, H
M≥
2tH
, ≥
7j, 3
b, L
M≥
0t, 0
H,
7j, 3
b, L
M≥
1t, 0
H,
7j, 3
b, L
M≥
0t, 1
H,
7j, 3
b, L
M≥
1t, 1
H,
7j, 3
b, L
M≥
2t, 0
-1H
, ≥
7j, 3
b, H
M≥
0t, 0
H,
7j, 3
b, H
M≥
1t, 0
H,
7j, 3
b, H
M≥
0t, 1
H,
7j, 3
b, H
M≥
1t, 1
H,
7j, 3
b, H
M≥
2t, 0
-1H
, ≥
7j, 3
b≥
2H,
≥0t
, ≥
4b, L
M≥
7j,
≥0t
, 0H
,
4b, L
M≥
7j,
≥1t
, 0H
,
4b, L
M≥
7j,
≥0t
, 1H
,
4b, H
M≥
7j,
≥0t
, 0H
,
4b, H
M≥
7j,
≥1t
, 0H
,
4b, H
M≥
7j,
≥0t
, 1H
,
4b≥7j
, ≥
2tH
, ≥
Dat
a / B
kg
00.5
11.5
2
Eve
nts
1
10
210
310
410
510 ATLAS Preliminary-1 = 13 TeV, 36.1 fbs
Search regionsPost-fit (Bkg-only)
Data + light-jetstt1c≥ + tt 1b≥ + tttNon-t Total Bkg unc.
1-lepton 0-lepton
[GeV]Tm
700 800 900 1000 1100 1200 1300 1400 1500
) [p
b]T
T→
(pp
σ
3−10
2−10
1−10
1
10)σ1±Theory (NNLO prediction
95% CL observed limit95% CL expected limit
σ1±95% CL expected limit σ2±95% CL expected limit
ATLAS Preliminary-1 = 13 TeV, 36.1 fbs
1-lepton + 0-lepton combination
SU(2) doublet
hadr
onic
–EX
OT-
2016
-13W
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Hadronic W′→ tb
motivation: universal extra dimensions, lile Higgs, top assistedtechnicolor, Kaluza-Klein gravitons, . . .∎ tb final state sensitive to right handed W′s
topology: 1 high-pT b-jet + 1 large-R top-jet (bqq) categorize:
∎ 0 or 1 b-tag∎ 6 regions each based on b- and top tagging criteria
making use of shower deconstruction top tagger [1] hps://journals.aps.org/prd/abstract/10.1103/PhysRevD.84.074002 W
[2] hps://journals.aps.org/prd/abstract/10.1103/PhysRevD.87.054012 W
Eve
nts
0
100
200
300
400
500
600
700 ATLAS-1 = 13 TeV, 36.1 fbsData
MCtt MCtNon t
SD unc.
| < 2.0Jη > 420 GeV, |J
Tp
)SD
χlog(-3 -2 -1 0 1 2 3 4 5 6 7D
ata
/ Pre
d.
00.5
11.5
2
hadr
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–EX
OT-
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-02W
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Hadronic W′→ tb
fit reconstructed mtb in signal and validation regions
derived 95% CL limits on the cross section
largest excess at m = 2.25 TeV with local significance of 2.0σ
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hadr
onic
–EX
OT-
2017
-02W
S. Alderweireldt ATLAS results on searches for exotic new particles (28/Mar 2018) 22 / 24
Heavy resonances decaying to taus W ′→ τν
motivation: W′ preferential coupling to 3rd gen as explanation for anomalies, mass hierarchy, . . .∎ might not appear in e/µ final states and therefore requires targeed τ search
selecting events with taus and large missing transverse energy
deriving model-independent 95% CL limits
interpretations in SSM and non-universal G(221)
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) X
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SSMW'
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hadr
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–EX
OT-
2017
-06W
S. Alderweireldt ATLAS results on searches for exotic new particles (28/Mar 2018) 23 / 24
Summary presented 9 recent ATLAS exotics searches using
the 2015+2016 dataset (36.1 fb−1)
results covering many final states anda wide range of masses
derivation of model-independent limits as well asinterpretations testing a large number of models
no hints of new physics yet
for the future
∎ more data to be analysed (2017+2018)
∎ several more results in the pipeline
∎ all public results at: hps://twiki.cern.ch/twiki/bin/view/AtlasPublic/ExoticsPublicResults W
OverviewSearch for Higgs decays to beyond the standard model light gaugebosons in four-lepton events with the ATLAS detector at
√s = 13 TeV
H(125)→ XX → 4l EXOT-2016-22 W leptonic low mass
Search for doubly charged Higgs boson production in multi-leptonfinal states with the ATLAS detector using proton–proton collisions at√
s = 13 TeV
pp → H++H−−→ l+l+l−l−EXOT-2016-07 W leptonic high mass
Search for heavy resonances decaying into a W or Z boson and a Higgsboson in final states with leptons and b-jets in 36 fb−1 of
√s = 13 TeV
pp collisions with the ATLAS detector
V ′ → VH→ (lν/ll/νν)bb EXOT-2016-10 W semi-leptonic
intermediate/high mass
Search for WW/WZ resonance production in lνqq final states in ppcollisions at
√s = 13 TeV with the ATLAS detector
X → WV → lνqq EXOT-2016-28 W semi-leptonic
intermediate/high mass
Search for light resonances decaying to boosted quark pairs and pro-duced in association with a photon or a jet in proton–proton colli-sions at
√s = 13 TeV with the ATLAS detector
ISR(γ/j)+ boosted jjEXOT-2017-01 W hadronic low mass
Search for dark maer and other new phenomena in events with anenergetic jet and large missing transverse momentum using theATLAS detector
jet + EmissT EXOT-2016-27 W hadronic high mass
Search for pair production of up-type vector-like quarks and 4t-quarkevents in final states with multiple b-jets with the ATLAS detector
TT → Ht + X EXOT-2016-13 W hadronic high mass
Search for W ′ → tb decays in the hadronic final state using ppcollisions at
√s = 13 TeV with the ATLAS detector
W ′ → tb EXOT-2017-02 W hadronic high mass
A search for high-mass resonances decaying to τν in pp collisions at√s = 13 TeV with the ATLAS detector
W ′ → τν EXOT-2017-06 W hadronic high mass
S. Alderweireldt ATLAS results on searches for exotic new particles (28/Mar 2018) 3 / 24
S. Alderweireldt ATLAS results on searches for exotic new particles (28/Mar 2018) 24 / 24
Backup
S. Alderweireldt ATLAS results on searches for exotic new particles (28/Mar 2018) 25 / 24
ATLAS
S. Alderweireldt ATLAS results on searches for exotic new particles (28/Mar 2018) 26 / 24
Jet substructure
DDTρ1 2 3 4 5 6
⟩ 21τ ⟨
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
SimulationATLAS = 13 TeVs
Jet channel < 700 GeVJ
TBkg., 500 < p
< 900 GeVJ
TBkg., 700 < p
< 1300 GeVJ
TBkg., 900 < p
< 700 GeVJ
TSig., 500 < p
< 1300 GeVJ
TSig., 900 < p
< 900 GeVJ
TSig., 700 < p
crucial tool in searches for resonances decaying to highly boosted
∎ quark pairs, SM bosons, top quarks
τ21 and D2 variables to track two-pronged signal jets [2],[3]
designed decorrelated tagger (DDT) [4] to remove dependence on mass & pT
important for∎ ISR + boosted quark pair∎ W ′ → tb∎ X →WV → lνqq
[1] R. Jansky W
[2] EXOT-2017-01 W
S. Alderweireldt ATLAS results on searches for exotic new particles (28/Mar 2018) 27 / 24
Jet substructure
[1] R. Jansky W
jet mass:
¿ÁÁÀ(∑
i∈J Ei)2
− (∑i∈J pi)
2
currently mostly using calorimeter-based jet substructure
gain from including tracker information in substructure measurements
S. Alderweireldt ATLAS results on searches for exotic new particles (28/Mar 2018) 28 / 24
Jetsresolved boosted/merged
[1] R. Jansky W
S. Alderweireldt ATLAS results on searches for exotic new particles (28/Mar 2018) 29 / 24