GGM1.5 SRee# - CERNR BR(τ 0 0.2 0.4 0.6 0.8 1) L τ BR(0 0.1 0.2 0.3 0.4 0.5 λ i3k = -λ 3ik 0 →...

GGM 1.5 SR ee

Emma Torró

(on behalf of the ATLAS Collabora;on)

Univ. of Washington -‐ SeaDle

Searches for R-‐Parity viola;ng SUSY with lepton number viola;on

SUSY 2015

Lake Tahoe, USA

28 August 2015 1

Introduc;on

2

R = (-‐1)3(B – L) +2s = +1 for SM par:cles -‐ 1 for SUSY par:cles

•  In this talk only Lepton Flavour Viola;ng terms (LFV) are considered.

For BNV see next talk by B. Jackson

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Emma Torró SUSY15 Lake Tahoe, 28 Aug. 2015

bilinear RPV terms (bRPV)

LLE terms

LQD terms

•  Lepton (L) and baryon (B) number viola;on are experimentally constrained but not forbidden by any fundamental reason. •  Standard SUSY searches assume R-‐Parity Conserva;on (RPC). •  Introducing non-‐zero RPV couplings ! rich phenomenology, can weaken mass and cross-‐ sec;on limits from collider experiments.

Introduc;on •  This talk presents the latest results from the ATLAS experiment:

•  20 ]-‐1 of pp LHC collision data at 8 TeV •  searches for RPV SUSY with LSPs decaying promptly through LFV couplings for:

•  Reinterpreta;on in terms of LFV-‐RPV of searches originally developed to target RPC models. •  This talk will focus more on the model descrip;on and interpreta;on of final results than on the analyses. 3

Simplified models pMSSM Ref.

Analysis short name

LLE (g̃g̃)

LQD (g̃g̃)

LQD (q̃q)̃

LLE + LQD

bRPV

4L ✓ Phys. Rev. D. 90, 052001 (2014)

SS/3L ✓ ✓ JHEP 06 (2014) 035

1L ✓ ✓ Phys. Rev. LeD. 114, 161801 (2015)

0L 2-‐6 jets ✓ ✓ JHEP 09 (2014) 176

0L 7-‐10 jets ✓ J. High Energy Phys. 10 (2013) 130

eμ, eτ, μτ ✓ Phys. Rev. LeD. 115, 031801 (2015)

B-‐L (Not covered in this talk. See backup for summary) ATLAS-‐CONF-‐2015-‐015

RPV summary pape

r:

ATLAS-‐CO

NF-‐2015-‐018

•  Dedicated analysis searching for heavy resonances


RPV summary paper

4 Emma Torró SUSY15 Lake Tahoe, 28 Aug. 2015

5

4L SS/3L 1L 0L

≥ 4 leptons (≥ 2 e or μ) no jet selec;on

•  DZ, ZZ (MC) •  Non-‐prompt and fake leptons (data driven)

•  Good agreement between expected and observed events in VRs and in SRs in all analyses.

2 SS OR 3 leptons 0 – 3 b-‐jets

•  Dbar and W+jets (Normalize MC to data in CRs)

•  W+jets, Dbar + single top, Z(νν) + jets, mul;jets. (Normalize MC to data in CRs)

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•  mul;jets (matrix method) •  Dbar and W+jets (Normalize MC to data in CR) •  Z+jets, DV, st (MC)

1 lepton 3 – 6 jets

no iso leptons ≥ 5 -‐ 6 jets pT(jet1) >160 GeV

no iso leptons 7 -‐ 10 jets pT > 50 or 80 GeV

•  See more details on every analysis in backup slides

Analyses considered for the RPV summary paper ATLAS-‐CONF-‐2015-‐018

[GeV]TmissE

250 300 350 400 450 500 550

Even

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GeV

0

5

10

15

20

25ATLAS

-1=8 TeV, 20.3 fbsµhard 1L e/

6-jet SR

DataStandard ModelTop QuarksV+jetsFake LeptonsDibosons

)=01χ∼, ±

1χ∼, g~ 1-step, m(g~g~

(1025, 545, 65) GeV

•  DW, DZ WW, WZ, ZZ + jets (MC) •  Fake leptons, charge-‐flip (data-‐driven)


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) LτBR

(

0

0.1

0.2

0.3

0.4

0.53ikλ = -i3kλ

ν-l+ l→ 0

1χ∼

ν

±

τ± l→ 01χ∼

ijkλ

ν-l+ l→ 0

1χ∼

3i3λ = -i33λ

ν

±

τ± l→ 01χ∼

ν-τ+τ → 01χ∼

ij3λ

ν

±

τ± l→ 01χ∼

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) Lτ →

BR(L

SP

0

0.1

0.2

0.3

0.4

0.5 GluinoELL

Models: LLE terms

LLE couplings with 1st-‐ and 2nd-‐genera;on leptons dominate

LLE couplings with 3rd-‐genera;on leptons dominate

•  Simplified model: neutralino LSP decays into two charged leptons and a neutrino •  All possible combina;ons of e, μ, τ simulated with LSP BRs varying among 4 extreme cases (l = e, μ):

at least 4 light leptons

at least 2 light leptons

6

(100%) (100%)

(50%)

(50%)

(50%)

(50%)

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(

0

0.1

0.2

0.3

0.4

0.53ikλ = -i3kλ

ν-l+ l→ 0

1χ∼

ν

±

τ± l→ 01χ∼

ijkλ

ν-l+ l→ 0

1χ∼

3i3λ = -i33λ

ν

±

τ± l→ 01χ∼

ν-τ+τ → 01χ∼

ij3λ

ν

±

τ± l→ 01χ∼

GluinoELL {1,2}∈i,j,k

Models: LLE terms

•  Simplified model: neutralino LSP decays into two charged leptons and a neutrino •  All possible combina;ons of e, μ, τ simulated with LSP BRs varying among 4 extreme cases (l = e, μ):

7

(100%) (100%)

(50%)

(50%)

(50%)

(50%)

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•  Each simulated LLE and LQD sample is generated with a fixed mass ra;o:

•  R determines how the available energy is shared between the final-‐state objects

Lower R souer LSP decay products more energe;c par;cles from the NLSP decays

•  May affect the choice of the best-‐performing signal region for a given model.

Results on LLE

•  Lower limits on the gluino mass for R=0.9, set from: •  4L analysis (SR0noZb: at least 4 light leptons): strongest limits: m(g̃) > 1350 GeV •  SS/3L analysis (SR3Lhigh: at least 3 light leptons): weaker limits: m(g̃) > 1140 GeV •  Combina;on 4L + SS/3L •  Limits weaken as the number of light leptons per event decreases

)RτBR(0 0.2 0.4 0.6 0.8 1

) LτBR

(

0

0.1

0.2

0.3

0.4

0.5

SS3Lboth

4L

ATLAS Preliminary

-1 = 8 TeV, 20.3 fbs ν-l+ l→ 01χ∼ 0

1χ∼qq0

1χ∼ qq→ g~g~ →pp

) = 0.9g~) / m(01χ∼m(

GluinoELL

Obs

erve

d M

ass

Exclu

sion

[GeV

]

1150

1200

1250

1300

1350

)RτBR(0 0.2 0.4 0.6 0.8 1

) LτBR

(

0

0.1

0.2

0.3

0.4

0.5

ATLAS Preliminary

-1 = 8 TeV, 20.3 fbs ν-l+ l→ 01χ∼ 0

1χ∼qq0


) = 0.9g~) / m(01χ∼All limits at 95% CL m(

GluinoELL

8

ATLAS-‐CONF-‐2015-‐018


•  Cases R=0.1, 0.5 similar results, see backup.

)τBR(0 0.1 0.2 0.3 0.4 0.5

BR(b

)

0

0.2

0.4

0.6

0.8

1ij3' λ

qb± l→ 01χ∼

qbν → 01χ∼

ijk' λqq'± l→ 0

1χ∼

qq'ν → 01χ∼

3j3' λqb±τ → 0

1χ∼

qbν → 01χ∼

3jk' λqq'±τ → 0

1χ∼

qq'ν → 01χ∼

SquarkD Gluino, LQDLQ {1,2}∈i,j,k

9

(50%) (50%)

(50%)

(50%)

(50%)

(50%)

(50%) (50%)

•  2 Simplified models: LQD gluino; LQD squark: neutralino LSP decays into two quarks and a lepton

•  A specific λ’ijk allows and

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Models: LQD terms

•  All possible combina;ons of e, μ, τ simulated with LSP BRs varying among 4 extreme cases:

)τBR(0 0.1 0.2 0.3 0.4 0.5

BR(b

)

0

0.2

0.4

0.6

0.8

1

0L 7-10 jetsj50

j50 + j80

ATLAS Preliminary

-1 = 8 TeV, 20.3 fbs qq ν l/→ 01χ∼ 0

1χ∼qq0


) = 0.5g~) / m(01χ∼m(

GluinoDLQ

Obs

erve

d M

ass

Exclu

sion

[GeV

]

102010401060108011001120114011601180120012201240

)τBR(0 0.1 0.2 0.3 0.4 0.5

BR(b

)

0

0.2

0.4

0.6

0.8

1

ATLAS Preliminary

-1 = 8 TeV, 20.3 fbs qq ν l/→ 01χ∼ 0

1χ∼qq0



GluinoDLQ

•  Model nominally produces 8 jets ! strongest constraints for R=0.1, 0.5 set by 0L + 7-‐10 jets analysis: m(g̃) > 1180 GeV •  Sta;s;cal combina;on of SR with/without b-‐jets ! mass limits shows dependence on BR(b) •  Veto on light leptons ! weaker limits in low BR(τ)

•  R=0.9: compressed SUSY spectrum ! 0L + 7-‐10 no longer produces best results. •  More powerful results for 1L and 0L + 2-‐6 jets analyses. See backup. 10

Results on LQD gluino ATLAS-‐CONF-‐2015-‐018


R=0.5

Obs

erve

d M

ass

Exclu

sion

[GeV

]

9209409609801000102010401060108011001120

)τBR(0 0.1 0.2 0.3 0.4 0.5

BR(b

)

0

0.2

0.4

0.6

0.8

1

ATLAS Preliminary

-1 = 8 TeV, 20.3 fbs qq ν l/→ 01χ∼ 0

1χ∼q0

1χ∼ q→ q~q~ →pp

) = 0.5q~) / m(01χ∼All limits at 95% CL m(

SquarkDLQ

)τBR(0 0.1 0.2 0.3 0.4 0.5

BR(b

)

0

0.2

0.4

0.6

0.8

1

1L both

0L 2-6 jets6jt+

ATLAS Preliminary

-1 = 8 TeV, 20.3 fbs qq ν l/→ 01χ∼ 0

1χ∼q0


) = 0.5q~) / m(01χ∼m(

SquarkDLQ

•  Model nominally produces 6 jets ! strongest constraints set by: •  1L for BR(τ) < 0.1: m(g̃) > 1120 GeV •  0L + 2-‐6 jets analysis for BR(τ) > 0.3: m(g̃) > 1050 -‐ 920 GeV •  combina;on of both in BR(τ) = (0.1, 0.3): m(g̃) > 1060 – 980 GeV

•  No dependency on BR(b) since neither analysis requires/vetoes on b-‐jets. •  Similar result obtained for R=0.9 (see backup).

11

R=0.5

Results on LQD squark ATLAS-‐CONF-‐2015-‐018


)+ 1χ∼ b

→ 1t~

BR(

00.10.20.30.40.50.60.70.80.91

[GeV]µ

200 250 300 350 400 450 500 550 600

[GeV

]L,

3q~

m

400

500

600

700

800

900

1000

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1200 )+ 1χ∼ b

→ 1t~

BR(

00.10.20.30.40.50.60.70.80.91

ATLAS Preliminary

Natural bRPV pMSSM

•  ATLAS searches have set limits on mSUGRA bRPV: m(g) ≥ 1.35 TeV, comparable to RPC limits.

•  Here first ;me to explore bRPV Natural SUSY: •  t̃ and higgsinos mass < 1 TeV •  Other masses: less stringent constraints survive previous limits

•  phenomenological MSSM (pMSSM) compa;ble with: •  Observed Higgs mass •  Measurements of ν oscilla;ons •  Main produc;on processes: t̃ t̃ , χ0̃, χ±̃

•  Free parameters: •  μ (higgsino mass parameter) •  mq̃L,3 (leu-‐ handed top and boDom squarks mass ! light for naturalness).

•  See further details in backup.

t1 b l ~

t1 t χ01,2

~ ~

t1̃ b χ± 1,2 ~

t1 = LSP ~

Models: bRPV terms

12

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˜ χ 1± → lbb ≈ 60%

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large lepton and b-‐jet mul;plicity

~

χ0, χ± masses increase ~ ~


Results on bRPV

[GeV]µ420 440 460 480 500 520 540 560

[GeV

]L,

3q~

m

650

700

750

800

850

900

950 = 1.7 TeVgluino, mµ = 32 = 30, MβNatural bRPV pMSSM: tan

)theorySUSYσ1 ±Observed limit (

)expσ1 ±Expected limit (

All limits at 95% CL

(450

GeV

)0 1χ∼

(500

GeV

)0 1χ∼

(550

GeV

)0 1χ∼

(550 GeV)1t~

(560 GeV)1t~

(570 GeV)1t

~

(580 GeV)1t

~

(580 GeV)1t~

(570 GeV)1t~

(560 GeV)1t~

(550 GeV)1t

~

) + m(t)±

1χ∼

) < m(1b~m(

decays1t~RPV

ATLAS Preliminary = 8 TeVs, -1 L dt = 20.3 fb∫

)theorySUSYσ1 ±Observed limit (

)expσ1 ±Expected limit (

All limits at 95% CL

13

•  Strongest constraints set by SR3b in the SS/3L analysis along the en;re plane. •  Limit weakens as mq̃L,3 increases due to:

•  Contribu;on from b"1 pair produc;on is cri;cal: large meff difficult to produce from t1̃ decays when t1̃ and χ±̃1 degenerate •  Increasing b"1 mass, and corresponding decrease in the b"1 b"1 produc;on cross-‐sec;on.

•  For mq̃L,3 = 800 GeV, en;re range of μ excluded.

•  Lower limits of μ < 455 GeV and mq̃L,3 > 810 GeV within explored region.

ATLAS-‐CONF-‐2015-‐018


14

eμ, eτ, μτ resonances


Heavy resonances

•  Aiming RPV combined LLE + LQD terms •  Selec;on:

•  Trigger on 1 or 2 leptons (e or μ) •  0 or 1 τhad candidates with 1 prong •  Exactly 2 leptons with OSDF •  Leptons back to back (Δϕ > 2.7) •  mll > 200 GeV (mll < 200 GeV used as VR)

•  Main backgrounds: •  2 prompt leptons:

Z/γ* -‐> ττ, Dbar, st Wt channel, dibosons Es;mated using MC

•  Jets misiden;fied as leptons (fakes): W+ jets, mul;jets Es;mated normalizing MC to data in CRs

•  Good agreement between expected and observed events in VRs and in SRs. 15

Phys. Rev. LeD. 115, 031801 (2015)

Even

ts /

20 G

eV

1−10

1

10

210

310

410

510 Data (1 TeV)τν

∼

ττ →Z Others

Z' (0.75 TeV)Jet fakettTotal SM

-1 = 8 TeV, 20.3 fbsATLAS

µe

Dilepton Mass [GeV]0 200 400 600 800 1000 1200Da

ta/S

M

12

•  Dedicated search for the decay of a heavy neutral par;cle into a pair of different flavor leptons via LFV couplings.


Models: LQD + LLE terms

16

•  Simplified model: tau sneutrino (ν̃τ) LSP decays to eμ, eτ, μτ

•  In this case RPV couplings are present both at the produc;on and at the decay vertex.

•  Only tau sneutrino is considered here in order to compare with previous searches performed at the Tevatron, but... •  The results of this analysis apply to any sneutrino flavour.


Results on LLE + LQD

17

[GeV]τν∼m

500 1000 1500 2000 2500 3000)[

fb]

τµ/τ

/eµ

BR

(e×

σ 1

10

210

310

410

-1 = 8 TeV, 20.3fbsATLASµ e→ τν∼

[GeV](Z')τν∼m

500 1000 1500 2000 2500 3000

)[fb

]τ

µ/τ/e

µ B

R(e

× σ

1−10

1

10

210

310

410 µ e→Z' [GeV]τν∼m

500 1000 1500 2000 2500 3000

)[fb

]τ

BR

(e×

σ

1

10

210

310

410

Theory

95% CL Observed limit

95% CL Expected limit

σ1 ±95% CL Expected limit


τ e→ τν∼

[GeV](Z')τν∼m

500 1000 1500 2000 2500 3000

)[fb

]τ

BR

(e×

σ

1−10

1

10

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410τ e→Z' [GeV]

τν∼m

500 1000 1500 2000 2500 3000

)[fb

]τµ

BR

(×

σ

1

10

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410

τµ → τν∼

[GeV](Z')τν∼m

500 1000 1500 2000 2500 3000

)[fb

]τµ

BR

(×

σ

1−10

1

10

210

310

410τµ →Z'

[GeV]τν∼m

500 1000 1500 2000 2500 3000

)[fb

]τ

µ/τ/e

µ B

R(e

× σ 1

10

210

310

410

-1 = 8 TeV, 20.3fbsATLASµ e→ τν∼

[GeV](Z')τν∼m

500 1000 1500 2000 2500 3000

)[fb

]τ

µ/τ/e

µ B

R(e

× σ

1−10

1

10

210

310

410 µ e→Z' [GeV]τν∼m

500 1000 1500 2000 2500 3000

)[fb

]τ

BR

(e×

σ

1

10

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410

Theory

95% CL Observed limit

95% CL Expected limit



τ e→ τν∼

[GeV](Z')τν∼m

500 1000 1500 2000 2500 3000

)[fb

]τ

BR

(e×

σ

1−10

1

10

210

310

410τ e→Z' [GeV]

τν∼m

500 1000 1500 2000 2500 3000

)[fb

]τµ

BR

(×

σ

1

10

210

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410

τµ → τν∼

[GeV](Z')τν∼m

500 1000 1500 2000 2500 3000

)[fb

]τµ

BR

(×

σ

1−10

1

10

210

310

410τµ →Z'

•  Theore;cal predic;ons of σ x BR: assuming λ’311 = 0.11 and λi3k = 0.07 •  Lower limits on the ν̃τ mass are 2.0 TeV, 1.7 TeV, and 1.7 TeV for eμ, eτ and μτ channels.

•  The observed lower mass limits are a factor of 3 – 4 higher than the best limits from the Tevatron and also more stringent than the previous limits from ATLAS for the same couplings.

Phys. Rev. LeD. 115, 031801 (2015)

Emma Torró SUSY15 Lake Tahoe, 28 Aug. 2015 •  Not a reinterpreta;on! Dedicated search for this model

Summary

18

•  R-‐parity viola;on can be a cause of non-‐discovery in general searches for new physics at LHC. •  A variety of RPV scenarios are tested either by dedicated searches or by reinterpre;ng previously published ATLAS searches.

•  LLE and LQD cases: •  Limits on produc;on cross-‐sec;on and spar;cle masses obtained for different LSP mass hypotheses as a func;on of the LSP BRs to boDom quarks and tau leptons.

•  Bilinear R-‐parity viola;on in natural pMSSM: •  Reinterpreta;on of previous ATLAS searches (SS/3L dominant) •  μ = (160, 455) GeV excluded at 95%CL; mq̃L,3 = 800 GeV excluded up to μ = 560 GeV •  Limits in natural SUSY with bRPV complement previous studies of mSUGRA model.

LLE LQD gg qq

LLE + LQD

Dominant analysis SS/3L 1L / 0L 1L / 0L eμ, eτhad, μτhad

mass limit m(g̃) > 1040 – 1400 GeV

m(g̃) > 910 -‐ 1220 GeV

R > 0.1: m(g̃) > 910 -‐ 1280 GeV

m(ν̃τ) > (2.0, 1.7, 1.7) TeV for (eμ, eτ, μτ)

reinterpreta;on of previous ATLAS searches dedicated ATLAS search


19

Backup


Search method

20 Emma Torró SUSY15 Lake Tahoe, 28 Aug. 2015

[GeV]effm

0 200 400 600 800 1000 1200 1400

Eve

nts

/ 2

50

Ge

V

-210

-110

1

10

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310

= 8 TeVs-1

L dt = 20.3 fb∫ATLAS Data 2012 Total SM

Reducible ZZ

Ztt tWZ

Higgs VVV

)=(600,400) GeV0

1χ∼,±

1χ∼0, m(≠121λ,

-

1χ∼

+

1χ∼

SR0noZb

•  Aiming RPC and RPV with LLE terms

•  Selec;on: •  ≥ 4 leptons (at least two of them e or μ) •  Veto on Z-‐>ll (orthogonal SRs contain Zs) •  No jet selec;on: valid for strong and EW

•  3 SRs relevant for LLE:

Four leptons (4L)

21

Phys. Rev. D. 90, 052001 (2014)

•  Good agreement between expected and observed events in VRs and in SRs.

•  Final result: sta;s;cal combina;on of all considered SRs.

• Main backgrounds: •  DZ, ZZ Es;mated from MC •  Non-‐prompt and fake leptons Es;mated with data driven methods, checked in VRs

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g̃

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p

p

q q

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q q

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•  Aiming RPC models where Majorana par;cle pairs decay semileptonically .

•  Selec;on: •  2 SS leptons OR 3 leptons •  3 relevant SRs:

•  Final result: sta;s;cal combina;on of all considered SRs.

2 same sign leptons / 3 leptons (SS/3L)

•  Main backgrounds: •  Prompt leptons:

DW, DZ (dominant in SRb), WW, WZ, ZZ + jets (dominant in SRL) Es;mated from MC

•  Fake leptons, charge-‐flip Es;mated with data-‐driven method [GeV]effm

200 400 600 800 1000 1200 1400

Eve

nts

/ 6

55 G

eV

1

2

3

4

5

6

7 ATLAS

= 8 TeVs, -1

L dt = 20.3 fb∫

SR3b Region

Data

SM Total

Fake leptons

Charge flip

Top + X

Diboson + Triboson

productiong~-g

~

bs (RPV)→1

t~

t, 1

t~ →g

~

) = (945, 417) GeV1

t~

, g~(

22

JHEP 06 (2014) 035

g̃ t t̃1

t χ̃01 gluino-mediated top squark → t χ̃0

1

b χ̃±1W±(∗) χ̃0

1 gluino-mediated top squark → b χ̃±1

c χ̃01 gluino-mediated top squark → c χ̃0

1

b s gluino-mediated top squark → b s (RPV)

g̃ q q̃(∗)

q̃ q′ χ̃±1

W±(∗)χ̃02

Z(∗)χ̃01 gluino-mediated (or direct) squark → q′ W Z χ̃0

1

W±(∗)χ̃01 gluino-mediated squark → q′W χ̃0

1

l̃±ν, l±ν̃

l̃l, ν̃νgluino-mediated (or direct) squark → sleptons

g̃ q q̃(∗)

q̃ q χ̃02

b̃1 t χ̃±1

W±(∗)χ̃01 direct bottom squark → t χ̃±

1

•  Good agreement between expected and observed events in SRs.


[GeV]TmissE

250 300 350 400 450 500 550Ev

ents

/ 10

0 G

eV0

5

10

15

20

25ATLAS

-1=8 TeV, 20.3 fbsµhard 1L e/

6-jet SR

DataStandard ModelTop QuarksV+jetsFake LeptonsDibosons

)=01χ∼, ±

1χ∼, g~ 1-step, m(g~g~

(1025, 545, 65) GeV

One lepton (1L) •  Aiming a wide variety of models (mSUGRA bRPV among them) with 1L or 2L OS. Here only 1L.

•  Selec;on: •  1L + jets •  3 relevant SRs:

•  Main backgrounds: •  Dbar and W+jets MC normalized to data in CRs with lower met, mT cuts Extrapola;on to SRs tested in VRs

23

Phys. Rev. LeD. 114, 161801 (2015)

•  Good agreement between expected and observed events in SRs.


0 leptons + 2-‐6 jets (0L + 2-‐6 jets)

•  Selec;on: •  no isolated leptons •  4 relevant SR with diff. jet mul;plicity :

>=5 jets with pT>60 GeV, at least one jet with pt>160 GeV

24

JHEP 09 (2014) 176

•  Aiming a variety of RPC with no leptons in the final state

(incl.) [GeV]effm0 500 1000 1500 2000 2500 3000 3500 4000

Even

ts /

100

GeV

1

10

210

-1L dt = 20.3 fb∫ = 8 TeV)sData 2012 (

SM Total)=3050

1χ∼

)=385,m(±1χ∼

)=465,m(q~ m(q~q~

)=62501χ∼

)=945,m(±1χ∼

)=1265,m(g~ m(g~g~

Multi-jetsW+jets(+X) & single toptt

Z+jetsDiboson

ATLASSR - 6jt+

t+ t+

(incl.) [GeV]effm0 500 1000 1500 2000 2500 3000 3500 4000

Dat

a / M

C

00.5

11.5

22.5

•  Main backgrounds •  W+jets , combined Dbar + single top, Z(-‐>nunu) + jets and mul;jets . Normalize MC to data in 4 CRs per SR. Checked in several VRs


•  Aiming RPC models and RPV with BNV

•  Selec;on: •  No isolated leptons •  13 relevant SRs with different jet and b-‐jet mul;plicity:

•  Main backgrounds: •  mul;jets Es;mated using matrix method •  Dbar and W+jets Normalize MC to data in 1 CR per SR •  Z+jets, DV, st Es;mated using MC

25

0 leptons + 7-‐10 jets (0L + 7-‐10 jets) J. High Energy Phys. 10 (2013) 130

g̃

g̃

�̃01

�̃01

p

p

q q

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q

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V

-210

-110

1

10

210

310

410

510

610Data

Total background

Multi-jets

ql,ll→ ttSingle top

+W, Ztt + b-jetsν l→W

+ light jetsν l→W

, ll + jetsνν →Z

]:[900,150] [GeV]1

0χ∼,g~[

ATLAS

=8 TeVs, -1L dt = 20.3 fb∫ 50 GeV≥

T 10 jets, p≥

340 GeV≥ ΣJM

]1/2 [GeVTH/missTE

0 2 4 6 8 10 12 14 16D

ata

/Pre

dic

tion

00.5

11.5

2


) 1bl + m0

bl)/(m1

bl - m0bl

(m0 0.2 0.4 0.6 0.8 1

Entri

es/0

.05

-110

1

10

210

310

Total backgroundtt

*γZ/Single topOtherB-L stop (500 GeV)B-L stop (800 GeV)B-L stop (1000 GeV)

ATLAS Simulation Preliminary

-1 = 8 TeV, 20.3 fbs

b

b̄

`+

`�

p

p

t̃

t̃⇤

�0

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26

B-‐L analysis descrip;on ATLAS-‐CONF-‐2015-‐015

[GeV] 0bl m

0 200 400 600 800 1000 1200

Entri

es/5

0 G

eV

-210

-110

1

10

210

310Total backgroundtt

*γZ/Single topOtherB-L stop (500 GeV)B-L stop (800 GeV)B-L stop (1000 GeV)

ATLAS Simulation Preliminary

-1 = 8 TeV, 20.3 fbs

•  Search for a peak in the invariant mass distribu;on of (two pairs of) bl

•  Impose a U(1)B-‐L symmetry to the SM with right-‐handed neutrinos •  Symmetry is spontaneously broken by right-‐handed sneutrino vev •  Simplified model with stop (LSP) pair produc;on

•  Selec;on: •  2 OS leptons (e, μ) + 2 bjets (no ETmiss cut!) + Z veto •  Check mbl asymmetry for all possible combina;ons of bl •  Take the combina;on with smallest mbl asymmetry •  Two SRs defined for high sensi;vity to different stop masses

•  Signal: small mbl •  SM bkg: flat mbl


b

b̄

`+

`�

p

p

t̃

t̃⇤

�0

�0

•  Main backgrounds: •  Dbar and Z+jets Normalize MC to data in CRs •  others Es;mated using MC

•  Good agreement between data and SM expecta;ons in all VRs and SRs

27

B-‐L analysis results ATLAS-‐CONF-‐2015-‐015

VR Top 1VR Top 1 (ee)

VR Top 1 (mm)

VR Top 1 (em)


VR Top 2 (mm)

VR Top 2 (em)


VR Top 3 (mm)

VR Top 3 (em)

VR Z VR Z (ee)VR Z (mm)

Num

ber o

f eve

nts

1

10

210

310

410

510

ATLAS Preliminary -1 = 8 TeV, 20.3 fbsDatatt

*γZ/Single topOther


VR Top 1 (mm)

VR Top 1 (em)


VR Top 2 (mm)

VR Top 2 (em)


VR Top 3 (mm)

VR Top 3 (em)

VR Z VR Z (ee)VR Z (mm)

tot

σ) /

pr

ed -

nob

s(n -2

0

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•  Limits set on the stop mass range (1.1, 0.5) TeV


Obs

erve

d M

ass

Exclu

sion

[GeV

]

1050

1100

1150

1200

1250

1300

1350

)RτBR(0 0.2 0.4 0.6 0.8 1

) LτBR

(

0

0.1

0.2

0.3

0.4

0.5

ATLAS Preliminary

-1 = 8 TeV, 20.3 fbs ν-l+ l→ 01χ∼ 0

1χ∼qq0



GluinoELL

Further results on LLE

28

R=0.1

Emma Torró SUSY15 Lake Tahoe, 28 Aug. 2015 O

bser

ved

Mas

s Ex

clusio

n [G

eV]

1200

1250

1300

1350

1400

)RτBR(0 0.2 0.4 0.6 0.8 1

) LτBR

(

0

0.1

0.2

0.3

0.4

0.5

ATLAS Preliminary

-1 = 8 TeV, 20.3 fbs ν-l+ l→ 01χ∼ 0

1χ∼qq0



GluinoELL

Obs

erve

d M

ass

Exclu

sion

[GeV

]

1150

1200

1250

1300

1350

)RτBR(0 0.2 0.4 0.6 0.8 1

) LτBR

(

0

0.1

0.2

0.3

0.4

0.5

ATLAS Preliminary

-1 = 8 TeV, 20.3 fbs ν-l+ l→ 01χ∼ 0

1χ∼qq0



GluinoELL

R=0.5 R=0.9

)RτBR(0 0.2 0.4 0.6 0.8 1

) LτBR

(

0

0.1

0.2

0.3

0.4

0.5

SS3Lboth

4L

ATLAS Preliminary

-1 = 8 TeV, 20.3 fbs ν-l+ l→ 01χ∼ 0

1χ∼qq0


) = 0.9g~) / m(01χ∼m(

GluinoELL

limits driven by the SS/3L analysis

)τBR(0 0.1 0.2 0.3 0.4 0.5

BR(b

)

0

0.2

0.4

0.6

0.8

1

1L

both0L 2-6 jets

6jt+

ATLAS Preliminary

-1 = 8 TeV, 20.3 fbs qq ν l/→ 01χ∼ 0

1χ∼qq0


) = 0.9g~) / m(01χ∼m(

GluinoDLQ

29

Further results on LQD gluino ATLAS-‐CONF-‐2015-‐018


Obs

erve

d M

ass

Exclu

sion

[GeV

]920

940

960

980

1000

1020

1040

)τBR(0 0.1 0.2 0.3 0.4 0.5

BR(b

)

0

0.2

0.4

0.6

0.8

1

ATLAS Preliminary

-1 = 8 TeV, 20.3 fbs qq ν l/→ 01χ∼ 0

1χ∼qq0



GluinoDLQ

Obs

erve

d M

ass

Exclu

sion

[GeV

]

102010401060108011001120114011601180120012201240

)τBR(0 0.1 0.2 0.3 0.4 0.5

BR(b

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0

0.2

0.4

0.6

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ATLAS Preliminary

-1 = 8 TeV, 20.3 fbs qq ν l/→ 01χ∼ 0

1χ∼qq0



GluinoDLQ

Obs

erve

d M

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sion

[GeV

]

1080

1100

1120

1140

1160

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1200

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BR(b

)

0

0.2

0.4

0.6

0.8

1

ATLAS Preliminary

-1 = 8 TeV, 20.3 fbs qq ν l/→ 01χ∼ 0

1χ∼qq0



GluinoDLQ

)τBR(0 0.1 0.2 0.3 0.4 0.5

BR(b

)

0

0.2

0.4

0.6

0.8

1

0L 7-10 jetsj50

j50 + j80

ATLAS Preliminary

-1 = 8 TeV, 20.3 fbs qq ν l/→ 01χ∼ 0

1χ∼qq0


) = 0.5g~) / m(01χ∼m(

GluinoDLQ

)τBR(0 0.1 0.2 0.3 0.4 0.5

BR(b

)

0

0.2

0.4

0.6

0.8

1

0L 7-10 jetsj80

ATLAS Preliminary

-1 = 8 TeV, 20.3 fbs qq ν l/→ 01χ∼ 0

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) = 0.1g~) / m(01χ∼m(

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R=0.1 R=0.5 R=0.9

Obs

erve

d M

ass

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sion

[GeV

]

9209409609801000102010401060108011001120

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)

0

0.2

0.4

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) = 0.5q~) / m(01χ∼m(

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erve

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BR(b

)

0

0.2

0.4

0.6

0.8

1

ATLAS Preliminary

-1 = 8 TeV, 20.3 fbs qq ν l/→ 01χ∼ 0

1χ∼q0



SquarkDLQ

)τBR(0 0.1 0.2 0.3 0.4 0.5

BR(b

)

0

0.2

0.4

0.6

0.8

1

1L both0L 2-6 jets

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ATLAS Preliminary

-1 = 8 TeV, 20.3 fbs qq ν l/→ 01χ∼ 0

1χ∼q0


) = 0.9q~) / m(01χ∼m(

SquarkDLQ

30

Further results on LQD squark ATLAS-‐CONF-‐2015-‐018


R=0.5 R=0.9

•  and masses increase with μ. •  μ>570 GeV ! LPS = t1̃ ! Different phenomenology, not considered here

Exploring bRPV in pMSSM

31

[GeV]L,3

q~m200 400 600 800 1000 1200 1400 1600

m [G

eV]

400

600

800

1000

1200

1400

1600

ATLAS Preliminary

)1b~mass()1t

~mass()2t

~mass(

)+ 1χ∼ b

→ 1t~

BR(

00.10.20.30.40.50.60.70.80.91

[GeV]µ

200 250 300 350 400 450 500 550 600

[GeV

]L,

3q~

m

400

500

600

700

800

900

1000

1100

1200 )+ 1χ∼ b

→ 1t~

BR(

00.10.20.30.40.50.60.70.80.91

ATLAS Preliminary

Natural bRPV pMSSM

t1 < 600 GeV bounded by μ

€

˜ χ 1,20

€

˜ χ 1±

~

t1 b l ~

t1 t χ01,2

~ ~

t1 b χ± 1,2

~ ~

t1 = LSP ~

•  Complex phenomenology, discussed for the first ;me in RPV summary paper: ATLAS-‐CONF-‐2015-‐018 •  m( , ) vary with mq̃L,3, almost independent of μ.

€

˜ t

€

˜ b


χ0, χ± masses increase

•  other regions: more compressed spectrum reduces the momentum of par;cles from the t1̃ and b"1 decays and increases signal contamina;ng the valida;on regions of the SS/3L analysis

•  Interes;ng region around μ = 550 GeV and mqL,3 = 800 GeV: • m(t1̃) ≈ m(χ±̃1) ≈ m(χ̃01). • 


32

)+ 1χ∼ b

→ 1t~

BR(

00.10.20.30.40.50.60.70.80.91

[GeV]µ

200 250 300 350 400 450 500 550 600

[GeV

]L,

3q~

m

400

500

600

700

800

900

1000

1100

1200 )+ 1χ∼ b

→ 1t~

BR(

00.10.20.30.40.50.60.70.80.91

ATLAS Preliminary

Natural bRPV pMSSM takes largest mass available for natural pMSSM scenario (m(t ) ︎ < 580 GeV). < 580 GeV). Maximum possible Δm( , LSP)

€

˜ t 1

€

˜ t 1

•  neutralino LSP •  t1̃ b χ±̃1,2 kinema;cally accessible to avoid discon;nui;es in the spar;cle decay paDerns

t1̃ b χ±̃1,2


100% ~


33

•  Search channels requiring at least one lepton are used to constrain the natural bRPV model. •  The lepton requirement is mo;vated by the high branching ra;os of the χ01 and χ±1 to leptons, together with the possibility of addi;onal leptons from RPC SUSY cascades.

•  L1 search: too ;ght met cut ! low sensi;vity BUT •  Since neutralino LSP is majorana! two LSP can decay to SS leptons st1 = LSP

t̃

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1000

1100

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ATLAS Preliminary

Natural bRPV pMSSM

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)±

W± l→ 0 1χ∼

BR(

00.10.20.30.40.50.60.70.80.91

[GeV]µ

200 250 300 350 400 450 500 550 600

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m

400

500

600

700

800

900

1000

1100

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W± l→ 0 1χ∼

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00.10.20.30.40.50.60.70.80.91

ATLAS Preliminary

Natural bRPV pMSSM


GGM1.5 SRee# - CERNR BR(τ 0 0.2 0.4 0.6 0.8 1) L τ BR(0 0.1 0.2 0.3 0.4 0.5 λ i3k = -λ 3ik 0 →...

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Transcript of GGM1.5 SRee# - CERNR BR(τ 0 0.2 0.4 0.6 0.8 1) L τ BR(0 0.1 0.2 0.3 0.4 0.5 λ i3k = -λ 3ik 0 →...