Measurement of cross sections and properties of the Higgs boson in - - PowerPoint PPT Presentation

SLIDE 1

Measurement of cross sections and properties of the Higgs boson in decays to bosons with the ATLAS experiment

Lake Louise Winter Insitute 2019 Ruggero Turra

• n behalf of the ATLAS Collaboration

INFN Milano

11 February, 2019

SLIDE 2

References for Run2 13 TeV 36 fb−1 and 80 fb−1

Latest Summer Run 2 results with 80 fb−1 13 TeV: H → γγ: ATLAS-CONF-2018-028 H → 4ℓ: ATLAS-CONF-2018-018

combination γγ + 4ℓ + eνµν + ττ + VH(bb) + µµ + ttH(bb and multilepton): ATLAS-CONF-2018-031 combination ttH γγ + 4ℓ + bb + multilepton (5.8σ):

• Phys. Lett. B 784 (2018) 173

Latest Run 2 results with 36 fb−1 13 TeV: Mass γγ+4ℓ: Phys. Lett. B 784 (2018) 345 xsections combination γγ+4ℓ: Phys. Lett. B 786

(2018) 114

H → γγ: Phys. Rev. D 98 (2018) 052005 H → 4ℓ: JHEP 03 (2018) 095 EFT interpretation γγ+4ℓ:

ATL-PHYS-PUB-2017-018

H → WW → eνµν: Phys. Lett. B 789 (2019) 508

Month in Year Jan '15 Jul '15 Jan '16 Jul '16 Jan '17 Jul '17 Jan '18 Jul '18

• 1

fb Total Integrated Luminosity 20 40 60 80 100 120 140 160 80 fb-1 ATLAS Preliminary

LHC Delivered ATLAS Recorded = 13 TeV s

• 1

fb Delivered: 158

• 1

fb Recorded: 149

Initial 2018 calibration

36 fb-1 R.Turra (INFN Milano) Higgs to bosons (ATLAS) 11 February, 2019 2 / 27

SLIDE 3

Table of contents

1 Higgs boson and its properties 2 Decay channels (γγ, ZZ ∗ → 4ℓ, WW ∗ → eνµν) 3 Combination 4 Conclusions

R.Turra (INFN Milano) Higgs to bosons (ATLAS) 11 February, 2019 3 / 27

SLIDE 4

Higgs properties

Excess compatible with Higgs boson firmly established by ATLAS+CMS in 2012. Measurements Mass: mH known at 0.2% (single experiment) σ × Br: inclusive, for each production-mode, fiducial region (STXS), decay (strong SM assumption: very optimized analyses, acceptance extrapolations) Fiducial cross sections (minimal model dependence) Differential kinematic distributions for each decay in fiducial regions (minimal model dependence) Interpretations Spin and parity: 0+, other models excluded in Run 1 Signal strengths: µi = σi/σSM

i

, µf = BRf /BRSM

f

(inclusive, per-production-mode, . . . ) Coupling modifiers to SM particles (k-framework) EFT interpretations

R.Turra (INFN Milano) Higgs to bosons (ATLAS) 11 February, 2019 4 / 27

SLIDE 5

Higgs properties

Excess compatible with Higgs boson firmly established by ATLAS+CMS in 2012. Measurements Mass: mH known at 0.2% (single experiment) σ × Br: inclusive, for each production-mode, fiducial region (STXS), decay (strong SM assumption: very optimized analyses, acceptance extrapolations) Fiducial cross sections (minimal model dependence) Differential kinematic distributions for each decay in fiducial regions (minimal model dependence) Interpretations Spin and parity: 0+, other models excluded in Run 1 Signal strengths: µi = σi/σSM

i

, µf = BRf /BRSM

f

(inclusive, per-production-mode, . . . ) Coupling modifiers to SM particles (k-framework) EFT interpretations

R.Turra (INFN Milano) Higgs to bosons (ATLAS) 11 February, 2019 4 / 27

SLIDE 6

Simplified template cross sections (STXS) stage 1

Defined in the CERN Yellow Report 4 Exclusive fiducial regions defined by production mode, pH

T , Nj, VBF-topology, pj1 T ,

pHjj

T , pV T

STXS bins

interpr.

Design measurement to split events according to STXS

R.Turra (INFN Milano) Higgs to bosons (ATLAS) 11 February, 2019 5 / 27

SLIDE 7

γγ, ZZ ∗ → 4ℓ, WW ∗ → eνµν

BR/10−3

• sig. eff.

mass resolution Backgrounds γγ 2.27 42% 1.41–2.10 GeV Large: q¯ q/gg → γγ and fakes 4ℓ 0.124 24% 1.6–2.4 GeV Small: q¯ q/gg → ZZ ∗ and fakes eνµν 5.04 ∼ 11% Transverse mass q¯ q/gg → WW ∗, t¯ t, Wt, . . .

R.Turra (INFN Milano) Higgs to bosons (ATLAS) 11 February, 2019 6 / 27

SLIDE 8

H → γγ coupling

Decay with loop: can probe coupling to both fermions and vectors; sensitive to BSM Model large smooth background as a functional form, fitted on data Difficult to validate the potential bias on the signal: important systematics Lot of data: categorize the events in a fine way, targeting STXS Observable: diphoton mass, direction from calorimeter pointing

2 − 1 − 1 2 3 4 5

SM

x B) σ x B) / ( σ (

Total Stat. Syst. SM Preliminary ATLAS

−1

= 13 TeV, 79.8 fb s | < 2.5

H

, |y γ γ → H ( ) Total Stat. Syst. Top )

− 0.19 + 0.23 − 0.34 + 0.37

(

− 0.38 + 0.44

1.13 VH, leptonic )

− 0.25 + 0.29 − 0.59 + 0.65

(

− 0.64 + 0.71

1.38 Hqq, BSM−like → ggF + qq 0.23 ) ±

− 0.43 + 0.45

(

− 0.49 + 0.50

0.76 <200 GeV

j T

Hqq, 0<p → qq )

− 0.21 + 0.30 − 0.34 + 0.36

(

− 0.40 + 0.47

1.40 ggF, >= 2j )

− 0.21 + 0.29

0.47 ± (

− 0.52 + 0.56

0.65 <200 GeV

H T

ggF, 1j, 120<p )

− 0.35 + 0.49 − 0.68 + 0.70

(

− 0.76 + 0.85

1.51 <120 GeV

H T

ggF, 1j, 60<p )

− 0.21 + 0.27 − 0.42 + 0.43

(

− 0.47 + 0.50

0.89 <60 GeV

H T

ggF, 1j, 0<p )

− 0.31 + 0.43

0.52 ± (

− 0.61 + 0.68

1.23 ggF, 0j )

− 0.14 + 0.16

0.17 ± (

− 0.22 + 0.23

0.92

Difficult to separate

✞ ✝ ☎ ✆

ggF 0j/ggF 1j pT < 60 GeV and

✞ ✝ ☎ ✆

qq → Hqq/ggF 2j

R.Turra (INFN Milano) Higgs to bosons (ATLAS) 11 February, 2019 7 / 27

SLIDE 9

H → γγ coupling categorization

To measure many cross-sections with small correlation split events in pure categories

ggF ttH

prod modes

VH VBF

29 reco-categories inspired by STXS

R.Turra (INFN Milano) Higgs to bosons (ATLAS) 11 February, 2019 8 / 27

SLIDE 10

H → γγ cross sections

With 80 fb−1 unfolded (bin by bin) distribution for pγγ

T , yγγ, pj1 T , Nb−jets (lepton-veto)

50 100 150 200 250 300 350

2 −

10

1 −

10 1 [fb/GeV]

γ γ T

p / d

fid

σ d Preliminary ATLAS

• 1

= 13 TeV, 79.8 fb s , γ γ → H Data, tot. unc.

• Syst. unc.

XH default MC + H → gg bbH + ttH + VH = VBF+ XH XH SCET + ⊕ NNLOJET 50 100 150 200 250 300 350 [GeV]

γ γ T

p 1 2 XH Ratio to default MC +

1 2

20 40 60 80 | [fb]

γ γ

y / d|

fid

σ d Preliminary ATLAS

• 1

= 13 TeV, 79.8 fb s , γ γ → H data, tot. unc.

• syst. unc.

XH default MC + H → gg bbH + ttH + VH = VBF+ XH XH SCETlib+MCFM8 + H → gg 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 2.2 2.4 |

γ γ

y | 1 2 XH Ratio to default MC +

200

2 −

10

1 −

10 1 [fb/GeV]

j1 T

p / d

fid

σ d Preliminary ATLAS

• 1

= 13 TeV, 79.8 fb s , γ γ → H data, tot. unc.

• syst. unc.

XH default MC + H → gg bbH + ttH + VH = VBF+ XH XH NNLOJET + H → gg XH SCETlib (STWZ) + H → gg ≥

jets

N = 0.4, R

t

k anti 50 100 150 200 250 300 350 [GeV]

j1 T

p 1 2 XH Ratio to default MC +

1 2 3 4

2 −

10

1 −

10 1 10

2

10

3

10 [fb]

fid

σ Preliminary ATLAS

• 1

= 13 TeV, 79.8 fb s , γ γ → H data, tot. unc.

• syst. unc.

XH default MC + H → gg bbH + ttH + VH = VBF+ XH ttH = 0

µ e+

N 1, ≥ | < 2.5) η > 30 GeV, |

T

(p

jets

N = 0 = 1 2 ≥ b-jets

N 1 2 XH Ratio to default MC +

Define fiducial regions only with kinematic cuts, close to the ones used in the analysis: small model dependency. p-value(χ2) data/SM > 30% Can be used as input of EFT interpretation (36 fb−1): introduce additional CP-even and CP-odd interactions in SILH framework inputs: pγγ

T , Nj, mjj, |∆φjj|, pj1 T and

their correlations

HW

HB HW HW HB

c

c = c c = c

HW

c ~

~ ~

0.2 0.1 0.1 0.2 0.4 0.2 0.2 0.4

contours hold 68%, 95% CL γ γ

σ σ Δ

− − − −

⊕ ⊕ ⊕

= 125.09 GeV

H

, m

• 1

= 13 TeV, 36.1 fb s , γ γ → H Standard Model 68% CL 95% CL

R u n 1 9 5 % C L R u n 1 6 8 % C L

ATLAS

R.Turra (INFN Milano) Higgs to bosons (ATLAS) 11 February, 2019 9 / 27

SLIDE 11

H → ZZ → 4ℓ coupling

Very pure channel, but less statistics Correct the mass for FSR photons Largest backgrounds from MC, fakes data driven

2 4 6 8 10

SM

) B ⋅ σ /( B ⋅ σ

ttH

• Lep

VH

• Had

VH

• High

j T

p VBF-

• Low

j T

p VBF- j ggF-2

• High

H T

p

• j

ggF-1

• Med

H T

p

• j

ggF-1

• Low

H T

p

• j

ggF-1 j ggF-0

[fb] B ⋅ σ [fb]

SM

) B ⋅ σ (

(95% CL) < 60

1.6 − 1.1 +

15.4 25 ± 20

1.4 − 0.8 +

16.5 100 ± 20

3.3 − 1.9 +

35.9 25 ± 30

0.2 − 0.4 +

4.1 /3 95 ± 240 2.7 ± 87.2 110 ± 160 30 ± 140 27 ± 7 5 ± 24 55 ± 80 20 ± 120 105 ± 100 20 ± 170 165 ± 870 50 ± 720

ZZ* → H

• 1

13 TeV, 79.8 fb | < 2.5

H

Reduced Stage 1 - |y

ATLAS Preliminary

Expected SM Observed: Stat + Sys SM Prediction

1 − 0.8 − 0.6 − 0.4 − 0.2 − 0.2 0.4 0.6 0.8 1

j ggF-0

• Low

H T

p

• j

ggF-1

• Medium

H T

p

• j

ggF-1

• High

H T

p

• j

ggF-1 j ggF-2

• Low

j T

p VBF-

• High

j T

p VBF-

• Had

VH

• Lep

VH ttH ttH

• Lep

VH

• Had

VH

• High

j T

p VBF-

• Low

j T

p VBF- j ggF-2

• High

H T

p

• j

ggF-1

• Medium

H T

p

• j

ggF-1

• Low

H T

p

• j

ggF-1 j ggF-0

1.00

• 0.02
• 0.02
• 0.03
• 0.05
• 0.02

0.00

• 0.01
• 0.02

1.00 0.00

• 0.11
• 0.11
• 0.09
• 0.53

0.17 0.03 1.00 0.01 0.01 0.04

• 0.31
• 0.17

0.04 1.00

• 0.01
• 0.15
• 0.23
• 0.23
• 0.38

1.00

• 0.03

0.07

• 0.10

0.01 1.00 0.05 0.01 0.09 1.00 0.06

• 0.03

1.00

• 0.39

1.00 1.00

ATLAS Preliminary

4l → ZZ* → H

• 1

13 TeV, 79.8 fb

Use a reduced scheme due to limited statistics

R.Turra (INFN Milano) Higgs to bosons (ATLAS) 11 February, 2019 10 / 27

SLIDE 12

H → ZZ → 4ℓ coupling categorization

ggF

ttH VH-lep VBF

Categorization of the events with simple cuts that mimic STXS definitions For each region as observable use the output of BDT distributions. BDT using kinematic discrimintat (based on matrix elements) and other kinematic variables trained to remove ZZ ∗ background and ggF from other production modes. Main uncertainty from luminostiy and lepton efficiency

R.Turra (INFN Milano) Higgs to bosons (ATLAS) 11 February, 2019 11 / 27

SLIDE 13

H → WW → eνµν

Categorize by Nj, mℓℓ, psubl

T , (e/µ)subl

Use transverse mass (for ggF, i.e. 0,1 j) or BDT (for VBF i.e. 2j) as observable Background normalization from dedicated CR

BDT score

[-1,0.26] [0.26,0.61] [0.61,0.86] [0.86,1.0]

Events / bin 500 1000 1500 2000 2500

Data Uncertainty

VBF

H

ggF

H /Wt t t WW * γ Z/ Mis-Id VV

ATLAS

• 1

= 13 TeV, 36.1 fb s 2 VBF ≥

jet

N , ν µ ν e → WW* → H

Events/bin 50 100 150

process σ × BR SM prediction ggF 11.4+1.2

−1.1(stat.)−1.2 −1.1(theo syst.)+1.4 −1.3(exp. syst.) pb

10.4 ± 0.6 pb VBF 0.50+0.24

−0.22(stat.) ± 0.10(theo syst.)+0.12 −0.13(exp. syst.) pb

0.81 ± 0.02 pb Important systematics from theory uncertainty on WW background.

R.Turra (INFN Milano) Higgs to bosons (ATLAS) 11 February, 2019 12 / 27

SLIDE 14

Section 3 Combination γγ + 4ℓ + eνµν + ττ + VH(bb) + µµ + ttH(bb and multilepton)

SLIDE 15

Cross sections per production mode |yH| < 2.5

Cross-section normalized to SM value 0.5 − 0.5 1 1.5 2 2.5 3 3.5 4

Total Stat. Syst. SM Preliminary ATLAS

• 1

= 13 TeV, 36.1 - 79.8 fb s | < 2.5

H

= 125.09 GeV, |y

H

m Total Stat. Syst. ggF )

0.06 0.07

± ,

0.07 0.07

± (

0.09 0.09

± 1.07 VBF )

0.12 0.13

± ,

0.18 0.18

± (

0.21 0.22

± 1.21 WH )

0.32 0.37

± ,

0.35 0.37

± (

0.48 0.52

± 1.57 ZH )

0.24 0.25

± ,

0.32 0.34

± (

0.40 0.42

± 0.74 ttH + tH )

0.18 0.20

± ,

0.17 0.17

± (

0.25 0.26

± 1.22 ggF

σ

VBF

σ

WH

σ

ZH

σ

ttH + tH

σ

ttH + tH

σ

ZH

σ

WH

σ

VBF

σ

ggF

σ (X,Y) ρ 1 − 0.8 − 0.6 − 0.4 − 0.2 − 0.2 0.4 0.6 0.8 1

0.07

• 0.02
• 0.07
• 0.14

1.00 0.03 0.01 0.02 1.00

• 0.02
• 0.09

1.00

• 0.01

1.00 1.00

Preliminary ATLAS

• 1

= 13 TeV, 36.1 - 79.8 fb s | < 2.5

H

= 125.09 GeV, |y

H

m

All the measurement still dominated by statistics Main correlation from the contamination ggF in VBF Br fixed to SM (with uncertainties)

[pb]

ggF

σ 10 20 30 40 50 60 70 80 90 100 [pb]

VBF

σ 5 10 15 20 Preliminary ATLAS

• 1

= 13 TeV, 36.1 - 79.8 fb s | < 2.5

H

= 125.09 GeV, |y

H

m ZZ → H γ γ → H WW → H τ τ → H Combined 68% CL 95% CL Best Fit SM

R.Turra (INFN Milano) Higgs to bosons (ATLAS) 11 February, 2019 14 / 27

SLIDE 16

k-framework interpretation (σ × BR)if = k2

i σSM i

× k2

f ΓSM f

k2

HΓSM H

In the simpler case only two modifiers: kV and kF, k2

H = k2 H(kV , kF)

• r with more modifiers: kµ, kτ, kt, kb, kW , kZ

V

κ 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2

F

κ 0.5 1 1.5 2 2.5 Preliminary ATLAS

1 −

= 13 TeV, 36.1 - 79.8 fb s | < 2.5

H

y = 125.09 GeV, |

H

m

Best fit 68% CL 95% CL SM

Combined γ γ → H ZZ → H WW → H bb → H τ τ → H

1 −

10 1 10

2

10 Particle mass [GeV]

4 −

10

3 −

10

2 −

10

1 −

10 1 v

V

m

V

κ

• r

v

F

m

F

κ

Preliminary ATLAS

1 −

= 13 TeV, 36.1 - 79.8 fb s | < 2.5

H

y = 125.09 GeV, |

H

m

µ τ b W Z t

SM Higgs boson

• r kg and kγ and BSM contributions

R.Turra (INFN Milano) Higgs to bosons (ATLAS) 11 February, 2019 15 / 27

SLIDE 17

Differential cross sections (pH

T and |yH|) with 36 fb−1 γγ+4ℓ

pH

T sensitive to pQCD, |yH| sensitive to PDF

0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 2.2 [pb/GeV]

T H

p /d σ d

l 4 → ZZ* → H Combined γ γ → H

• Syst. uncertainties

HRes + XH = 1.1) + XH K NNLOPS ( = 1.47) + XH K MG5 ( RadISH + XH XH = VBF+WH+ZH+ttH+bbH

ATLAS

γ γ → ZZ, H → H

• 1

13 TeV, 36.1 fb

10 20 30 45 60 80 120 200 350 [GeV]

H T

p

0.4 0.6 0.8 1 1.2 1.4 1.6 Theory/Data

10 20 30 40 50 60 70 [pb]

H

y /d σ d

l 4 → ZZ* → H Combined γ γ → H

• Syst. uncertainties

= 1.1) + XH K NNLOPS ( = 1.47) + XH K MG5 ( SCETlib + MCFM8 + XH XH = VBF+WH+ZH+ttH+bbH

ATLAS

γ γ → ZZ, H → H

• 1

13 TeV, 36.1 fb

0.3 0.6 0.9 1.2 1.6 2.5

H

y

0.4 0.6 0.8 1 1.2 1.4 1.6 Theory/Data R.Turra (INFN Milano) Higgs to bosons (ATLAS) 11 February, 2019 16 / 27

SLIDE 18

Differential cross sections (Nj and pj1

T ) with 36 fb−1 γγ+4ℓ

Nj and pj1

T sensitive to high-pT QCD radiation and to different production

modes

10 20 30 40 50 60 70 [pb] σ

l 4 → ZZ* → H Combined γ γ → H

• Syst. uncertainties

JVE + XH = 1.1) + XH K NNLOPS ( = 1.47) + XH K MG5 ( STWZ + XH XH = VBF+WH+ZH+ttH+bbH

ATLAS

γ γ → ZZ, H → H

• 1

13 TeV, 36.1 fb

1 2 1 ≥ 2 ≥ 3 ≥

jets

N

0.4 0.6 0.8 1 1.2 1.4 1.6 Theory/Data

0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 [pb/GeV]

j1 T

p /d σ d

l 4 → ZZ* → H Combined γ γ → H

• Syst. uncertainties

= 1.1) + XH K NNLOPS ( SCETlib (STWZ) + XH XH = VBF+WH+ZH+ttH+bbH

ATLAS

γ γ → ZZ, H → H

• 1

13 TeV, 36.1 fb

30 55 75 120 350 [GeV]

j1 T

p

0.4 0.6 0.8 1 1.2 1.4 1.6 Theory/Data R.Turra (INFN Milano) Higgs to bosons (ATLAS) 11 February, 2019 17 / 27

SLIDE 19

EFT interpretation from coupling STXS measurements with 36 fb−1 L = LSM +

• i

c(6)

i

O(6)

i

/Λ2 Six coefficients ¯ ci = ci/Λ in the SIHL basis related to STXS cross-sections

Parameter value

• 2

2

γ γ → ZZ* and H → Observed HEL constraints with H

• 1

= 13 TeV, 36.1 fb s

ATLAS Preliminary

]

• 4

cG [ 10 ]

• 4

cA [ 10 cu ]

• 1

cHW [ 10 ]

• 1

cHB [ 10 ]

• 1

cWW - cB [ 10

4l) → B(H ) γ γ → B(H ggF <25 GeV

3

j T

p Hqq → qq 25 GeV ≥

3

j T

p Hqq → qq VH-like Hqq → qq rest Hqq → qq >200 GeV

j T

p Hqq → qq

W T

low p ν Hl

W T

high p ν Hl

Z T

low p Hll

Z T

high p Hll H t t

Ratio with respect to SM 1 10 cG = 0.00003 cHW = 0.04 cA = 0.0003 cHB = 0.15 cu = 0.25 cWW - cB = 0.06

• 1

= 13 TeV, 36.1 fb s ATLAS Preliminary

Some correlations between parameters Good compatibility with SM (p-value 47%) Will add more measurements, larger set of operators

R.Turra (INFN Milano) Higgs to bosons (ATLAS) 11 February, 2019 18 / 27

SLIDE 20

Mass measurement γγ + 4ℓ with 36 fb−1 Hundreds of systematics on the energy/momentum scale of γ/e/µ Energy scale mostly from Z → ℓℓ (

• pℓ

T

• ≃ 40 GeV) comparing

data/MC

H → γγ (pγ

T ≃ 60 GeV) starts to be dominated by systematics

123 124 125 126 127 128 [GeV]

H

m

Total

• Stat. only

ATLAS

Total (Stat. only)

Run 1 ATLAS + CMS

0.21) GeV ± 0.24 ( ± 125.09

Combined Run 1+2

0.16) GeV ± 0.24 ( ± 124.97

Combined Run 2

0.18) GeV ± 0.27 ( ± 124.86

Combined Run 1

0.37) GeV ± 0.41 ( ± 125.38

γ γ → H Run 1+2

0.19) GeV ± 0.35 ( ± 125.32

l 4 → H Run 1+2

0.30) GeV ± 0.30 ( ± 124.71

γ γ → H Run 2

0.21) GeV ± 0.40 ( ± 124.93

l 4 → H Run 2

0.36) GeV ± 0.37 ( ± 124.79

γ γ → H Run 1

0.43) GeV ± 0.51 ( ± 126.02

l 4 → H Run 1

0.52) GeV ± 0.52 ( ± 124.51

• 1

= 13 TeV, 36.1 fb s : Run 2 ,

• 1

= 7-8 TeV, 25 fb s : Run 1 R.Turra (INFN Milano) Higgs to bosons (ATLAS) 11 February, 2019 19 / 27

SLIDE 21

Section 4 Conclusions

SLIDE 22

Conclusions Precision studies about Higgs boson from ATLAS have been presented: fiducial/differential cross sections, couplings, mass Preliminary results based on 80 fb−1, or 36 fb−1, using γγ, ZZ(4ℓ), WW (eνµν) decays More data ⇒ more measurements, more differential, more complicated interpretations (µ → ki → EFT/PO) No deviation from SM Now working on final Run2 papers with 140 fb−1

R.Turra (INFN Milano) Higgs to bosons (ATLAS) 11 February, 2019 21 / 27

SLIDE 23

SLIDE 24

Section 5 Backup

SLIDE 25

B normalized to SM value × σ

1 − 0.5 − 0.5 1 1.5 2 2.5 3 3.5 4

Preliminary ATLAS

• 1

= 13 TeV, 36.1 - 79.8 fb s | < 2.5

H

= 125.09 GeV, |y

H

m σ Observed +-1

• Stat. uncertainty
• Syst. uncertainty

SM prediction comb. bb τ τ VV γ γ comb. bb ZZ γ γ comb. τ τ WW ZZ γ γ comb. τ τ WW ZZ γ γ

ggF VBF VH ttH+tH

R.Turra (INFN Milano) Higgs to bosons (ATLAS) 11 February, 2019 23 / 27

SLIDE 26

H → ZZ → 4ℓ (differential) cross sections Categorize by flavour: 4µ, 2µ2e, 2e2µ, 4e Fit m4ℓ distribution Fiducial regions (by flavours), total and differential (p4ℓ

T , Nj) cross

sectionss

fid µ 4

σ

fid 4e

σ

fid 2e µ 2

σ

fid µ 2e2

σ

fid +4e µ 4

σ

fid µ 2e+2e2 µ 2

σ

fid (sum) l 4

σ

fid (comb) l 4

σ

H

σ 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8

Cross section [fb]

0.5 1 1.5 2 2.5 3 3.5 4 4.5

[fb]

10 20 30 40 50 60 70 80 90

[pb] ATLAS Preliminary

• 1

13 TeV, 79.8 fb l 4 → ZZ* → H

Data

• Syst. uncertainties

SM (ggF @N3LO + XH) MG5 FxFx + XH NNLOPS + XH HRes 2.3, NNLO+NNLL + XH

0.02 0.04 0.06 0.08 0.1 0.12

[fb/GeV]

l T,4

p /d σ d

ATLAS Preliminary

• 1

13 TeV, 79.8 fb l 4 → ZZ* → H

Data

• Syst. uncertainties

= 1.47, +XH K MG5 FxFx = 1.1, +XH K NNLOPS XH = VBF+WH+ZH+ttH+bbH

• syst. uncertainty

⊕ Total stat.

• value NNLOPS = 7.8%

p

• value MG5 FxFx = 9.4%

p

s

SM 95% CL × <3.75 σ Data

• Syst. uncertainties

= 1.47, +XH K MG5 FxFx = 1.1, +XH K NNLOPS XH = VBF+WH+ZH+ttH+bbH

• syst. uncertainty

⊕ Total stat.

10 15 20 30 45 60 80 120 200 350 1000

[GeV]

l T,4

p

0.5 1 1.5

Theory/Data

0.5 1 1.5 2 2.5 3 3.5

[fb] σ

ATLAS Preliminary

• 1

13 TeV, 79.8 fb l 4 → ZZ* → H Data

• Syst. uncertainties

= 1.47, +XH K MG5 FxFx = 1.1, +XH K NNLOPS XH = VBF+WH+ZH+ttH+bbH

• syst. uncertainty

⊕ Total stat.

• value NNLOPS = 18%

p

• value MG5 FxFx = 17%

p Data

• Syst. uncertainties

= 1.47, +XH K MG5 FxFx = 1.1, +XH K NNLOPS XH = VBF+WH+ZH+ttH+bbH

• syst. uncertainty

⊕ Total stat.

1 2 3 4 ≥ jets

N

0.5 1 1.5

Theory/Data

In addition study contact interaction with the Z boson, and left or right-handed leptons (in the pseudo-observable framework)

R.Turra (INFN Milano) Higgs to bosons (ATLAS) 11 February, 2019 24 / 27

SLIDE 27

Contanct interaction with pseudo observables H → 4ℓ

Using double differential m12 ⊕ m34 Extension to k-framework: probe anomalous coupling to leptons (left εL, right εR) and Z (k)

bins

34

m vs

12

m

bin 0 bin 1 bin 2 bin 3 bin 4

Events

10 20 30 40 50 60 70 80 90

• 1

13 TeV, 36.1 fb ATLAS 4l → ZZ* → H

Data =125 GeV)

H

Signal (m Background ZZ* +V, VVV t , t t Background Z+jets, t Uncertainty

[GeV]

12

m 50 60 70 80 90 100 110 [GeV]

34

m 10 20 30 40 50 60

bin 0 bin 1 bin 2 bin 3 bin 4 Data Signal Background

R.Turra (INFN Milano) Higgs to bosons (ATLAS) 11 February, 2019 25 / 27

SLIDE 28

γγ, ZZ ∗ → 4ℓ, WW ∗ → eνµν

eνμν

R.Turra (INFN Milano) Higgs to bosons (ATLAS) 11 February, 2019 26 / 27

SLIDE 29

H → γγ efficiencies

91 90 38 3 24 1 3 8 2 5 5 5 51 1 25 5 12 1 2 1 76 2 24 6 1 10 8 8 2 4 1 70 1 10 1 2 4 3 3 69 3 4 3 34 2 4 2 1 1 8 56 1 3 9 4 26 9 3 6 3 1 10 71 2 1 11 4 25 30 10 3 8 4 1 11 79 2 3 8 5 14 43 11 7 4 2 26 14 4 5 1 1 4 3 18 30 3 1 1 36 68 3 8 2 4 5 18 3 2 2 2 20 35 3 1 4 8 10 2 7 10 11 9 10 4 6 4 5 3 5 3 1 12 23 3 2 1 1 22 25 69 77 5 2 44 49 6 4 81 2 15 18 1 1 18 1 1 1 2 1 1 4 5 9 16 1 54 75 86 91 76 90 95 2 2 1 6 4 2 1 13 5 1 1 1 2 2 3 2 2 2 1 1 1 1 1 ggF 0J Cen ggF 0J Fwd ggF 1J Low ggF 1J Med ggF 1J High ggF 1J BSM ggF 2J Low ggF 2J Med ggF 2J High ggF 2J BSM BDT loose

Hjj T

VBF Low-p BDT tight

Hjj T

VBF Low-p BDT loose

Hjj T

VBF High-p BDT tight

Hjj T

VBF High-p VH had BDT loose VH had BDT tight qqH BSM VH MET Low VH MET High VH lep Low VH lep High VH dilep ttH had BDT4 ttH had BDT3 ttH had BDT2 ttH had BDT1 ttH lep BDT3 ttH lep BDT2 ttH lep BDT1

Reconstruction Category

ggF (0-jet) < 60 GeV)

H T

ggF (1-jet, p < 120 GeV)

H T

p ≤ ggF (1-jet, 60 < 200 GeV)

H T

p ≤ ggF (1-jet, 120 200 GeV) ≥

H T

ggF (1-jet, p < 60 GeV)

H T

2-jet, p ≥ ggF ( < 120 GeV)

H T

p ≤ 2-jet, 60 ≥ ggF ( < 200 GeV)

H T

p ≤ 2-jet, 120 ≥ ggF ( 200 GeV) ≥

H T

2-jet, p ≥ ggF ( ggF (VBF-like, 3-jet veto) ggF (VBF-like, 3-jet) Hqq (VBF-like 3-jet veto) → qq Hqq (VBF-like 3-jet) → qq Hqq (VH) → qq Hqq (rest) → qq 200 GeV) ≥

j T

Hqq (p → qq ν Hl → qq Hll → qq Hll → gg ttH tHq tWH bbH

STXS Region 10 20 30 40 50 60 70 80 90 100

Simulation Preliminary ATLAS 125.09 GeV =

H

= 13 TeV, m s , γ γ → H

Region purity / Category (%)

R.Turra (INFN Milano) Higgs to bosons (ATLAS) 11 February, 2019 27 / 27