recent electroweak results at atlas -...

Recent Electroweak results at ATLAS

Aparajita Da*agupta

Pheno2015, 4th-‐6th May Pi*sburgh, U.S.A

Aparajita Da*agupta Pheno2015

Introduction

Following processes have been measured recently and will be discussed in this talk v  Forward backward asymmetry in lepton pair production, Weinberg angle extraction

(7 TeV): v  Inclusive (7 & 8TeV):

v  (8TeV): v  Fully leptonic decays of WW (8TeV) v  Semi-leptonic decays of (7TeV): v  Simultaneous measurement of (8TeV): v  production with sensitivity to Vector Boson Fusion (8TeV): v  Same sign with sensitivity to Vector Boson Scattering (8TeV):

2

Wγγ

Z→ 4leptons

WW, Z→ ττ , t t_

Z + 2 jets

WW + 2 jets

WW +WZ


Forward backward asymmetry ( ) in lepton pair production •  Measures as a function of the dilepton mass.

lept

eff!2sin

0.225 0.23 0.235

PDG Fit

LEP+SLC

LRSLD, A

0,l

FBLEP, A

0,b

FBLEP, A

CDF

D0

CMS

ATLAS combined

µATLAS,

ATLAS, e CF

ATLAS, e CC ATLAS

-1 = 7 TeV, 4.8 fb s

arXiv:1503.03709

3

AFB

Agrees with the current world average CS*ecos

1< 0.5< 0 0.5 1

Events

/ 0

.1

10

20

30

40

50

60

70

310=

-1 = 7 TeV, 4.8 fb s

Data 2011

eeA*aZ/

Other backgrounds

Multijets

ATLAS

CF electron

> 25 GeVT

p

| < 2.47C

d|

| < 4.9F

d2.5 < |

Angle between lepton and quark in rest frame of the dilepton system

AFB

•  Effective weak mixing angle is extracted using detector level asymmetry values.

sin2θefflept

aJer correcKng for detector effects AFB

sin2θefflept = 0.2308± 0.0005(stat)± 0.0006(syst)± 0.0009(PDF)

θcs =

cor

FB

A

0.6!

0.4!

0.2!

0

0.2

0.4

0.6

0.8

1

1.2

Data, full unfolding

ee"*#PYTHIA, Z/

ATLAS-1 = 7TeV, 4.8fb s

CC electron

[GeV]eem70 210 210$2 310

%/&

2!1!012


Z/!!

Z!/!!

q̄

q

"+

"+

""

""

Branching fraction for the Z boson decay to 4l measured =

•  Test of the SM and a cross-check of the detector response to the 4l final state from Higgs decays.

[GeV]4lm

75 80 85 90 95 100 105

Events

/ 3

GeV

0

20

40

60

80

100

120 ATLAS

-1 = 7 TeV, 4.5 fbs-1

(c)

= 8 TeV, 20.3 fbs

Data

ZBkg

stat+syst!

4l"Z

•  determination of with improved statistical precision.

•  Background is

< 1% of the total expected signal.

Zà4l production cross section at the Z resonance

•  event selection closely follows analysis.

•  XS measured in the phase space > 5 GeV and 80 < < 100 GeV. •  XS for 4e and 4µ are larger than

for 2e2µ due to the interference between the two same-flavor lepton pairs.

4

ΓZ → 4l / ΓZ

(3.20± 0.25± 0.13)×10−6

M4l

(ΓZ → 4l / ΓZ )powheg = (3.33± 0.13)×10−6

ml+l−

Z→ 4lH→ ZZ→ 4l

Phys. Rev. Le+. 112, 231806 (2014)

Z!/!!

Z!/!!

q̄

q

"+

""

"+

""


Multiboson production processes

production and limits on anomalous Quartic Gauge Couplings (aQGC). Fully leptonic decays of WW. Semi-leptonic decays of (WV) and limits on anomalous Triple Gauge Couplings (aTGC). simultaneous measurement.

5

Wγγ

WW, Z→ ττ , t t_

WW +WZ


Evidence of production & Limits on aQGC

[GeV]γγm0 100 200 300 400 500

Even

ts /

50 G

eV

0

10

20

30

40

50

60

70 DataγγW

γZj + WjjγW

+ jetsγγOther backgrounds

ATLAS

-1 = 8 TeV, 20.3 fbs 0)≥

jetsmuon channel (N

arXiv:1503.03243

6

]-2 [TeV2Λ

W0a

]-2 [TeV2Λ

WCa

]-4 [TeV4Λ

ET0f

LEP WW→ γγD0 γCMS WV

WW→ γγCMS γγATLAS W

ATLAS

AQGC Limits 95% CL

10 210 310 410 510-102-103-104-105-10

•  Largest systematic from data-driven BG.

•  XS obtained using a maximum-likelihood fit.

•  aQGC limits set for (exclusive) and > 300GeV. Limits better or similar to LEP and D0. •  The W final state is expected to be particularly

sensitive to the T0 operator.

Wγγ

•  First evidence of triple gauge boson production with

> 3 significance for inclusive selection ( ). •  Largest background: jets

faking photon or lepton, data based estimate.

σ

Λ

N jets >= 0

mγγ N jets = 0

represents the scale at which new physics appears, and f the coupling of the respecKve operator.


Fully leptonic WW (à lvlv) cross-section

7

ATLAS-‐CONF-‐2014-‐033

•  Studied in three channels, •  Major backgrounds include

Drell-Yan events, top (ttbar & singletop) production,

W+jets, and diboson events ( ).

[pb]WWtotσ

10 20 30 40 50 60 70 80 90 100

SM Prediction WW: MCFM NLO CT10→qq/qg

WW: MCFM LO CT10→gg WW: NNLO MSTW2008→ H →gg

WW

Measuredcross sections

-e+e

-µ+µ

±µ±e

Combined

ATLAS Preliminary-1 Ldt = 20.3 fb∫

= 8 TeVs

•  XS high with respect to theory, ~2 . •  prediction sensitive to choice of pdf; uses

CT10 pdf. •  Lots of theoretical interest in discrepancy,

particularly w.r.t. jet-veto efficiency.

σ

Jet multiplicity0 1 2 3 4 5 6 7

Even

ts

500

1000

1500

2000

2500

3000 ATLAS Preliminary-1 Ldt = 20.3 fb∫ = 8 TeV, s

channelsν-µ ν+µ + ν- eν+e

Data WW MC Top MC Zjets MC Wjets MC other diboson MCstat. unc.

Cut on Jet mulKplicity (jet veto) to reduce *bar background

σ

e+e−,e±µ ,µ+µ−

WW,ZZ,W (γ *)

Z/�⇤

q

q̄

W

W

TGC vertex


Semileptonic WV (à lvjj) cross-section & Limits on aTGC

50 100 150 200 250

Even

ts /

5 G

eV

0

2000

4000

6000

8000

10000

DataWW/WZtop quarksmultijetW/Z + jets

-1L dt = 4.6 fb∫ = 7 TeVs

+ 2 jetsν e→W

ATLAS

Dijet mass [GeV]50 100 150 200 250

Dat

a/SM

0.80.91.01.11.2

•  Compared to fully leptonic, the semi-leptonic channel has a larger branching fraction but larger backgrounds.

JHEP01(2015)049

8

95% CL Limits-0.4 -0.2 0 0.2 0.4 0.6 0.8

γκΔ

λ

1ZgΔ

LEP comb.∞ = FFΛ, -10.7 fb

= 7TeVsjj, νATLAS l∞ = FFΛ, -14.6 fb

= 7TeVsjj, νCMS l∞ = FFΛ, -15.0 fb

= 1.96TeVsD0 comb., = 2TeVFFΛ, -18.6 fb

= 7TeVsATLAS WW, ∞ = FFΛ, -14.6 fb

= 7TeVsCMS WW, ∞ = FFΛ, -14.9 fb

= 7TeVsATLAS WZ, ∞ = FFΛ, -14.6 fb

= 7TeVs, γATLAS W∞ = FFΛ, -14.6 fb

= 7TeVs, γCMS W∞ = FFΛ, -15.0 fb

ATLAS95% CL intervals

LEP Scenario

•  WV signal is extracted by a fit to the dijet mass distribution.

•  3.4 evidence.

•  W+jets shape is a dominant systematic.

Dijet is used to place aTGC limits; improved TGC limits similar or be*er than LEP

•  Signal selection requires one lepton, large missing Et and two jets.

σ pT


WW, Ztautau and ttbar simultaneous cross-section measurements Phys. Rev. D 91, 052005

Even

ts /

10 G

eV

0

200

400

600

800

1000

1200

1400

1600

1800

2000

= 7 TeV (2011)sData syst. uncertainty⊕Stat.

ttττ→Z

WWPrompt bkgd.Fake or non-prompt bkgd.

ATLAS-1 L dt = 4.6 fb∫ µeOS

[GeV]missTE

0 20 40 60 80 100 120 140 160 180 200

Dat

a/Fi

tted

0.81

1.21.4

•  First simultaneous measurement of

XSs at this energy.

: Large met, large

WW: Large missing Et (met), small

9

small met, smaller than WW

t t,_

WW, Z /γ * → ττ

•  Broader test of the SM than dedicated XS measurements by unifying the fiducial region,

object and event requirements, and background estimations.

t t _

Z→ ττ

•  Processes considered in a 2D parameter space spanned by met and , allowing the simultaneous extraction of their XSs.

N jetsN jets

N jets

N jets


Production processes sensitive to Vector Boson Fusion & Scattering

Electroweak production of dijets in association with a Z boson – sensitivity to Vector Boson Fusion (VBF) production of Z Electroweak production of WWjj - sensitivity to Vector Boson Scattering (VBS)

10


Electroweak production of dijets in association with a Z-boson

W�

W+Z

q

q

q0

µ+, e+

µ�, e�

q0

[GeV]jjm500 1000 1500 2000 2500 3000 3500

MC

Dat

a

0.5

0.6

0.7

0.8

0.9

1

default 0.8≤ y

> 0.8y = 1jetN

2≥ jetN > 38 GeV

Tp

38 GeV≤ T

25 < p < 0.9,π(j,j)/φΔ

> 20 GeVjjT

p

ATLAScontrol region

= 8 TeVs

•  Choice of control region has negligible impact on extracted signal XS.

Signal purity increases at high dijet mass, XS extraction from fit to dijet mass spectrum. Good agreement with theory.

•  Interacting quarks result in high pT jets •  High dijet mass •  Large angular separation between jets

JHEP04(2014)031

11

yΔ0 1 2 3 4 5 6 7

Nor

mal

ised

to u

nity

-210

-110

1ATLAS EW Zjj

Background

[GeV]jjm0 500 1000 1500 2000 2500 3000

Nor

mal

ised

to u

nity

-410

-310

-210

-110

1ATLAS EW Zjj

Background

•  Background modeling by simulation corrected using data in signal suppressed control regions.

Observation of Electroweak Zjj production, significance > 5 . Studied as a probe of colour-singlet exchange and as a validation of the VBF process.

σ

Z

g

q

µ+, e+

µ�, e�

q

g

EWK strong


Electroweak production of dijets in association with a Z-boson

High : sensiKve to difference between strong

and electroweak Zjj

Data corrected for detector effects compared to particle level predictions from Sherpa and Powheg: Bayesian iterative unfolding

•  Less quark/gluon radiation from EW Zjj: better balance between tagging jets against Z Boson visible at high

•  :transverse-momentum balance between the Z boson ( the two leptons ) and the two leading jets.

0 1 2 3 4 5 6 7

< 0

.15

cut e

ffici

ency

bala

nce

Tp

0.5

0.6

0.7

0.8

0.9

1 ATLAS-1 L dt = 20.3 fb∫

= 8 TeVsbaseline region

Data (2012)

Sherpa Zjj (QCD + EW)

Sherpa Zjj (QCD)

Powheg Zjj (QCD + EW)

Powheg Zjj (QCD)

0 1 2 3 4 5 6 7

D

ata

Sher

pa

0.8

1

1.2

yΔ0 1 2 3 4 5 6 7

D

ata

Pow

heg

0.8

1

1.2

0 1 2 3 4 5 6 7

yΔ

dσd

σ1

-310

-210

-110

1ATLAS

-1 L dt = 20.3 fb∫ = 8 TeVs

search region

Data (2012)

Sherpa Zjj (QCD + EW)

Sherpa Zjj (QCD)

Powheg Zjj (QCD + EW)

Powheg Zjj (QCD)

0 1 2 3 4 5 6 7

D

ata

Sher

pa

1

1.5

yΔ0 1 2 3 4 5 6 7

D

ata

Pow

heg

0.81

1.2

12

Δy

Δy

pT balance


Evidence of electroweak production of WWjj

q

q

q0

W+

W+

q0

q

q

q0

W+

W+

q0

strong producKon cross secKon does not dominate the electroweak cross secKon

•  Key process to probe the nature of EW symmetry breaking.

•  1st evidence for a process involving a VVVV vertex, with 3.6 significance for the electroweak process.

•  Events required to have two leptons with same charge and at least two jets

Phys. Rev. Le+. 113, 141803

13

σ

|jj

yΔ|0 1 2 3 4 5 6 7 8 9

Even

ts5

10

15

20

25

30 Data 2012 Syst. Uncertainty

jj Electroweak±W± Wjj Strong±W± W

Prompt Conversions Other non-prompt

ATLAS = 8 TeVs, -120.3 fb

> 500 GeVjjm

VBS region: cut on angular separaKon between jets


14

Control Region Trilepton ! 1 jet b-tagged Low mjj

e±e± exp. 36 ± 6 278 ± 28 40 ± 6 76 ± 9data 40 288 46 78

e±µ± exp. 110 ± 18 288 ± 42 75 ± 13 127 ± 16data 104 328 82 120

µ±µ± exp. 60 ± 10 88 ± 14 25 ± 7 40 ± 6data 48 101 36 30

Conversion & prompt

Non-‐prompt combined Type of

background prompt •  Largest background from

, conversions ( ) and non-EWK . •  Background predictions are tested

in several signal suppressed same-charge control regions.

4α

-0.4 -0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.4

5α

-0.6

-0.4

-0.2

0

0.2

0.4

0.6ATLAS�20.3 fb-1, s = 8 TeV�pp → W± W± jj�K-matrix unitarization

68% CL95% CLexpected 95% CLStandard Model

confidence intervals

aQGC Limits at 95% CL. •  K-matrix unitarization method

is used •  Deviations from SM are

parameterized using a4 and a5 parameters

Evidence of electroweak production of WWjj

WZ→ lvllγ Wγ + jets

WWjj


15

summary

•  These measurements provide a good test of the Electroweak sector of SM and probes sensitivity to and possibilities of new physics.

•  Many of these measurements are background validations for other signal processes.

•  With 8 TeV ATLAS data, for the 1st time we have evidence of Vector Boson

Scattering. •  First measurement of the Electroweak production of dijets and a Z, with

sensitivity to Vector Boson Fusion. •  First evidence of Triboson production.

•  Strong limits on aTGC and aQGC has been possible with 7 and 8 TeV data.

•  Measurements have good agreement with theory. •  More measurements in progress!


Backup

16

Model ECM [TeV]!L dt[fb!1] Measurement Theory Reference

!fid(W+Z " qq) 7 4.6 ! = 8.5 ± 0.8 ± 1.5 pb ! = 5.1 ± 0.5 pb (MCFM) New J. Phys. 16, 113013 (2014)!fid(ZZ# " 4") 7 4.6 ! = 29.8 + 3.8 ! 3.5 + 2.1 ! 1.9 fb ! = 25.6 + 1.3 ! 1.1 fb (PowhegBox & gg2ZZ) JHEP 03, 128 (2013)!fid(ZZ " 4") 7 4.6 ! = 25.4 + 3.3 ! 3.0 + 1.6 ! 1.4 fb ! = 20.9 + 1.1 ! 0.9 fb (PowhegBox & gg2ZZ) JHEP 03, 128 (2013)!fid(ZZ " 4") 8 20.3 ! = 20.7 + 1.3 ! 1.2 ± 1.0 fb ! = 21.1 + 0.9 ! 0.7 fb (MCFM) ATLAS-CONF-2013-020!total(pp"ZZ"4") 7 4.5 ! = 76.0 ± 18.0 ± 4.0 fb ! = 90.0 ± 1.6 fb (Powheg) arXiv:1403.5657 [hep-ex]!total(pp"ZZ"4") 8 20.3 ! = 107.0 ± 9.0 ± 5.0 fb ! = 104.9 ± 1.7 fb (Powheg) arXiv:1403.5657 [hep-ex]!fid(WZ " "#"") 8 13.0 ! = 99.2 + 3.8 ! 3.0 + 6.0 ! 6.2 fb ! = 99.2 ± 3.6 fb (MCFM) ATLAS-CONF-2013-021!fid(WW"eµ) [njet$0] 7 4.6 ! = 563.0 ± 28.0 + 79.0 ! 85.0 fb ! = 536.0 ± 29.0 fb (MCFM) arXiv:1407.0573 [hep-ex]!fid(WW"eµ) [njet=0] 7 4.6 ! = 262.3 ± 12.3 ± 23.1 fb ! = 231.4 ± 15.7 fb (MCFM) PRD 87, 112001 (2013)!fid(WW"µµ) [njet=0] 7 4.6 ! = 73.9 ± 5.9 ± 7.5 fb ! = 58.9 ± 4.0 fb (MCFM) PRD 87, 112001 (2013)!fid(WW"ee) [njet=0] 7 4.6 ! = 56.4 ± 6.8 ± 10.0 fb ! = 54.6 ± 3.7 fb (MCFM) PRD 87, 112001 (2013)!fid(W±W±jj) EWK 8 20.3 ! = 1.3 ± 0.4 ± 0.2 fb ! = 0.95 ± 0.06 fb (PowhegBox) PRL 113, 141803 (2014)!fid(W$$ " "#$$) 8 20.3 ! = 6.1 + 1.1 ! 1.0 ± 1.2 fb ! = 2.9 ± 0.16 fb (MCFM NLO) arXiv:1503.03243 [hep-ex]!fid(W$$ " "#$$)[njet=0] 8 20.3 ! = 2.9 + 0.8 ! 0.7 + 1.0 ! 0.9 fb ! = 1.88 ± 0.2 fb (MCFM NLO) arXiv:1503.03243 [hep-ex]!fid(Z$ " ""$)[njet = 0] 7 4.6 ! = 1.05 ± 0.02 ± 0.11 pb ! = 1.107 + 0.012 ! 0.018 pb (NNLO) PRD 87, 112003 (2013)!fid(Z$ " ""$) 7 4.6 ! = 1.31 ± 0.02 ± 0.12 pb ! = 1.327 + 0.026 ! 0.037 pb (NNLO) PRD 87, 112003 (2013) arXiv:1407.1618 [hep-ph]!fid(W$ " "#$)[njet = 0] 7 4.6 ! = 1.76 ± 0.03 ± 0.22 pb ! = 1.674 + 0.056 ! 0.064 pb (NNLO) PRD 87, 112003 (2013)!fid(W$ " "#$) 7 4.6 ! = 2.77 ± 0.03 ± 0.36 pb ! = 2.658 ± 0.11 pb (NNLO) PRD 87, 112003 (2013) arXiv:1407.1618 [hep-ph]!fid($$)[!R$$ > 0.4] 7 4.9 ! = 44.0 + 3.2 ! 4.2 pb ! = 44.0 ± 6.0 pb (2"NNLO) JHEP 01, 086 (2013)WZ 7 4.6 ! = 19.0 + 1.4 ! 1.3 ± 1.0 pb ! = 17.6 + 1.1 ! 1.0 pb (MCFM) EPJC 72, 2173 (2012)WZ 8 13.0 ! = 20.3 + 0.8 ! 0.7 + 1.4 ! 1.3 pb ! = 20.3 ± 0.8 pb (MCFM) ATLAS-CONF-2013-021ZZ 7 4.6 ! = 6.7 ± 0.7 + 0.5 ! 0.4 pb ! = 5.89 + 0.22 ! 0.18 pb (MCFM) JHEP 03, 128 (2013)ZZ 8 20.3 ! = 7.1 + 0.5 ! 0.4 ± 0.4 pb ! = 7.2 + 0.3 ! 0.2 pb (MCFM) ATLAS-CONF-2013-020Zjj EWK 8 20.3 ! = 54.7 ± 4.6 + 9.9 ! 10.5 fb ! = 46.1 ± 1.2 fb (PowhegBox) JHEP 04, 031 (2014)WW+WZ""#qq 7 4.6 ! = 1.37 ± 0.14 ± 0.37 pb ! = 1.24 ± 0.09 pb (MC@NLO) JHEP 01, 049 (2015)WW+WZ 7 4.6 ! = 68.0 ± 7.0 ± 19.0 pb ! = 61.1 ± 2.2 pb (MC@NLO) JHEP 01, 049 (2015)WW 7 4.6 ! = 51.9 ± 2.0 ± 4.4 pb ! = 44.7 + 2.1 ! 1.9 pb (MCFM) PRD 87, 112001 (2013)WW 8 20.3 ! = 71.4 ± 1.2 + 5.5 ! 4.9 pb ! = 58.7 + 3.0 ! 2.7 pb (MCFM) ATLAS-CONF-2014-033

$$ 7 4.9 ! = 44.0 + 3.2 ! 4.2 pb ! = 44.0 ± 6.0 pb (2"NNLO) JHEP 01, 086 (2013)!fid(H " $$, ZZ(4")) 8 20.3 ! = 33.04 ± 5.35 ± 1.59 pb ! = 22.16 + 1.99 ! 2.0 pb (LHC-XS ggF + XH) Preliminary!fid(H " ZZ " 4") 8 20.3 ! = 2.11 + 0.53 ! 0.47 ± 0.08 fb ! = 1.3 ± 0.13 fb (LHC-XS) arXiv:1408.3226 [hep-ex]!fid(gg " H " WW) 8 20.3 ! = 4.6 ± 0.9 + 0.8 ! 0.7 pb ! = 4.2 ± 0.5 pb (LHC-XS) arXiv:1412.2641 [hep-ex]!fid(VBF H " WW) 8 20.3 ! = 0.51 + 0.17 ! 0.15 + 0.13 ! 0.08 pb ! = 0.35 ± 0.02 pb (LHC-XS) arXiv:1412.2641 [hep-ex]!fid(H"$$) 8 20.3 ! = 43.2 ± 9.4 + 3.4 ! 3.1 fb ! = 30.5 ± 3.2 fb (LHC-XS) Preliminaryt̄tH 8 20.3 ! = 0.24 ± 0.11 pb ! = 0.128 ± 0.014 pb (LHC-HXSWG) ATLAS-CONF-2015-007

H ggF 8 20.3 ! = 23.9 + 3.9 ! 3.5 pb ! = 19.2 ± 2.0 pb (LHC-HXSWG) ATLAS-CONF-2015-007H VBF 8 20.3 ! = 2.43 + 0.6 ! 0.55 pb ! = 1.57 ± 0.04 pb (LHC-HXSWG) ATLAS-CONF-2015-007H 7 4.5 ! = 21.8 + 3.3 ! 3.1 pb ! = 17.4 ± 1.6 pb (LHC-HXSWG) ATLAS-CONF-2015-007H 8 20.3 ! = 27.6 + 3.8 ! 3.5 pb ! = 22.3 ± 2.0 pb (LHC-HXSWG) ATLAS-CONF-2015-007t̄t$ 7 4.6 ! = 63.0 ± 8.0 + 17.0 ! 13.0 fb ! = 48.0 ± 10.0 fb (Whizard+NLO) arXiv:1502.00586 [hep-ex]t̄tZ 7 4.7 ! < 0.71 pb ! = 0.14 ± 0.028 pb (HELAC-NLO) ATLAS-CONF-2012-126t̄tZ 8 20.3 ! = 150.0 + 55.0 ! 50.0 ± 21.0 fb ! = 206.0 ± 45.0 fb (HELAC-NLO) ATLAS-CONF-2014-038t̄tW 8 20.3 ! = 300.0 + 120.0 ! 100.0 + 70.0 ! 40.0 fb ! = 232.0 ± 51.0 fb (MCFM) ATLAS-CONF-2014-038

t̄t [njet $ 8] 7 4.7 ! = 0.0425 ± 0.004 ± 0.012 pb JHEP 01, 020 (2015)t̄t [njet = 7] 7 4.7 ! = 0.161 ± 0.007 ± 0.033 pb JHEP 01, 020 (2015)t̄t [njet = 6] 7 4.7 ! = 0.611 ± 0.024 ± 0.083 pb JHEP 01, 020 (2015)t̄t [njet = 5] 7 4.7 ! = 1.72 ± 0.04 ± 0.16 pb JHEP 01, 020 (2015)t̄t [njet = 4] 7 4.7 ! = 3.76 ± 0.05 ± 0.27 pb JHEP 01, 020 (2015)t̄t 7 4.6 ! = 182.9 ± 3.1 ± 6.4 pb ! = 177.0 + 10.0 ! 11.0 pb (top++ NNLO+NNLL) Eur. Phys. J. C 74: 3109 (2014)t̄t 8 20.3 ! = 242.4 ± 1.7 ± 10.2 pb ! = 252.9 + 13.3 ! 14.5 pb (top++ NNLO+NNLL) Eur. Phys. J. C 74: 3109 (2014)Wt 7 2.0 ! = 16.8 ± 2.9 ± 3.9 pb ! = 15.7 ± 1.1 pb (NLO+NLL) PLB 716, 142-159 (2012)Wt 8 20.3 ! = 27.2 ± 2.8 ± 5.4 pb ! = 22.4 ± 1.5 pb (NLO+NLL) ATLAS-CONF-2013-100

tt!chan 7 4.6 ! = 68.0 ± 2.0 ± 8.0 pb ! = 64.6 + 2.7 ! 2.0 pb (NLO+NLL) PRD 90, 112006 (2014)tt!chan 8 20.3 ! = 82.6 ± 1.2 ± 12.0 pb ! = 87.8 + 3.4 ! 1.9 pb (NLO+NLL) ATLAS-CONF-2014-007

ts!chan 7 0.7 ! < 26.5 pb ! = 4.6 ± 0.3 pb (NLO+NNLL) ATLAS-CONF-2011-118

ts!chan 8 20.3 ! < 14.6 pb ! = 5.61 ± 0.22 pb (NLO+NNL) arXiv:1410.0647 [hep-ex]

Standard Model Production Cross Section Measurements I

Status: March 2015

ATLAS Preliminary

Run 1"s = 7, 8 TeV

Aparajita Da*agupta Pheno2015 17

recent electroweak results at atlas -...

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