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
Aparajita Da*agupta Pheno2015
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
Aparajita Da*agupta Pheno2015
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
"+
""
"+
""
Aparajita Da*agupta Pheno2015
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
Aparajita Da*agupta Pheno2015
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.
Aparajita Da*agupta Pheno2015
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
Aparajita Da*agupta Pheno2015
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
Aparajita Da*agupta Pheno2015
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
Aparajita Da*agupta Pheno2015
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
Aparajita Da*agupta Pheno2015
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
Aparajita Da*agupta Pheno2015
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
Aparajita Da*agupta Pheno2015
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
Aparajita Da*agupta Pheno2015
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
Aparajita Da*agupta Pheno2015
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!
Aparajita Da*agupta Pheno2015
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