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Probing QCD and hadron physics: highlights of experimental results. Chiara Roda Universita` and INFN of Pisa ICHEP2014 - Valencia. Why bother ?. Understanding/testing the QCD theory of SM in a new kinematic range never explored before (LHC) at many different scales (HERA, TeVatron, LHC)

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probing qcd and hadron physics highlights of experimental results

Probing QCD and hadron physics: highlights of experimental results

Chiara RodaUniversita` and INFN of Pisa

ICHEP2014 - Valencia

C.Roda – Universita` & INFN Pisa

why bother
Why bother ?
  • Understanding/testing the QCD theory of SM
  • in a new kinematic range never explored before (LHC)
  • at many different scales (HERA, TeVatron, LHC)
  • in a variety of initial states: ep, ppbar, pp

C.Roda – Universita` & INFN Pisa

why bother1
Why bother ?
  • Understanding/testing the QCD theory of SMin a new kinematic range never explored before (LHC)
  • at many different scales (HERA, TeVatron, LHC)
  • in a variety of initial states: ep, pp, pp

LHC collider

pp - √s=7-8 TeV

Operating from 2010

Tevatron collider

pp - √s=1.8 - 1.96 TeV

Operated 1987-2011

HERA collider

e±p - √s=225-320 GeV

Operated 1992-2007

C.Roda – Universita` & INFN Pisa

why bother2
Why bother ?
  • Understanding/testing the QCD theory of SMin a new kinematic range never explored before (LHC)
  • at many different scales (HERA, TeVatron, LHC)
  • in a variety of initial states: ep, ppbar, pp

Our level of understanding and modeling of the QCD interactions has direct impact on the potential we have for precision measurements and discovery

Largest syst. For Higgs cross-section is from σ(ggF): 7% scales / 7% PDFs

W/Z+jet is often one of the largest background to top-quark, SUSY, Higgs and exotic searches.

C.Roda – Universita` & INFN Pisa

the ingredients in the predictions
The ingredients in the predictions…

C.Roda – Universita` & INFN Pisa

the ingredients in the predictions1
The ingredients in the predictions…

Hard Scattering and parton shower: fixed order NLO partonic calculations (NLOJET++,MCFM,BlackHat), LO+PS (Pythia, Herwig), High multi. LO+PS (Alpgen, Sherpa, Madgraph,…). State of the art: NLO+PS ([email protected]+PS, POWHEG+PS, [email protected])

C.Roda – Universita` & INFN Pisa

the ingredients in the predictions2
The ingredients in the predictions…

Hard Scattering and parton shower: fixed order NLO partonic calculations (NLOJET++,MCFM,BlackHat), LO+PS (Pythia, Herwig), High multi. LO+PS (Alpgen, Sherpa, Madgraph,…). State of the art: NLO+PS ([email protected]+PS, POWHEG+PS, [email protected])

PDF: CTEQ/CT, NNPDF, MSTW, ABM, HERAPDF…

Differences: data used the fit, αsvalue, treatment of errors, parameterization…

C.Roda – Universita` & INFN Pisa

the ingredients in the predictions3
The ingredients in the predictions…

Hard Scattering and parton shower: fixed order NLO partonic calculations (NLOJET++,MCFM,BlackHat), LO+PS (Pythia, Herwig), High multi. LO+PS (Alpgen, Sherpa, Madgraph,…). State of the art: NLO+PS ([email protected]+PS, POWHEG+PS, [email protected])

Mostly anti-kT – various cone sizes

PDF: CTEQ/CT, NNPDF, MSTW, ABM, HERAPDF…

Differences: data used the fit, αsvalue, treatment of errors, parameterization…

Measurements are unfolded at particle level to be compared with predictions

C.Roda – Universita` & INFN Pisa

the ingredients in the predictions4
The ingredients in the predictions…

Hard Scattering and parton shower: fixed order NLO partonic calculations (NLOJET++,MCFM,BlackHat), LO+PS (Pythia, Herwig), High multi. LO+PS (Alpgen, Sherpa, Madgraph,…). State of the art: NLO+PS ([email protected]+PS, POWHEG+PS, [email protected])

A sizeable contribution in understanding our measurements also comes from the quality of modeling of soft hadronic physics… no results in this talk but the measurements are used for the tuning of MC used.

Mostly AntikT – various cone sizes

PDF: CTEQ/CT, NNPDF, MSTW, AMB, HERAPDF…

Differences: data used the fit, αsvalue, treatment of errors, parameterization…

Measurements are unfolded at particle level to be compared with predictions

C.Roda – Universita` & INFN Pisa

jet cross sections
Jet cross-sections

Just two examples among the many results …

C.Roda – Universita` & INFN Pisa

inclusive cross section @ 8 tev

STDM-2013-11 CMS-PAS-FSQ-12-031 CMS-PAS-SMP-12-012

Inclusive cross-section @ 8 TeV

8 TeV

16 orders of magnitude

Low pile-up data to extend to the low pT range down to 20 GeV and |y|<4.7

20 Gev – 2 TeV

LHC data allows pQCD tests in a new kinematic regime – extended in pT and y

Covers 16 orders of magnitude / two jet sizes

Reference prediction: NLOJET + NNPDF2.1 but other PDF tested

C.Roda – Universita` & INFN Pisa

more challenge higher multiplicities
More challenge… higher multiplicities

3-jet

|Y*|=|y1-y2| + |y2-y3| + |y1-y3|

9 orders of magnitude

Mjjj = [0.38,1.2] TeV

Distributions are sensitive both to jet pT and to the angular distributions

Data are compared to many different PDFs, different jet sizes

Data can be used to constrain PDFs (exp and theory uncertainties similar)

C.Roda – Universita` & INFN Pisa

jet with different sizes what we learn

arXiv:1406;0324

Jet with different sizes … what we learn

Inclusive cross-section ratio

R(0.5,0.7) = [dσ(0.5)/dpT]/[dσ(0.7)/dpT]

Variable sensitive to pertubative

radiation, hadronization,

underlying-event

C.Roda – Universita` & INFN Pisa

jet with different sizes what we learn1

arXiv:1406;0324

Jet with different sizes … what we learn

R(0.5,0.7) = [dσ(0.5)/dpT]/[dσ(0.7)/dpT]

C.Roda – Universita` & INFN Pisa

jet with different sizes what we learn2

arXiv:1406;0324

Jet with different sizes … what we learn

R(0.5,0.7) = [dσ(0.5)/dpT]/[dσ(0.7)/dpT]

LONLO

C.Roda – Universita` & INFN Pisa

jet with different sizes what we learn3

arXiv:1406;0324

Jet with different sizes … what we learn

R(0.5,0.7) = [dσ(0.5)/dpT]/[dσ(0.7)/dpT]

LONLO

NLONLO*NP

C.Roda – Universita` & INFN Pisa

jet with different sizes what we learn4

arXiv:1406;0324

Jet with different sizes … what we learn

R(0.5,0.7) = [dσ(0.5)/dpT]/[dσ(0.7)/dpT]

Best description need NLO and parton shower are needed to describe correctly the ratio …

C.Roda – Universita` & INFN Pisa

what we learned from jets
what we learned from jets …

Inclusive and multiple jet cross-sections have been measured in ATLAS and CMS extending the previously tested kinematic range

Good agreement is found with NLOJET++ prediction

Various PDF tested and most of them show good data description with exception of HERAPDF and in particular ABM11 which show disagreement in some kinematic regions

POWHEG+PYTHIA is found to give the best description of inclusive jet cross-section for different jet sizes

Measurements are used as input to constrain gluon PDFs

C.Roda – Universita` & INFN Pisa

strong measurement
α strong measurement

C.Roda – Universita` & INFN Pisa

s measurement

CMS-PAS-SMP-12-028 CMS-PAS-SMP-12-027 arXiv 1406:470

αs measurement

World average (2014)

αs(MZ)= 0.1185 ± 0.0006 (0.5%)

https://twiki.cern.ch/twiki/bin/view/CMSPublic/PhysicsResultsSMP

C.Roda – Universita` & INFN Pisa

s measurement1

CMS-PAS-SMP-12-028 CMS-PAS-SMP-12-027 arXiv 1406:470

αs measurement

World average (2014)

αs(MZ)= 0.1185 ± 0.0006 (0.5%)

CMS Most recent: inclusive jet (5%)

https://twiki.cern.ch/twiki/bin/view/CMSPublic/PhysicsResultsSMP

C.Roda – Universita` & INFN Pisa

s measurement2

CMS-PAS-SMP-12-028 CMS-PAS-SMP-12-027 arXiv 1406:470

αs measurement

World average (2014)

αs(MZ)= 0.1185 ± 0.0006 (0.5%)

CMS Most recent: inclusive jet (5%)

https://twiki.cern.ch/twiki/bin/view/CMSPublic/PhysicsResultsSMP

H1 most recent αs extraction from inclusive and multjet cross-section. Best precision is reached from fit to normalised multijet cross sections:

0.0036 (scale)

exp. unc.0.7%

C.Roda – Universita` & INFN Pisa

s measurement3

CMS-PAS-SMP-12-028 CMS-PAS-SMP-12-027 arXiv 1406:470

αs measurement

World average (2014)

αs(MZ)= 0.1185 ± 0.0006 (0.5%)

CMS Most recent: inclusive jet (5%)

https://twiki.cern.ch/twiki/bin/view/CMSPublic/PhysicsResultsSMP

H1 most recent αs extraction from inclusive and multjet cross-section. Best precision is reached from fit to normalised multijet cross sections:

All measurements consistent with world average

Fantastic proof of αs(Q) running up to the TeV region

0.0036 (scale)

exp. unc.0.7%

C.Roda – Universita` & INFN Pisa

s measurement4

CMS-PAS-SMP-12-028 CMS-PAS-SMP-12-027 arXiv 1406:470

αs measurement

World average (2014)

αs(MZ)= 0.1185 ± 0.0006 (0.5%)

CMS Most recent: inclusive jet (5%)

https://twiki.cern.ch/twiki/bin/view/CMSPublic/PhysicsResultsSMP

H1 most recent αs extraction from inclusive and multjet cross-section. Best precision is reached from fit to normalised multijet cross sections:

All measurements consistent with world average

Fantastic prove of αs(Q) running up to the TeV region

0.0036 (scale)

exp. unc.0.7%

C.Roda – Universita` & INFN Pisa

parton distribution functions
Parton Distribution Functions

C.Roda – Universita` & INFN Pisa

pdf @ hera zeus h1

H1prelim14-041; ZEUS-prel-14-005

PDF @ HERA (ZEUS+H1)
  • HERA – most important data to measure the PDF
  • HERAPDF are based solely on the HERA ep data

e+p - NC

HERAPDF2.0 set recently obtained: use the full HERAI and HERAII dataset

Larger HERAII lumi yields significant improvement in precision at high x, Q2 region

  • Consistent data
  • Large reduction in uncertainties

C.Roda – Universita` & INFN Pisa

pdf hera2 0 pdf set

H1prelim14-042 ZEUS-prel-14-007

PDF – HERA2.0 PDF set

How does HERAPDF1.5 compare to new 2.0 NNLO ?

  • Shapes are similar
  • Gluon and sea at low and high x have smaller uncertainty and they become slightly softer
  • Valence at high x has also smaller uncertainty

C.Roda – Universita` & INFN Pisa

the gluon pdf and input from lhc

CMS-PAS-SMP-12-028

The gluon PDF… and input from LHC

PDF fits using only data from experiments with lower momentum transfer than available at the LHC have large uncertainties for the LHC kinematic region.

Data from LHC start to be precise enough to be used for PDF constraint

C.Roda – Universita` & INFN Pisa

the gluon pdf and input from lhc1

CMS-PAS-SMP-12-028

The gluon PDF… and input from LHC

PDF fits using only data from experiments with lower momentum transfer than available at the LHC have large uncertainties for the LHC kinematic region.

Gluon PDF constraint from CMS with

7 TeV inclusive jet cross-section

Data from LHC start to be precise enough to be used for PDF constraint

  • CMS fit a harder gluon, with respect to the fit using HERA alone (same results from ATLAS on lower stat. sample)
  • • Fractional uncertainty is smaller at high x, partly due to increased prediction
  • • Measurements are systematic limited at lower jet pT, dominated by the JES uncertainty

C.Roda – Universita` & INFN Pisa

the gluon pdf and input from lhc2

CMS-PAS-SMP-12-028

The gluon PDF… and input from LHC

PDF fits using only data from experiments with lower momentum transfer than available at the LHC have large uncertainties for the LHC kinematic region.

Gluon PDF constraint from CMS with 7 TeV inclusive jet cross-section

Very active field more results expected soon…

Data from LHC start to be precise enough to be used for PDF constraint

  • CMS fit a harder gluon, with respect to the fit using HERA alone (same results from ATLAS on lower stat. sample)
  • • Fractional uncertainty is smaller at high x, partly due to increased prediction
  • • Measurements are systematic limited at lower jet pT, dominated by the JES uncertainty

C.Roda – Universita` & INFN Pisa

inclusive jet hf
Inclusive γ, γ+jet, γ+HF

C.Roda – Universita` & INFN Pisa

isolated photon production
Isolated photon production
  • Photon is used as clean/uncolored probe for underlying parton-parton interaction
  • Test pQCD but also sensitive to non-prompt photons produced in fragmentation processes
  • Provide information on PDFs

Tevatron

LHC – 14 TeV

C.Roda – Universita` & INFN Pisa

isolated photon production1

Phys.Rev.D 89, 052004 (2014) ATL-PHYS-PUB-2013-018

Isolated photon production

7 TeV

No γ from fragmentation

  • New measurement extend the range from 0.1-1TeV ET and 5 orders of magnitude
  • NLO prediction (Jetphox+MSTW or CT10) describe very well the data up to high ET
  • Data demonstrate the need to have fragmentation photon to describe the data

Data is also used to verify the sensitivity to the gluon-PDF and show some tensions with all PDFs expectially with ABM shows a too soft gluon-PDF.

Measurement limited by scale uncertainty, NNLO prediction would help.

C.Roda – Universita` & INFN Pisa

isolated photon production2

CMS-PAS-SMP-14-005

Isolated photon production

8 TeV

Njet ≥1

4 times more statistics  halving of statistical uncertainty

Comparison is at LO … but NLO is coming

  • New measurement extend the range from 0.1-1TeV ET and 5 orders of magnitude
  • NLO prediction (Jetphox+MSTW or CT10) describe very well the data up to high ET
  • Data demonstrate the need to have fragmentation photon to describe the data

Data is also used to verify the sensitivity to the gluon-PDF and show some tensions with all PDFs expectially with ABM shows a too soft gluon-PDF.

Measurement limited by scale uncertainty, NNLO prediction would help.

C.Roda – Universita` & INFN Pisa

bb cross section d0

Phys.Rev.D 89, 074001 (2014) FERMILAB-PUB-14-135-E

γ+bb cross-section – D0
  • Higher uncertainty in the prediction than for LF jets
  • Direct access to b-quark PDF
  • Isolation to limit photon from fragmentation
  • Very different process contribution for Tevatron and LHC
  • NLO calculation and kT factorization/NLO approach show good agreement with data.
  • NLO calculation has smaller scale uncertainty
  • PYTHIA fails both shape and rate
  • SHERPA fails at low pT

C.Roda – Universita` & INFN Pisa

w z jets
W/Z+jets

C.Roda – Universita` & INFN Pisa

a deep look at w jet atlas cms
A deep look at W+jet – ATLAS & CMS

A detailed comparison on a high statistics sample and in a large kinematics range  precious information to validate/tune the predictions.

Tested variables: 1st , 2nd, 3rd 4th-leading jet pT and η, HT,ST (Sum pT including or not lepton and neutrino), angular separation of jets, invariant mass of lead-subleading jets. Inclusive and exclusive distributions…

Predictions: NLO calculations, resummation calculations, MC generators NLO,LO + PS

C.Roda – Universita` & INFN Pisa

a deep look at w jet atlas cms1

CMS-PAS-SMP-12-023 ATLAS-CONF-2014-035

A deep look at W+jet – ATLAS & CMS

Jet multiplicity

C.Roda – Universita` & INFN Pisa

a deep look at w jet atlas cms2

CMS-PAS-SMP-12-023 ATLAS-CONF-2014-035

A deep look at W+jet – ATLAS & CMS

Jet multiplicity

Jet multiplicity well reproduced up to ≥7 jets on 5 order of magnitudes !

Best overall description NLO+PS (BlackHat+Sherpa) with some exception for high HT, ST distributions.

C.Roda – Universita` & INFN Pisa

double differential z jet @ 8 tev

CMS-PAS-SMP-14-009

Double differential Z+jet @ 8 TeV

30

First double differential measurement Z+jet

Jet up to |η|<4.7 – 30 < pT<550 GeV

Largest experimental uncertainty JES

Predictions: MadGraph norm.NNLO / Sherpa2 (NLO 1j,2j)

C.Roda – Universita` & INFN Pisa

double differential z jet @ 8 tev1

CMS-PAS-SMP-14-009

Double differential Z+jet @ 8 TeV

First double differential measurement Z+jet

Jet up to |η|<4.7 – 30 < pT<550 GeV

Largest experimental uncertainty JES

Predictions: MadGraph norm.NNLO / Sherpa2 (NLO 1j,2j /LO<=4j)

MadGraph overshoot for pTjet > 100 GeV

Reasonable description from Sherpa2, some regions to investigate

C.Roda – Universita` & INFN Pisa

boson jets production ratios

CMS-PAS-SMP-14-005 ATLAS-CONF-2014-034

Boson+jets production ratios

Ratios allows to reduce experimental systematic uncertainties

Ratio is studied in inclusive and exclusive distributions for Njet≥3

C.Roda – Universita` & INFN Pisa

boson jets production ratios1

CMS-PAS-SMP-14-005 ATLAS-CONF-2014-034

Boson+jets production ratios

Ratios allows to reduce experimental systematic uncertainties

Ratio is studied in inclusive and exclusive distributions of Njet=3

W+jet/Z+jet vs pT jet leading

Njet≥1 - 7 TeV

C.Roda – Universita` & INFN Pisa

boson jets production ratios2

CMS-PAS-SMP-14-005 ATLAS-CONF-2014-034

Boson+jets production ratios

Ratios allows to reduce experimental systematic uncertainties

Ratio is studied in inclusive and exclusive distributions of Njet=3

W+jet/Z+jet vs pT jet leading

Njet≥1 - 7 TeV

Z+jet/γ+jet vs pT boson

Njet≥1 - 8 TeV

C.Roda – Universita` & INFN Pisa

boson jets production ratios3

CMS-PAS-SMP-14-005 ATLAS-CONF-2014-034

Boson+jets production ratios

Ratios allows to reduce experimental systematic uncertainties

Ratio is studied in inclusive and exclusive distributions of Njet=3

W+jet/Z+jet vs pT jet leading

Njet≥1 - 7 TeV

Z+jet/γ+jet vs pT boson

Njet≥1 - 8 TeV

Flattens at high transferred transverse momentum

LO prediction 10% off in norm / good in shape

Detailed test of ratios with respect to NLO/LO predictions

C.Roda – Universita` & INFN Pisa

w z hf
W/Z+HF

C.Roda – Universita` & INFN Pisa

w charm lhc

JHEP 05 (2014) 068 JHEP 02(2014)013

W+charm - LHC
  • Probes the strange content of the proton
  • contribution from d quark about ~10% (Cabibbo suppressed)
  • Different PDFs assume different level of suppression of s-quark w.r. to d-quark sea.

C.Roda – Universita` & INFN Pisa

w c lhc

JHEP05(2014)068 arXiv:1402.6263 arXiv:1312.6283

W+c – LHC

ATLAS  no s-sea suppression w.r. to light flavour sea

w c lhc1

JHEP05(2014)068 arXiv:1402.6263 arXiv:1312.6283

W+c – LHC

ATLAS  no s-sea suppression w.r. to light flavour sea

CMS  consistent with s-sea suppression

w c lhc2

JHEP05(2014)068 arXiv:1402.6263 arXiv:1312.6283

W+c – LHC

ATLAS  no s-sea suppression w.r. to light flavour sea

CMS  consistent with s-sea suppression

Fit s-quark PDF:

HERAPDF including W+c data

w z d production cdf

CDF note 11087

W/Z+D* production - CDF
  • Charm identified reconstructing:
    • D* D0 π  Kπ π
  • Measure
  • Separate contributions process comparing same and opposite sign productions and using difference in pT(D∗) distributions: Wc (14±6)%, Wg(cc) (73±8)% , Wg(bb) (13±5)%

PYTHIA6.2+CTEQ5L in good agreement with data

C.Roda – Universita` & INFN Pisa

z b bb cross sections atlas

STDM-2012-15

Z+b/bb cross-sections - ATLAS

5FNS

4FNS and 5FNS

Test of NLO/LO multileg predictions

Test of Number Flavour schemes (4NFS / 5NFS)

C.Roda – Universita` & INFN Pisa

z b bb cross sections atlas1

STDM-2012-15

Z+b/bb cross-sections - ATLAS

5FNS

4FNS and 5FNS

Test of NLO/LO multileg predictions

Test of Number Flavour schemes (4NFS / 5NFS)

PDF

MCFM agrees with data within uncertainties

NLO is still too affected by scale uncertainty to be sensitive to PDFs

Double differential distributions are also compared to different predictions

C.Roda – Universita` & INFN Pisa

z b bb cross sections atlas2

STDM-2012-15

Z+b/bb cross-sections - ATLAS

5FNS

4FNS and 5FNS

Test of NLO/LO multileg predictions

Test of Number Flavour schemes (4NFS / 5NFS)

4FNS

5FNS

MCFM agrees well with data

NLO is still too affected by scale uncertainty to be sensitive to PDFs

Double differential distributions are also compared to different predictions

C.Roda – Universita` & INFN Pisa

and last but not least
and last but not least …

C.Roda – Universita` & INFN Pisa

total cross section measurement

ATLAS-CONF-2014-040

Total cross-section measurement
  • Basic principle - use Optical theorem to calculate the total cross-section

Measure the differential elastic cross section in the 4-momentum transfer variable t and the extrapolate to t0 to determine the total cross section.

Data are collected with

the ATLAS-ALFA Roman

Pot detector in a

dedicated run.

C.Roda – Universita` & INFN Pisa

total cross section measurement1

ATLAS-CONF-2014-040

Total cross-section measurement
  • Basic principle - use Optical theorem to calculate the total cross-section

Measure the differential elastic cross section in the 4-momentum transfer variable t and the extrapolate to t0 to determine the total cross section.

conclusions
Conclusions
  • QCD tested in new kinematic regions, with exclusive and inclusive measurement, often differential or double differential measurements !
  • In many cases the experimental uncertainty is at the level or smaller than theoretical uncertainty
  • The new tools for theoretical predictions have proved to provide a reliable description of data for most of the measurements
  • αsrunning proved up to TeV scale
  • A lot of information to be improve PDF description

C.Roda – Universita` & INFN Pisa

conclusions1
Conclusions
  • QCD tested in new kinematic regions, with exclusive and inclusive measurement, often differential or double differential measurements !
  • In many cases the experimental uncertainty is at the level or smaller than theoretical uncertainty
  • The new tools for theoretical predictions have proved to provide a reliable description of data for most of the measurements
  • αsrunning proved up to TeV scale
  • A lot of information to be improve PDF description

pQCD is doing very well up to now …

we are ready for the new challenge at √s = 13 TeV

C.Roda – Universita` & INFN Pisa

conclusions2
Conclusions
  • QCD tested in new kinematic regions, with exclusive and inclusive measurement, often differential or double differential measurements !
  • In many cases the experimental uncertainty is at the level or smaller than theoretical uncertainty
  • The new tools for theoretical predictions have proved to provide a reliable description of data for most of the measurements
  • αsrunning proved up to TeV scale
  • A lot of information to be improve PDF description

pQCD is doing very well up to now …

we are ready for the new challenge at √s = 13 TeV

Many thanks to: Sasha Glazov, Maxime Gouzevitch, Ashish Kumar, Christina Mesropian, Alexander Savin, Alessandro Tricoli, Stefan Schmitt, Matthew Wing.

C.Roda – Universita` & INFN Pisa

back up
Back up

C.Roda – Universita` & INFN Pisa

combined fit using lhc jet data

CMS-PAS-SMP-12-028 EPJ (2013) 73 2509

Combined fit using LHC jet data

Gluon PDF constraint from CMS with 7 TeV inclusive jet cross-section

ATLAS uses cs ratio (2.7 TeV /7 TeV) to reduce systematic uncertainty

  • Both ATLAS and CMS fit a harder gluon, with respect to the fit using HERA alone
  • • Fractional uncertainty is smaller at high x, partly due to increased prediction
  • • Measurements are systematic limited at lower jet PT, dominated by the Jet Energy Scale uncertainty

C.Roda – Universita` & INFN Pisa

three jet cross sections
Three jet cross-sections

C.Roda – Universita` & INFN Pisa

three jet cross section
Three jet cross-section

C.Roda – Universita` & INFN Pisa

three jet cross section1
Three jet cross-section

C.Roda – Universita` & INFN Pisa

inclusive jet cross section
Inclusive jet cross-section

C.Roda – Universita` & INFN Pisa

inclusive jet cross section1
Inclusive jet cross-section

C.Roda – Universita` & INFN Pisa

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