QCD@LHC 2015 London, September 1, 2015 Rick Field – Florida/CDF/CMSPage 1 Outline of Talk CMS at the LHC CDF “Tevatron Energy Scan” 300 GeV, 900 GeV, 1.96

QCD@LHC 2015 London, September 1, 2015

Rick Field – Florida/CDF/CMS Page 1

Outline of Talk

CMS at the LHC

CDF “Tevatron Energy Scan”300 GeV, 900 GeV, 1.96 TeV

900 GeV, 7 TeV, 13 TeV

QCD@LHC 2015QCD@LHC 2015

Rick FieldUniversity of Florida

Proton AntiProton

PT(hard)

Outgoing Parton

Outgoing Parton

Underlying Event Underlying Event

Initial-State Radiation

Final-State Radiation

Soft QCD and MPI

CMS UE Tunes: Two PYTHIA 6 tunes, three PYTHIA 8 tunes, and one HERWIG++ tune from the CMS “Physics Comparisons & Generator Tunes” subgroup.

UE Studies: Past, present, and future.

Predictions at 13 TeV: Compare the CMS PYTHIA 8 tunes with the Skands Monash tune and the PYTHIA 6 Tune Z2* at 13 TeV.

MB & UE Data 13 TeV: Look at the early MB data from CMS and ATLAS and the early UE data from ATLAS.

The Energy Dependence of the UE: Detailed look at the energy dependence of the UE and the extrapolation to 13 TeV.



The Inelastic Non-Diffractive The Inelastic Non-Diffractive Cross-SectionCross-Section

Proton Proton

Proton Proton +

Proton Proton

Proton Proton

+

Proton Proton +

+ …

“Semi-hard” parton-parton collision(pT < ≈2 GeV/c)

Occasionally one of the parton-parton collisions is hard(pT > ≈2 GeV/c)

Majority of “min-bias” events!

Multiple-parton interactions (MPI)!



The “Underlying Event”The “Underlying Event”

Proton Proton

Select inelastic non-diffractive events that contain a hard scattering

Proton Proton

Proton Proton +

Proton Proton

+ + …

“Semi-hard” parton-parton collision(pT < ≈2 GeV/c)

Hard parton-parton collisions is hard(pT > ≈2 GeV/c) The “underlying-event” (UE)!

Multiple-parton interactions (MPI)!

Given that you have one hard scattering it is more probable to have MPI! Hence, the UE has more activity than “min-bias”.

1/(pT)4→ 1/(pT2+pT0

2)2

pT0(Ecm)=pT0Ref × (Ecm/EcmRef)ecmPow



Traditional ApproachTraditional Approach

Look at charged particle correlations in the azimuthal angle relative to a leading object (i.e. CaloJet#1, ChgJet#1, PTmax, Z-boson). For CDF PTmin = 0.5 GeV/c cut = 1.0 or 0.8.

Charged Particle Correlations PT > PTmin || < cut

Leading Object Direction

“Toward”

“Transverse” “Transverse”

“Away”

Define || < 60o as “Toward”, 60o < || < 120o as “Transverse”, and || > 120o as “Away”.

Leading Calorimeter Jet or Leading Charged Particle Jet or

Leading Charged Particle orZ-Boson

-cut +cut

2

0

Leading Object

Toward Region

Transverse Region

Transverse Region

Away Region

Away Region

All three regions have the same area in - space, × = 2cut×120o = 2cut×2/3. Construct densities by dividing by the area in - space.

Charged Jet #1Direction


“Toward”

“Away”

“Toward-Side” Jet

“Away-Side” Jet

“Transverse” region very sensitive to the “underlying event”!

CDF Run 1 Analysis



Early Studies of the UEEarly Studies of the UE

DPF 2000: My first presentation on the “underlying event”! First CDF UE Studies

Rick Field Wine & Cheese TalkOctober 4, 2002



My First Talk on the UEMy First Talk on the UE

My first look at the “underlying event plateau”!

Need to “tune” the QCD MC models!



UE PublicationsUE Publications

Publications on the “underlying event” (2000-2015).

"Underlying Event" Publications

0

10

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30

20002001

20022003

20042005

20062007

20082009

20102011

20122013

20142015

Year

Nu

mb

er

Other

CDF

The Underlying Event in Large Transverse Momentum Charged Jet and

Z−boson Production at CDF, R. Field, published in the proceedings of DPF 2000. Charged Jet Evolution and the Underlying Event in

Proton-Antiproton Collisions at 1.8 TeV,CDF Collaboration, Phys. Rev. D65 (2002) 092002.

Gavin Salam!

Perugia Tunes, Peter Skands!

Many LHC UE Studies

HERWIG++ UE Tune, M. Seymour and A. Siódmok!

Monash Tune,Peter Skands!

A Study of the Energy Dependence of the Underlying Event in Proton-Antiproton Collisions,

CDF Collaboration, submitted to Phys. Rev. D. (August 24, 2015)!



Proton AntiProton

PT(hard)

Outgoing Parton

Outgoing Parton




Sorry to be so slow!!

Latest CDF UE PublicationLatest CDF UE Publication

CDF Run 2Tevatron Energy Scan

300 GeV, 900 GeV, 1.96 TeV

The goal is to produce data (corrected to the particle level) that can be used by the theorists to tune and improve the QCD Monte-Carlo models that are used to simulate hadron-hadron collisions.

Submitted to PRD

http://arxiv.org/abs/1508.05340



UE ObservablesUE Observables“Transverse” Charged Particle Density: Number of charged particles

(pT > 0.5 GeV/c, || < cut) in the “transverse” region as defined by the leading charged particle, PTmax, divided by the area in - space, 2cut×2/3, averaged over all events with at least one particle with pT > 0.5 GeV/c, || < cut.

PTmax Direction

“Toward”


“Away”

“Transverse” Charged PTsum Density: Scalar pT sum of the charged particles (pT > 0.5 GeV/c, || < cut) in the “transverse” region as defined by the leading charged particle, PTmax, divided by the area in - space, 2cut×2/3, averaged over all events with at least one particle with pT > 0.5 GeV/c, || < cut.

“Transverse” Charged Particle Average PT: Event-by-event <pT> = PTsum/Nchg for charged particles (pT > 0.5 GeV/c, || < cut) in the “transverse” region as defined by the leading charged particle, PTmax, averaged over all events with at least one particle in the “transverse” region with pT > 0.5 GeV/c, || < cut.

Zero “Transverse” Charged Particles: If there are no charged particles in the “transverse” region then Nchg and PTsum are zero and one includes these zeros in the average over all events with at least one particle with pT > 0.5 GeV/c, || < cut. However, if there are no charged particles in the “transverse” region then the event is not used in constructing the “transverse” average pT.



UE ObservablesUE Observables“transMAX” and “transMIN” Charged Particle Density: Number of

charged particles (pT > 0.5 GeV/c, || < 0.8) in the the maximum (minimum) of the two “transverse” regions as defined by the leading charged particle, PTmax, divided by the area in - space, 2cut×2/6, averaged over all events with at least one particle with pT > 0.5 GeV/c, || < cut.

PTmax Direction

“Toward”

“TransMAX” “TransMIN”

“Away”

“transMAX” and “transMIN” Charged PTsum Density: Scalar pT sum of charged particles (pT > 0.5 GeV/c, || < 0.8) in the the maximum (minimum) of the two “transverse” regions as defined by the leading charged particle, PTmax, divided by the area in - space, 2cut×2/6, averaged over all events with at least one particle with pT > 0.5 GeV/c, || < cut.

Note: The overall “transverse” density is equal to the average of the “transMAX” and “TransMIN” densities. The “TransDIF” Density is the “transMAX” Density minus the “transMIN” Density

“Transverse” Density = “transAVE” Density = (“transMAX” Density + “transMIN” Density)/2

“TransDIF” Density = “transMAX” Density - “transMIN” Density



““transMIN” & “transDIF”transMIN” & “transDIF”The “toward” region contains the leading “jet”, while the “away”

region, on the average, contains the “away-side” “jet”. The “transverse” region is perpendicular to the plane of the hard 2-to-2 scattering and is very sensitive to the “underlying event”. For events with large initial or final-state radiation the “transMAX” region defined contains the third jet while both the “transMAX” and “transMIN” regions receive contributions from the MPI and beam-beam remnants. Thus, the “transMIN” region is very sensitive to the multiple parton interactions (MPI) and beam-beam remnants (BBR), while the “transMAX” minus the “transMIN” (i.e. “transDIF”) is very sensitive to initial-state radiation (ISR) and final-state radiation (FSR).

“TransDIF” density more sensitive to ISR & FSR.

PTmax Direction


“Toward”

“Away”

“Toward-Side” Jet

“Away-Side” Jet

Jet #3

“TransMIN” density more sensitive to MPI & BBR.

0 ≤ “TransDIF” ≤ 2×”TransAVE”

“TransDIF” = “TransAVE” if “TransMIX” = 3×”TransMIN”



““transMAX/MIN” NchgDentransMAX/MIN” NchgDen

Corrected CMS data at 7 TeV and CDF data at 1.96 TeV, 900 GeV, and 300 GeV on the charged particle density in the “transMAX”, “transMIN”, and “transDIF” regions as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 0.8. The data are corrected to the particle level with errors that include both the statistical error and the systematic uncertainty.

"TransMAX" Charged Particle Density: dN/dd

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7 TeV

RDF Preliminary Corrected Data

"TransMIN" Charged Particle Density: dN/dd

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"TransDIF" Charged Particle Density: dN/dd

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CDF

CDFCDF

CMS



““transMAX/MIN” PTsumDentransMAX/MIN” PTsumDen

Corrected CDF data at 1.96 TeV, 900 GeV, and 300 GeV on the charged PTsum density in the “transMAX”, “transMIN”, and “transDIF” regions as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 0.8. The data are corrected to the particle level with errors that include both the statistical error and the systematic uncertainty.

"TransMAX" Charged PTsum Density: dPT/dd

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"TransMIN" Charged PTsum Density: dPT/dd

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7 TeVRDF Preliminary

Corrected Data

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300 GeV

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"TransDIF" Charged PTsum Density: dPT/dd

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1.96 TeV

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““transMAX” NchgDen vs EtransMAX” NchgDen vs Ecmcm

Corrected CMS data at 7 TeV and CDF data at 1.96 TeV, 900 GeV, and 300 GeV on the charged particle density in the “transMAX” region as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 0.8. The data are corrected to the particle level with errors that include both the statistical error and the systematic uncertainty.

Corrected CMS and CDF data on the charged particle density in the “transMAX” region as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 0.8 with 5 < PTmax < 6 GeV/c. The data are plotted versus the center-of-mass energy (log scale).


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““transMIN” NchgDen vs EtransMIN” NchgDen vs Ecmcm

Corrected CMS data at 7 TeV and CDF data at 1.96 TeV, 900 GeV, and 300 GeV on the charged particle density in the “transMIN” region as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 0.8. The data are corrected to the particle level with errors that include both the statistical error and the systematic uncertainty.

Corrected CMS and CDF data on the charged particle density in the “transMIN” region as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 0.8 with 5 < PTmax < 6 GeV/c. The data are plotted versus the center-of-mass energy (log scale).


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““Transverse” NchgDen vs ETransverse” NchgDen vs Ecmcm

Corrected CMS data at 7 TeV and CDF data at 1.96 TeV, 900 GeV, and 300 GeV on the charged particle density in the “transMAX” and “transMIN” regions as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 0.8 with 5 < PTmax < 6 GeV/c. The data are plotted versus the center-of-mass energy (log scale).

Ratio of CMS data at 7 TeV and CDF data at 1.96 TeV, 900 GeV, and 300 GeV to the value at 300 GeV for the charged particle density in the “transMAX” and “transMIN” regions as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 0.8 with 5 < PTmax < 6 GeV/c. The data are plotted versus the center-of-mass energy (log scale).

"Transverse" Charged Particle Density: dN/dd

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"TransMIN"

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"Transverse" Charged Particle Density Ratio

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"TransMIN"

"TransMAX"

5.0 < PTmax < 6.0 GeV/c

Divided by 300 GeV Value



““Transverse” NchgDen vs ETransverse” NchgDen vs Ecmcm

Corrected CMS data at 7 TeV and CDF data at 1.96 TeV, 900 GeV, and 300 GeV on the charged particle density in the “transAVE” and “transDIF” regions as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 0.8 with 5 < PTmax < 6 GeV/c. The data are plotted versus the center-of-mass energy (log scale).

Ratio of CMS data at 7 TeV and CDF data at 1.96 TeV, 900 GeV, and 300 GeV to the value at 300 GeV for the charged particle density in the “transAVE” and “transDIF” regions as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 0.8 with 5 < PTmax < 6 GeV/c. The data are plotted versus the center-of-mass energy (log scale).

"Transverse" Charged Particle Density: dN/dd

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"TransDIF"

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““TransMIN/DIF” vs ETransMIN/DIF” vs Ecmcm

Ratio of CMS data at 7 TeV and CDF data at 1.96 TeV, 900 GeV, and 300 GeV to the value at 300 GeV for the charged particle density in the “transMIN”, and “transDIF” regions as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 0.8 with 5 < PTmax < 6 GeV/c. The data are plotted versus the center-of-mass energy (log scale).

Ratio of CMS data at 7 TeV and CDF data at 1.96 TeV, 900 GeV, and 300 GeV to the value at 300 GeV for the charged PTsum density in the “transMIN”, and “transDIF” regions as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 0.8 with 5 < PTmax < 6 GeV/c. The data are plotted versus the center-of-mass energy (log scale).


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"TransDIF"

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First Time SeenThe “transMIN” (MPI-BBR component) increases

much faster with center-of-mass energy than the “transDIF” (ISR-FSR component)!



Proton AntiProton

PT(hard)

Outgoing Parton

Outgoing Parton




Sorry to be so slow!!

CMS Tuning PublicationCMS Tuning Publication

http://arxiv.org/abs/soon!

CMS at the LHC

900 GeV, 2.96 TeV, 7 TeV, 8 TeV, 13 TeV

To be submitted to JHEP



UE Tunes and MBUE Tunes and MB

Proton Proton

Proton Proton +

Proton Proton

Proton Proton

+

Proton Proton +

+ …

“Underlying Event”

“Min-Bias” (ND)

Fit the “underlying event” in a hard

scattering process.

Predict MB (ND)!

1/(pT)4→ 1/(pT2+pT0

2)2

Allow primary hard-scattering to go to pT = 0 with same cut-off!

Single Diffraction

M

Double Diffraction

M1 M2

“Min-Bias” (add single & double diffraction)

Predict MB (IN)!



DPS: Double Parton Scattering

UE Tunes and DPSUE Tunes and DPS

Proton Proton

Most of the time MPI are much “softer” than the primary “hard” scattering, however, occasionally two “hard” 2-to-2 parton scatterings can occur within the same hadron-hadron. This is referred to as double parton scattering (DPS).

1/(pT)4→ 1/(pT2+pT0

2)2

“Underlying Event”“Underlying Event”

Fit the “underlying event” in a hard

scattering process.

Predict DPS sensitive observables!



CMS UE TunesCMS UE Tunes

PTmax Direction

“Toward”


“Away”

PYTHIA 6.4 Tune CUETP6S1-CTEQ6L: Start with Tune Z2*-lep and tune to the CDF PTmax “transMAX” and “transMIN” UE data at 300 GeV, 900 GeV, and 1.96 TeV and the CMS PTmax “transMAX” and “transMIN” UE data at 7 TeV.

PYTHIA 8 Tune CUETP8S1-CTEQ6L: Start with Corke & Sjöstrand Tune 4C and tune to the CDF PTmax “transMAX” and “transMIN” UE data at 900 GeV, and 1.96 TeV and the CMS PTmax “transMAX” and “transMIN” UE data at 7 TeV. Exclude 300 GeV data.

PYTHIA 8 Tune CUETP8S1-HERAPDF1.5LO: Start with Corke & Sjöstrand Tune 4C and tune to the CDF PTmax “transMAX” and “transMIN” UE data at 900 GeV, and 1.96 TeV and the CMS PTmax “transMAX” and “transMIN” UE data at 7 TeV. Exclude 300 GeV data.

PYTHIA 8 Tune CUETP8M1-NNPDF2.3LO: Start with the Skands Monash-NNPDF2.3LO tune and tune to the CDF PTmax “transMAX” and “transMIN” UE data at 900 GeV, and 1.96 TeV and the CMS PTmax “transMAX” and “transMIN” UE data at 7 TeV. Exclude 300 GeV data.

HERWIG++ Tune CUETHS1-CTEQ6L: Start with the Seymour & Siódmok UE-EE-5C tune and tune to the CDF PTmax “transMAX” and “transMIN” UE data at 900 GeV, and 1.96 TeV and the CMS PTmax “transMAX” and “transMIN” UE data at 7 TeV.

PYTHIA 6.4 Tune CUETP6S1-HERAPDF1.5LO: Start with Tune Z2*-lep and tune to the CDF PTmax “transMAX” and “transMIN” UE data at 300 GeV, 900 GeV, and 1.96 TeV and the CMS PTmax “transMAX” and “transMIN” UE data at 7 TeV.

See talk on Saturday morningby Frank Siegert entitled,

“Overview of MC Tuning to LHC Data”



CUETP8S1-CTEQ6LCUETP8S1-CTEQ6L

CMS data at 7 TeV and CDF data at 1.96 TeV, 900 GeV, and 300 GeV on the charged particle density in the “transAVE” region as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 0.8. The data are compared with PYTHIA 8 Tune CUETP8S1-CTEQ6L (excludes 300 GeV in fit).

"TransAVE" Charged Particle Density

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CMS Tune CUETP8S1-CTEQ6L


300 GeV

900 GeV

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7 TeV

CMS data at 7 TeV and CDF data at 1.96 TeV, 900 GeV, and 300 GeV on the charged particle density in the “transAVE” region as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 0.8. The data are compared with PYTHIA 6.4 Tune Z2*.


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7 TeVTune Z2*-CTEQ6L

Exclude 300 GeV data!



CUETP8M1-NNPDF2.3LOCUETP8M1-NNPDF2.3LO

CMS data at 7 TeV and CDF data at 1.96 TeV, 900 GeV, and 300 GeV on the charged particle density in the “transAVE” region as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 0.8. The data are compared with the PYTHIA 8 Tune Monash-NNPDF2.3LO.

CMS data at 7 TeV and CDF data at 1.96 TeV, 900 GeV, and 300 GeV on the charged particle density in the “transAVE” region as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 0.8. The data are compared with the PYTHIA 8 Tune CUETP8M1-NNPDF2.3LO (excludes 300 GeV in fit).


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Energy DependenceEnergy Dependence"TransAVE" Charged Particle Density: dN/dd

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CMS solid dotsCDF solid squares

Tune Z2*-CTEQ6L (solid line)

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Tune Z2*-CTEQ6L (green line)CUETP8S1-CTEQ6L (black line)Monash-NNPDF2.3LO (red line)

CUETP8M1-NNPDF2.3LO (blue line) 13 TeV



Predictions at 13 TeVPredictions at 13 TeV"TransMAX" Charged Particle Density

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"TransMIN" Charged Particle Density

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"TransMAX" Charged PTsum Density

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"TransMIN" Charged PTsum Density

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Predictions at 13 TeVPredictions at 13 TeV"TransAVE" Charged Particle Density

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"TransDIF" Charged Particle Density

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"TransAVE" Charged PTsum Density

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"TransDIF" Charged PTsum Density

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Predictions at 13 TeVPredictions at 13 TeV

CMS data at 7 TeV and CDF data at 1.96 TeV, 900 GeV, and 300 GeV on the charged particle density in the “transAVE” region as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 0.8. The data are compared with PYTHIA 6 Tune Z2* and PYTHIA 8 Tune CUETP8S1, Tune Monash, and Tune CUETP8M1.

CMS and CDF data on the charged particle density in the “transAVE” region as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 0.8 with 5 < PTmax < 6 GeV/c. The data are plotted versus the center-of-mass energy (log scale). The data are compared with PYTHIA 6 Tune Z2* and PYTHIA 8 Tune CUETP8S1, Tune Monash, and Tune CUETP8M1.


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Predictions at 13 TeVPredictions at 13 TeV

CMS data at 7 TeV and CDF data at 1.96 TeV, 900 GeV, and 300 GeV on the charged PTsum density in the “transAVE” region as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 0.8. The data are compared with PYTHIA 6 Tune Z2* and PYTHIA 8 Tune CUETP8S1, Tune Monash, and Tune CUETP8M1.

CMS and CDF data on the charged PTsum density in the “transAVE” region as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 0.8 with 5 < PTmax < 6 GeV/c. The data are plotted versus the center-of-mass energy (log scale). The data are compared with PYTHIA 6 Tune Z2* and PYTHIA 8 Tune CUETP8S1, Tune Monash, and Tune CUETP8M1.

"TransAVE" Charged PTsum Density: dPT/dd

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MB at 13 TeV: dN/dMB at 13 TeV: dN/d

CMS UE Tune CUETP8S1-HERAPDF1.5LO.

EPOS LHC

HERWIG++

The UE tune do a fairly good jobpredicting the MB data.

Do not need separate MB tunes!



ATLAS 13 TeV UE DataATLAS 13 TeV UE Data

Detector Level Detector Level

ATLAS data at 13 TeV on the charged particle density (keft) and charged PTsum density in the “transAVE” region as defined by the leading charged particle for charged particles with pT > 0.5 GeV/c and || < 2.5. The data are uncorrected and compared with the MC models after detector simulation.

Monash doing well except the turn on region! Very strange behavior by HERWIG++

in the turn on region!

EPOS does a poor job on the UE!




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More 13 TeVPredictionsMore 13 TeVPredictions"TransAVE" Charged Particle Density

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Very strange behavior by CUETHS1 in the turn on region!


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CUETP8M1-NNPDF2.3LO (blue line)CUETHS1-CTEQ6L (brown line)




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1.96 TeV

300 GeV

900 GeV

7 TeV

13 TeV RDF Preliminary

Corrected Data

““Tevatron” to the LHCTevatron” to the LHC

CDF

CDF

CDF

Mapping out the Energy Dependence of the UE

(300 GeV, 900 GeV, 1.96 TeV, 7 TeV, 13 TeV)

My dream!

CMS

Fake data generated by Rick using the Monash tune with the statistics we currently have at CMS!




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900 GeV

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13 TeV RDF Preliminary

Corrected Data

““Tevatron” to the LHCTevatron” to the LHC

CDF

CDF

CDF

Mapping out the Energy Dependence of the UE

(300 GeV, 900 GeV, 1.96 TeV, 7 TeV, 13 TeV)

My dream!

CMS

13 TeV UE data coming soon from both ATLAS and CMS!

Coming soon!



UE@CMS 13 TeVUE@CMS 13 TeV

ChgJet#1 Direction

“Toward”


“Away”

Measure the “Underlying Event” at 13 TeV at CMS

UE@13TeVLivio Fano' (University of Perugia)

Diego Ciangottini (University of Perugia)Rick Field (University of Florida)Doug Rank (University of Florida)

Sunil Bansal (Panjab University Chandigarh)

UE&MB@CMSUE&MB@CMS

University of Perugia

PTmax Direction

“Toward”


“Away”

Measure the UE observables as defined by the leading charged particle jet, chgjet#1, for charged particles with pT > 0.5 GeV/c and || < 2.0.

Measure the UE observables as defined by the leading charged particle, PTmax, for charged particles with pT > 0.5 GeV/c and || < 2.0 and || < 0.8.

Proton Proton

PT(hard)

Outgoing Parton

Outgoing Parton




Livio & Rick were part of the CMS Run 1 UE&MB team!

Sorry to be slow! We hope to have the CMS “Common Plots” finished for

the LPCC UE&MB meeting on November 19 and 20!

Documents

QCD@LHC 2015 London, September 1, 2015 Rick Field – Florida/CDF/CMSPage 1 Outline of Talk CMS at the LHC CDF “Tevatron Energy Scan” 300 GeV, 900 GeV, 1.96