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MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 1
Outline of Talk
CMS at the LHCCDF “Tevatron Energy Scan”300 GeV, 900 GeV, 1.96 TeV 900 GeV, 7 & 8 TeV
MPI@LHC 2014MPI@LHC 2014Rick Field
University of Florida
Proton AntiProton
PT(hard)
Outgoing Parton
Outgoing Parton
Underlying EventUnderlying Event
Initial-State Radiation
Final-State Radiation
CMS UE and MB Tunes
CMS UE Tunes: Three PYTHA 8 tunes (CTEQ6L, HERALOPDF, NNPDF2.3LO) and one PYTHIA 6 tune (CTEQ6L) from the CMS “Physics Comparisons & Generator Tunes” subgroup.UE Observables: “transMAX”,”transMIN”, “transAVE”, “transDIF”.
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 Studies: Look at dN/dη and the energy flow in the forward region.
The Energy Dependence of the UE: Detailed look at the energy dependence of the UE and the extrapolation to 13 TeV.
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 2
CMS UE TunesCMS UE TunesPYTHIA 6.4 Tune Z2*- CTEQ6L: Start with Tune Z2 and tune to the CMS leading charged particle jet UE data at 900 GeV and 7 TeV. Improved version of Tune Z2.
PTmax Direction Δφ
“Toward”
“TransMAX” “TransMIN”
“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. Improved version of Tune Z2*.
PYTHIA 8 Tune CUETP8S1-CTEQ6L: Start with 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. Improved version of Tune 4C.
PYTHIA 8 Tune CUETP8S1-HERALOPDF: Start with 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. Improved version of Tune 4C.
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 TeVand the CMS PTmax “transMAX” and “transMIN” UE data at 7 TeV. Exclude 300 GeV data.
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 3
CMS CMS Tune CUETP8S1Tune CUETP8S1--CTEQ6L CTEQ6L
18001800ecmRef
0.210570.19ecmPow
3
0.50
2.0
1.0
0.4
0.4
0.1383
0.137
0.135
0.135
1.5
2.0
2.085
CTEQ6L
4C
3Tune:ee
0.50BeamRemnants:primordialKTsoft
2.0BeamRemnants:primordialKThard
1.0BeamRemnants:halfScaleForKT
0.4TimeShower:pTminChgQ
0.4TimeShower:pTmin
0.1383TimeShower:alphaSvalue
0.137SpaceShower:alphaSvalue
0.135SigmaProcess:alphaSvalue
0.135MultipartonInteractions:alphaSvalue
3.31257reconnectRange
1.60889expPow
2.1006pT0Ref
CTEQ6LPDF
CMS1
PYTHIA 8 Tunes: Corke & Sjöstrand Tune 4C-CTEQ6L and CMS Tune CUETP8S1-CTEQ6L (CMS1).
CMS Tune CUETP8S1-CTEQ6LpT0Ref = 2.1006ecmPow = 0.21057ecmRef = 1800
3.18513
2.7967
2.1391.96
1.8150.9
1.4400.3
pT0 (GeV/c)Ecm (TeV)
pT0(Ecm)=pT0Ref × (Ecm/ecmRef)ecmPow
Start with Tune 4C and vary 4 parameters!
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 4
CMS Tune CMS Tune MonashMonashStarStar
70007000ecmRef
0.252080.2150ecmPow
77Tune:ee
0.90.9BeamRemnants:primordialKTsoft
1.81.8BeamRemnants:primordialKThard
1.51.5BeamRemnants:halfScaleForKT
0.50.5TimeShower:pTminChgQ
0.50.5TimeShower:pTmin
0.13650.1365TimeShower:alphaSvalue
0.13650.1365SpaceShower:alphaSvalue
0.130.13SigmaProcess:alphaSvalue
0.130.13MultipartonInteractions:alphaSvalue
1.801.80reconnectRange
1.61.85expPow
2.4023742.280pT0Ref
NNPDF2.3LONNPDF2.3LOPDF
MonashStarMonash
PYTHIA 8 Tunes: Peter Skands Tune Monash-NNPDF2.3LO and CMS Tune CUETP8M1-NNPDF2.3LO (MonashStar).
CMS Tune MonashStarpT0Ref = 2.402374ecmPow = 0.25208ecmRef = 7000
2.80813
2.4027
1.7431.96
1.4320.9
1.0860.3
pT0 (GeV/c)
Ecm(TeV)
Skands-MonashpT0Ref = 2.280ecmPow = 0.2150ecmRef = 7000
2.60513
2.2807
1.7341.96
1.4670.9
1.1580.3
pT0 (GeV/c)
Ecm(TeV)
Start with Monash and change 3 parameters!
from CMS
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 5
UE ObservablesUE Observables“Transverse” Charged Particle Density: Number of charged particles (pT > 0.5 GeV/c, |η| < ηcut) in the “transverse” region as defined by the leading charged particle, PTmax, divided by the area in η-φ space, 2ηcut×2π/3, averaged over all events with at least one particle with pT > 0.5 GeV/c, |η| < ηcut.
PTmax Direction
Δφ
“Toward”
“Transverse” “Transverse”
“Away”
“Transverse” Charged PTsum Density: Scalar pT sum of the charged particles (pT > 0.5 GeV/c, |η| < ηcut) in the “transverse”region as defined by the leading charged particle, PTmax, divided by the area in η-φ space, 2ηcut×2π/3, averaged over all events with at least one particle with pT > 0.5 GeV/c, |η| < ηcut. “Transverse” Charged Particle Average PT: Event-by-event <pT> = PTsum/Nchg for charged particles (pT > 0.5 GeV/c, |η| < ηcut) 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, |η| < ηcut.
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, |η| < ηcut. However, if there are no charged particles in the “transverse” region then the event is not used in constructing the “transverse”average pT.
ηcut = 0.8
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 6
UE ObservablesUE Observables“transMAX” and “transMIN” Charged Particle Density: Number of charged particles (pT > 0.5 GeV/c, |η| < 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 η-φ space, 2ηcut×2π/6, averaged over all events with at least one particle with pT> 0.5 GeV/c, |η| < ηcut.
PTmax Direction Δφ
“Toward”
“TransMAX” “TransMIN”
“Away”
“transMAX” and “transMIN” Charged PTsum Density: Scalar pTsum of charged particles (pT > 0.5 GeV/c, |η| < 0.8) in the themaximum (minimum) of the two “transverse” regions as defined by the leading charged particle, PTmax, divided by the area in η-φspace, 2ηcut×2π/6, averaged over all events with at least one particle with pT > 0.5 GeV/c, |η| < ηcut.
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
ηcut = 0.8Overall “Transverse” = “transMAX” + “transMIN”
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 7
““transMINtransMIN”” & & ““transDIFtransDIF””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
Δφ
“TransMAX” “TransMIN”
“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”
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 8
MB&UE Working Group
CMS
ATLAS
MB & UE Common Plots
The LPCC MB&UE Working Group has suggested several MB&UE “Common Plots” the all the LHC groups can produce and compare with each other.
Proton Proton
“Minimum Bias” Collisions
Proton Proton
PT(hard)
Outgoing Parton
Outgoing Parton
Underlying EventUnderlying Event
Initial-State Radiation
Final-StateRadiation
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 9
UE Common PlotsUE Common Plots
"Transverse" Charged PTsum Density: dPT/dηdφ
0.0
0.2
0.4
0.6
0.8
0 2 4 6 8 10 12 14
PTmax (GeV/c)
PTsu
m D
ensi
ty (G
eV/c
)
900 GeVCharged Particles (|η| < 0.8, PT > 0.5 GeV/c)
CMS (solid red)ATLAS (solid blue)ALICE (open black)
RDF Preliminary corrected data
"Transverse" Charged Particle Density: dN/dηdφ
0.0
0.2
0.4
0.6
0.8
0 2 4 6 8 10 12 14
PTmax (GeV/c)
"Tra
nsve
rse"
Cha
rged
Den
sity RDF Preliminary
corrected data
900 GeVCharged Particles (|η| < 0.8, PT > 0.5 GeV/c)
CMS (solid red)ATLAS (solid blue)ALICE (open black)
"Transverse" Charged PTsum Density: dPT/dηdφ
0.0
0.4
0.8
1.2
1.6
0 5 10 15 20 25 30
PTmax (GeV/c)
PTsu
m D
ensi
ty (G
eV/c
)
RDF Preliminary corrected data
7 TeV
Charged Particles (|η| < 0.8, PT > 0.5 GeV/c)
CMS (solid red)ATLAS (solid blue)ALICE (open black)
"Transverse" Charged Particle Density: dN/dηdφ
0.0
0.5
1.0
1.5
0 5 10 15 20 25 30
PTmax (GeV/c)
"Tra
nsve
rse"
Cha
rged
Den
sity
7 TeV
Charged Particles (|η| < 0.8, PT > 0.5 GeV/c)
CMS (solid red)ATLAS (solid blue)ALICE (open black)
RDF Preliminary corrected data
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 10
CDF versus CMSCDF versus CMS
CDF and LHC data at 900 GeV/c on the charged particle density in the “transverse”region as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and |η| < 0.8. The data are corrected to the particle level with errors that include both the statistical error and the systematic uncertainty.
CDF and LHC data at 900 GeV/c on the charged PTsum density in the “transverse”region as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and |η| < 0.8. The data are corrected to the particle level with errors that include both the statistical error and the systematic uncertainty.
"TransAVE" Charged Particle Density: dN/dηdφ
0.00
0.25
0.50
0.75
0 4 8 12 16 20
PTmax (GeV/c)
Cha
rged
Par
ticle
Den
sity
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
900 GeV
RDF Preliminary corrected data
CMS
CDF
ATLASALICE
"TransAVE" Charged PTsum Density: dPT/dηdφ
0.00
0.26
0.52
0.78
0 4 8 12 16 20
PTmax (GeV/c)
PTsu
m D
ensi
ty (G
eV/c
)
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
900 GeV
RDF Preliminary corrected data
CMS
CDF
ATLAS
ALICE
CDF versus LHCCDF versus LHC
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 11
CUETP8S1CUETP8S1--CTEQ6LCTEQ6L
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 |η| < 0.8. The data are compared with PYTHIA 8 Tune CUETP8S1-CTEQ6L (excludes 300 GeVin fit).
"TransAVE" Charged Particle Density
0.0
0.4
0.8
1.2
0 5 10 15 20 25 30
PTmax (GeV/c)
Cha
rged
Par
ticle
Den
sity
CMS Tune CUETP8S1-CTEQ6L
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
300 GeV
900 GeV
1.96 TeV
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 |η| < 0.8. The data are compared with PYTHIA 6.4 Tune Z2*.
"TransAVE" Charged Particle Density
0.0
0.4
0.8
1.2
0 5 10 15 20 25 30
PTmax (GeV/c)
Cha
rged
Par
ticle
Den
sity
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
300 GeV
900 GeV
1.96 TeV
7 TeVTune Z2*-CTEQ6L
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 12
CUETP8S1CUETP8S1--CTEQ6LCTEQ6L"TransAVE" Charged PTsum Density
0.0
0.5
1.0
1.5
0 5 10 15 20 25 30
PTmax (GeV/c)
Cha
rged
PTs
um D
ensi
ty (G
eV/c
)
CMS Tune CUETP8S1-CTEQ6L
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
300 GeV
900 GeV
1.96 TeV
7 TeV
"TransAVE" Charged PTsum Density
0.0
0.5
1.0
1.5
0 5 10 15 20 25 30
PTmax (GeV/c)
Cha
rged
PTs
um D
ensi
ty (G
eV/c
)
300 GeV
900 GeV
1.96 TeV
7 TeVTune Z2*-CTEQ6L
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
CMS data at 7 TeV and CDF data at 1.96 TeV, 900 GeV, and 300 GeV on the charged PTsumdensity in the “transAVE” region as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and |η| < 0.8. The data are compared with PYTHIA 6.4 Tune Z2*.
CMS data at 7 TeV and CDF data at 1.96 TeV, 900 GeV, and 300 GeV on the charged PTsumdensity in the “transAVE” region as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and |η| < 0.8. The data are compared with PYTHIA 8 Tune CUETP8S1-CTEQ6L (excludes 300 GeVin fit).
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 13
CUETP8M1CUETP8M1--NNPDF2.3LONNPDF2.3LO
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 |η| < 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 |η| < 0.8. The data are compared with the PYTHIA 8 Tune CUETP8M1-NNPDF2.3LO (excludes 300 GeV in fit).
"TransAVE" Charged Particle Density
0.0
0.4
0.8
1.2
0 5 10 15 20 25 30
PTmax (GeV/c)
Cha
rged
Par
ticle
Den
sity
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
300 GeV
900 GeV
1.96 TeV
7 TeVCUETP8M1-NNPDF2.3LO
"TransAVE" Charged Particle Density
0.0
0.4
0.8
1.2
0 5 10 15 20 25 30
PTmax (GeV/c)
Cha
rged
Par
ticle
Den
sity
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
300 GeV
900 GeV
1.96 TeV
7 TeVMonash-NNPDF2.3LO
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 14
Energy DependenceEnergy Dependence
CMS data at 7 TeV and CDF data at 1.96 TeV, 900 GeV, and 300 GeV on the charged PTsumdensity in the “transAVE” region as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and |η| < 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 PTsumdensity in the “transAVE” region as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and |η| < 0.8. The data are compared with the PYTHIA 8 Tune CUETP8M1-NNPDF2.3LO (excludes 300 GeV in fit).
"TransAVE" Charged PTsum Density
0.0
0.5
1.0
1.5
0 5 10 15 20 25 30
PTmax (GeV/c)
Cha
rged
PTs
um D
ensi
ty (G
eV/c
)
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
300 GeV
900 GeV
1.96 TeV
7 TeVMonash-NNPDF2.3LO
"TransAVE" Charged PTsum Density
0.0
0.5
1.0
1.5
0 5 10 15 20 25 30
PTmax (GeV/c)
Cha
rged
PTs
um D
ensi
ty (G
eV/c
)
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
300 GeV
900 GeV
1.96 TeV
7 TeVCUETP8M1-NNPDF2.3LO
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 15
Energy DependenceEnergy Dependence
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 |η| < 0.8.
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 |η| < 0.8 with 5 < PTmax < 6 GeV/c. The data are plotted versus the center-of-mass energy (log scale).
"TransAVE" Charged Particle Density
0.0
0.4
0.8
1.2
0 5 10 15 20 25 30
PTmax (GeV/c)
Cha
rged
Par
ticle
Den
sity
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
300 GeV
900 GeV
1.96 TeV
7 TeV
"TransAVE" Charged Particle Density: dN/dηdφ
0.2
0.6
1.0
1.4
0.1 1.0 10.0 100.0
Center-of-Mass Energy (GeV)
Cha
rged
Par
ticle
Den
sity
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
5.0 < PTmax < 6.0 GeV/c
CMS solid dotsCDF solid squares
13 TeV
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 16
Energy DependenceEnergy Dependence"TransAVE" Charged Particle Density: dN/dηdφ
0.2
0.6
1.0
1.4
0.1 1.0 10.0 100.0
Center-of-Mass Energy (GeV)
Cha
rged
Par
ticle
Den
sity
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
5.0 < PTmax < 6.0 GeV/c
CMS solid dotsCDF solid squares
Tune Z2*-CTEQ6L (solid line)
"TransAVE" Charged Particle Density: dN/dηdφ
0.2
0.6
1.0
1.4
0.1 1.0 10.0 100.0
Center-of-Mass Energy (GeV)
Cha
rged
Par
ticle
Den
sity
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
5.0 < PTmax < 6.0 GeV/c
CMS solid dotsCDF solid squares
CUETP8S1-CTEQ6L (solid line)
13 TeV
"TransAVE" Charged Particle Density: dN/dηdφ
0.2
0.6
1.0
1.4
0.1 1.0 10.0 100.0
Center-of-Mass Energy (GeV)
Cha
rged
Par
ticle
Den
sity
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
5.0 < PTmax < 6.0 GeV/c
CMS solid dotsCDF solid squares
Monash-NNPDF2.3LO (solid line)
"TransAVE" Charged Particle Density: dN/dηdφ
0.2
0.6
1.0
1.4
0.1 1.0 10.0 100.0
Center-of-Mass Energy (GeV)
Cha
rged
Par
ticle
Den
sity
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
5.0 < PTmax < 6.0 GeV/c
CMS solid dotsCDF solid squares
CUETP8M1-NNPDF2.3LO (solid line)
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 17
Energy DependenceEnergy Dependence"TransAVE" Charged Particle Density: dN/dηdφ
0.2
0.6
1.0
1.4
0.1 1.0 10.0 100.0
Center-of-Mass Energy (GeV)
Cha
rged
Par
ticle
Den
sity
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
5.0 < PTmax < 6.0 GeV/c
CMS solid dotsCDF solid squares
Tune Z2*-CTEQ6L (solid line)
"TransAVE" Charged Particle Density: dN/dηdφ
0.2
0.6
1.0
1.4
0.1 1.0 10.0 100.0
Center-of-Mass Energy (GeV)
Cha
rged
Par
ticle
Den
sity
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
5.0 < PTmax < 6.0 GeV/c
CMS solid dotsCDF solid squares
CUETP8S1-CTEQ6L (solid line)
13 TeV
"TransAVE" Charged Particle Density: dN/dηdφ
0.2
0.6
1.0
1.4
0.1 1.0 10.0 100.0
Center-of-Mass Energy (GeV)
Cha
rged
Par
ticle
Den
sity
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
5.0 < PTmax < 6.0 GeV/c
CMS solid dotsCDF solid squares
Monash-NNPDF2.3LO (solid line)
"TransAVE" Charged Particle Density: dN/dηdφ
0.2
0.6
1.0
1.4
0.1 1.0 10.0 100.0
Center-of-Mass Energy (GeV)
Cha
rged
Par
ticle
Den
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Charged Particles (|η|<0.8, PT>0.5 GeV/c)
5.0 < PTmax < 6.0 GeV/c
CMS solid dotsCDF solid squares
CUETP8M1-NNPDF2.3LO (solid line)
"TransAVE" Charged Particle Density: dN/dηdφ
0.2
0.6
1.0
1.4
0.1 1.0 10.0 100.0
Center-of-Mass Energy (GeV)
Cha
rged
Par
ticle
Den
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Charged Particles (|η|<0.8, PT>0.5 GeV/c)
5.0 < PTmax < 6.0 GeV/c
CMS solid dotsCDF solid squares
Tune Z2*-CTEQ6L (green line)CUETP8S1-CTEQ6L (black line)Monash-NNPDF2.3LO (red line)
CUETP8M1-NNPDF2.3LO (blue line) 13 TeV
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 18
Energy DependenceEnergy Dependence
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 |η| < 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 Particle Density: dN/dηdφ
0.2
0.6
1.0
1.4
0.1 1.0 10.0 100.0
Center-of-Mass Energy (GeV)
Cha
rged
Par
ticle
Den
sity
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
5.0 < PTmax < 6.0 GeV/c
CMS solid dotsCDF solid squares
Tune Z2*-CTEQ6L (green line)CUETP8S1-CTEQ6L (black line)Monash-NNPDF2.3LO (red line)
CUETP8M1-NNPDF2.3LO (blue line)
"TransAVE" Charged PTsum Density: dPT/dηdφ
0.2
0.6
1.0
1.4
0.1 1.0 10.0 100.0
Center-of-Mass Energy (GeV)
Cha
rged
PTs
um D
ensi
ty (G
eV/c
)
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
5.0 < PTmax < 6.0 GeV/c
CMS solid dotsCDF solid squares
Tune Z2*-CTEQ6L (green line)CUETP8S1-CTEQ6L (black line)Monash-NNPDF2.3LO (red line)
CUETP8M1-NNPDF2.3LO (blue line)
CMS and CDF data on the charged PTsumdensity in the “transAVE” region as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and |η| < 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.
13 TeV13 TeV
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 19
Predictions at 13 Predictions at 13 TeVTeV"TransMAX" Charged Particle Density
0.0
0.7
1.4
2.1
0 5 10 15 20 25 30
PTmax (GeV/c)
Ave
rage
Den
sity
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
13 TeV
Tune Z2*-CTEQ6L (green line)CUETP8S1-CTEQ6L (black line)Monash-NNPDF2.3LO (red line)
CUETP8M1-NNPDF2.3LO (blue line)
"TransMIN" Charged Particle Density
0.00
0.32
0.64
0.96
0 5 10 15 20 25 30
PTmax (GeV/c)
Ave
rage
Den
sity
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
13 TeV
Tune Z2*-CTEQ6L (green line)CUETP8S1-CTEQ6L (black line)Monash-NNPDF2.3LO (red line)
CUETP8M1-NNPDF2.3LO (blue line)
"TransMAX" Charged PTsum Density
0.0
1.0
2.0
3.0
0 5 10 15 20 25 30
PTmax (GeV/c)
Ave
rage
Den
sity
(GeV
/c)
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
13 TeV
Tune Z2*-CTEQ6L (green line)CUETP8S1-CTEQ6L (black line)Monash-NNPDF2.3LO (red line)
CUETP8M1-NNPDF2.3LO (blue line)
"TransMIN" Charged PTsum Density
0.0
0.3
0.6
0.9
0 5 10 15 20 25 30
PTmax (GeV/c)
Ave
rage
Den
sity
(GeV
/c)
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
13 TeV
Tune Z2*-CTEQ6L (green line)CUETP8S1-CTEQ6L (black line)Monash-NNPDF2.3LO (red line)
CUETP8M1-NNPDF2.3LO (blue line)
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 20
Predictions at 13 Predictions at 13 TeVTeV"TransAVE" Charged Particle Density
0.0
0.5
1.0
1.5
0 5 10 15 20 25 30
PTmax (GeV/c)
Ave
rage
Den
sity
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
13 TeV
Tune Z2*-CTEQ6L (green line)CUETP8S1-CTEQ6L (black line)Monash-NNPDF2.3LO (red line)
CUETP8M1-NNPDF2.3LO (blue line)
"TransDIF" Charged Particle Density
0.0
0.5
1.0
1.5
0 5 10 15 20 25 30
PTmax (GeV/c)
Ave
rage
Den
sity
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
13 TeV
Tune Z2*-CTEQ6L (green line)CUETP8S1-CTEQ6L (black line)Monash-NNPDF2.3LO (red line)
CUETP8M1-NNPDF2.3LO (blue line)
"TransAVE" Charged PTsum Density
0.0
0.7
1.4
2.1
0 5 10 15 20 25 30
PTmax (GeV/c)
Ave
rage
Den
sity
(GeV
/c)
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
13 TeV
Tune Z2*-CTEQ6L (green line)CUETP8S1-CTEQ6L (black line)Monash-NNPDF2.3LO (red line)
CUETP8M1-NNPDF2.3LO (blue line)
"TransDIF" Charged PTsum Density
0.0
0.7
1.4
2.1
0 5 10 15 20 25 30
PTmax (GeV/c)
Ave
rage
Den
sity
(GeV
/c)
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
13 TeV
Tune Z2*-CTEQ6L (green line)CUETP8S1-CTEQ6L (black line)Monash-NNPDF2.3LO (red line)
CUETP8M1-NNPDF2.3LO (blue line)
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 21
Predictions at 13 Predictions at 13 TeVTeV
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 |η| < 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 |η| < 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 Particle Density: dN/dηdφ
0.2
0.6
1.0
1.4
0.1 1.0 10.0 100.0
Center-of-Mass Energy (GeV)
Cha
rged
Par
ticle
Den
sity
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
5.0 < PTmax < 6.0 GeV/c
CMS solid dotsCDF solid squares
Tune Z2*-CTEQ6L (green line)CUETP8S1-CTEQ6L (black line)Monash-NNPDF2.3LO (red line)
CUETP8M1-NNPDF2.3LO (blue line)
"TransAVE" Charged Particle Density
0.0
0.5
1.0
1.5
0 5 10 15 20 25 30
PTmax (GeV/c)
Ave
rage
Den
sity
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
13 TeV
Tune Z2*-CTEQ6L (green line)CUETP8S1-CTEQ6L (black line)Monash-NNPDF2.3LO (red line)
CUETP8M1-NNPDF2.3LO (blue line)
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 22
Predictions at 13 Predictions at 13 TeVTeV
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 |η| < 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 PTsumdensity in the “transAVE” region as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and |η| < 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/dηdφ
0.2
0.6
1.0
1.4
0.1 1.0 10.0 100.0
Center-of-Mass Energy (GeV)
Cha
rged
PTs
um D
ensi
ty (G
eV/c
)
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
5.0 < PTmax < 6.0 GeV/c
CMS solid dotsCDF solid squares
Tune Z2*-CTEQ6L (green line)CUETP8S1-CTEQ6L (black line)Monash-NNPDF2.3LO (red line)
CUETP8M1-NNPDF2.3LO (blue line)
"TransAVE" Charged PTsum Density
0.0
0.7
1.4
2.1
0 5 10 15 20 25 30
PTmax (GeV/c)
Ave
rage
Den
sity
(GeV
/c)
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
13 TeV
Tune Z2*-CTEQ6L (green line)CUETP8S1-CTEQ6L (black line)Monash-NNPDF2.3LO (red line)
CUETP8M1-NNPDF2.3LO (blue line)
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 23
Predictions at 13 Predictions at 13 TeVTeV
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 |η| < 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 PTsumdensity in the “transAVE” region as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and |η| < 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/dηdφ
0.2
0.6
1.0
1.4
0.1 1.0 10.0 100.0
Center-of-Mass Energy (GeV)
Cha
rged
PTs
um D
ensi
ty (G
eV/c
)
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
5.0 < PTmax < 6.0 GeV/c
CMS solid dotsCDF solid squares
Tune Z2*-CTEQ6L (green line)CUETP8S1-CTEQ6L (black line)Monash-NNPDF2.3LO (red line)
CUETP8M1-NNPDF2.3LO (blue line)
"TransAVE" Charged PTsum Density
0.0
0.7
1.4
2.1
0 5 10 15 20 25 30
PTmax (GeV/c)
Ave
rage
Den
sity
(GeV
/c)
Charged Particles (|η|<0.8, PT>0.5 GeV/c)
13 TeV
Tune Z2*-CTEQ6L (green line)CUETP8S1-CTEQ6L (black line)Monash-NNPDF2.3LO (red line)
CUETP8M1-NNPDF2.3LO (blue line)
I believe we knowwhat the UE will look
like at 13 TeV!
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 24
Charged Particle DensityCharged Particle Density
The charged particle density, dN/dη, for charged particles with pT > 40 MeV/c at 7 TeV predicted by the Monash tune for the non-diffractive component (ND) and the inelastic component (IN = ND+SD+DD).
The ratio on the inelastic component (IN = ND+SD+DD) and the non-diffractive component (ND) for the charged particle density, dN/dη, for charged particles with pT > 40 MeV/c as predicted by the Monash tune at 7 TeV.
Charged Particle Density: dN/dη
0
2
4
6
8
-8.0 -6.0 -4.0 -2.0 0.0 2.0 4.0 6.0 8.0
Pseudo-Rapidity η
Cha
rged
Par
ticle
Den
sity
Charged Particles (PT>40 MeV/c)
7 TeVMonash Tune
IN = ND + SD + DD
ND
Charged Particle Density: dN/dη
0.7
0.8
0.9
1.0
-8.0 -6.0 -4.0 -2.0 0.0 2.0 4.0 6.0 8.0
Pseudo-Rapidity η
Rat
io: I
N/N
D
Charged Particles (PT>40 MeV/c)
7 TeVMonash Tune
(ND+SD+DD)/ND
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 25
Charged Particle DensityCharged Particle Density
The charged particle density, dN/dη, for charged particles with pT > 40 MeV/c at 7 TeV predicted by the Monash tune for the non-diffractive component (ND) and the inelastic component (IN = ND+SD+DD).
The ratio on the inelastic component (IN = ND+SD+DD) and the non-diffractive component (ND) for the charged particle density, dN/dη, for charged particles with pT > 40 MeV/c as predicted by the Monash tune at 7 TeV.
Charged Particle Density: dN/dη
0
2
4
6
8
-8.0 -6.0 -4.0 -2.0 0.0 2.0 4.0 6.0 8.0
Pseudo-Rapidity η
Cha
rged
Par
ticle
Den
sity
Charged Particles (PT>40 MeV/c)
7 TeVMonash Tune
IN = ND + SD + DD
ND
Charged Particle Density: dN/dη
0.7
0.8
0.9
1.0
-8.0 -6.0 -4.0 -2.0 0.0 2.0 4.0 6.0 8.0
Pseudo-Rapidity η
Rat
io: I
N/N
D
Charged Particles (PT>40 MeV/c)
7 TeVMonash Tune
(ND+SD+DD)/NDAdding SD+DD reduces the ND contribution by ≈ 22%!
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 26
Charged Particle DensityCharged Particle Density
The charged particle density, dN/dη, for charged particles with pT > 40 MeV/c at 7 TeVpredicted by the Monash tune and the CMS tune CMS tune CUETP8S1-CTEQ6L for the inelastic component (IN = ND+SD+DD).
The charged particle difference, ΔNchg, for charged particles with pT > 40 MeV/c at 7 TeVbetween the Monash tune and the CMS tune CMS tune CUETP8S1-CTEQ6L for the inelastic component (IN = ND+SD+DD), where ΔNchg = Nchg(Monash)-Nchg(CMS1) and corresponds to the number of charged particles in 0.5 η.
Charged Particle Density: dN/dη
0
2
4
6
-8.0 -6.0 -4.0 -2.0 0.0 2.0 4.0 6.0 8.0
Pseudo-Rapidity η
Cha
rged
Par
ticle
Den
sity
Charged Particles (PT>40 MeV/c)
7 TeV
CMS1
Monash
IN = ND+SD+DD
Nchg Difference: Nchg(Monash)-Nchg(tune)
0.00
0.10
0.20
0.30
0.40
-8.0 -6.0 -4.0 -2.0 0.0 2.0 4.0 6.0 8.0
Pseudo-Rapidity η
ΔN
chg
in 0
.5 η
7 TeVIN = ND+SD+DD
ΔNchg in 0.5 η
CMS1
Charged Particles (PT>40 MeV/c)
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 27
Charged Particle DensityCharged Particle Density
The charged particle density, dN/dη, for charged particles with pT > 40 MeV/c at 7 TeVpredicted by the Monash-NNPDF2.3LO tune, the tune CUETP8S1-CTEQ6L (CMS1), and tune CUEP8M1-NNPDF2.3LO (Mstar) for the inelastic component (IN = ND+SD+DD).
Shows the charged particle difference, ΔNchg, for charged particles with pT > 40 MeV/c at 7 TeV between the Monash-NNPDF2.3LO tune and tune CUETP8S1-CTEQ6L (CMS1), and tune CUEP8M1-NNPDF2.3LO (Mstar) for the inelastic component (IN = ND+SD+DD), where ΔNchg = Nchg(Monash)-Nchg(tune) and corresponds to the number of charged particles in 0.5 η.
Charged Particle Density: dN/dη
2
3
4
5
6
-8.0 -6.0 -4.0 -2.0 0.0 2.0 4.0 6.0 8.0
Pseudo-Rapidity η
Cha
rged
Par
ticle
Den
sity
Charged Particles (PT>40 MeV/c)
7 TeVCMS1
Monash
IN = ND+SD+DD
Mstar
Nchg Difference: Nchg(Monash)-Nchg(tune)
0.00
0.10
0.20
0.30
0.40
-8.0 -6.0 -4.0 -2.0 0.0 2.0 4.0 6.0 8.0
Pseudo-Rapidity η
ΔN
chg
in 0
.5 η
7 TeVIN = ND+SD+DD
ΔNchg in 0.5 η
CMS1
Charged Particles (PT>40 MeV/c)
Mstar
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 28
Energy Flow: Energy Flow: dEdE/d/dηη
The energy density, dE/dη, at 7 TeV predicted by the Monash tune for the non-diffractive component (ND) and the inelastic component (IN = ND+SD+DD).
The ratio on the inelastic component (IN = ND+SD+DD) and the non-diffractive component (ND) energy density, dE/dη, predicted by the Monash tune at 7 TeV.
Energy Density: dE/dη
1
10
100
1000
-8.0 -6.0 -4.0 -2.0 0.0 2.0 4.0 6.0 8.0
Pseudo-Rapidity η
Ener
gy D
ensi
ty (G
eV)
7 TeVMonash Tune
IN = ND + SD + DD
ND
Energy Density: dE/dη
0.7
0.8
0.9
1.0
-8.0 -6.0 -4.0 -2.0 0.0 2.0 4.0 6.0 8.0
Pseudo-Rapidity η
Rat
io: I
N/N
D
7 TeVMonash Tune
(ND+SD+DD)/ND
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 29
Energy Flow: Energy Flow: dEdE/d/dηη
The energy density, dE/dη, at 7 TeV predicted by the Monash tune for the non-diffractive component (ND) and the inelastic component (IN = ND+SD+DD).
The ratio on the inelastic component (IN = ND+SD+DD) and the non-diffractive component (ND) energy density, dE/dη, predicted by the Monash tune at 7 TeV.
Energy Density: dE/dη
1
10
100
1000
-8.0 -6.0 -4.0 -2.0 0.0 2.0 4.0 6.0 8.0
Pseudo-Rapidity η
Ener
gy D
ensi
ty (G
eV)
7 TeVMonash Tune
IN = ND + SD + DD
ND
Energy Density: dE/dη
0.7
0.8
0.9
1.0
-8.0 -6.0 -4.0 -2.0 0.0 2.0 4.0 6.0 8.0
Pseudo-Rapidity η
Rat
io: I
N/N
D
7 TeVMonash Tune
(ND+SD+DD)/NDAdding SD+DD reduces the ND contribution by ≈ 23%!
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 30
Energy Flow: Energy Flow: dEdE/d/dηηEnergy Density: dE/dη
1
10
100
1000
-8.0 -6.0 -4.0 -2.0 0.0 2.0 4.0 6.0 8.0
Pseudo-Rapidity η
Ener
gy D
ensi
ty (G
eV)
7 TeV
CMS1
Monash
IN = ND+SD+DD
Energy Difference: E(Monash)-E(tune)
-20
0
20
40
60
-8.0 -6.0 -4.0 -2.0 0.0 2.0 4.0 6.0 8.0
Pseudo-Rapidity η
ΔE
(GeV
) in
0.5
η
7 TeVIN = ND+SD+DD
ΔE (GeV) in 0.5 η
CMS1
ForwardRegion
The energy density, dE/dη, at 7 TeV predicted by the Monash-NNPDF2.3LO tune and the tune CUETP8S1-CTEQ6L (CMS1) for the inelastic component (IN = ND+SD+DD).
The energy difference, ΔE, at 7 TeV between the Monash-NNPDF2.3LO and tune CUETP8S1-CTEQ6L (CMS1) for the inelastic component (IN = ND+SD+DD), where ΔE = E(Monash)-E(CMS1) and corresponds to the amount of energy in GeV in 0.5 η.
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 31
Energy Flow: Energy Flow: dEdE/d/dηη
Shows the energy density difference, ΔE, at 7 TeV between the Monash-NNPDF2.3LO tune, and tune CUETP8S1-CTEQ6L (CMS1), and tune CUEP8M1-NNPDF2.3LO (Mstar) for the inelastic component (IN = ND+SD+DD), where ΔE = E(Monash)-E(tune) and corresponds to the amount of energy in GeV in 0.5 η.
Energy Difference: E(Monash)-E(tune)
-20
0
20
40
60
-8.0 -6.0 -4.0 -2.0 0.0 2.0 4.0 6.0 8.0
Pseudo-Rapidity η
ΔE
(GeV
) in
0.5
η
7 TeVIN = ND+SD+DD
ΔE (GeV) in 0.5 ηCMS1
Mstar
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 32
Tuning the PDF!Tuning the PDF!
x0
slope
Start with the HERALOPDF functions, f(x). Modify the gluon distribution at small x by adding a function f1(x,p1,p2) with 2 parameters (p1 = x0, p2 = slope).
x0
New ApproachTune the PDF
Started with the SkandsMonash-NNPDF2.3LO tune!
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 33
TOTEM Forward TOTEM Forward dNdN/d/dηη
Use the CMS Tune CUETP8S1-HERALOPDF and vary the low x gluon distribution to try to improve the fit to the forward region (TOTEM data). Need to increase the gluon distribution at x < ≈ 10-5!
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 34
TOTEM Forward TOTEM Forward dNdN/d/dηηCan improve agreement
with TOTEM!
MPI contributes a lot to both central and forward dN/dη!
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 35
TOTEM Forward TOTEM Forward dNdN/d/dηη
Use the CMS Tune CUETP8S1-HERALOPDF and vary the low x gluon distribution to try to improve the fit to the forward region (TOTEM data).
Can improve agreement with TOTEM! Does not affect the central region.
However, changing thegluon distribution at low x
destroys the fit to the UE data!If you change the PDF, youmust change the UE tune
accordingly!
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 36
ReRe--Tune the UE ParametersTune the UE Parameters
Starting with the tunes that fit to the forward region (TOTEM data) re-tune the UE parameters of CMS Tune CUETP8S1-HERALOPDF to fit the UE data.
Need to start with a slightly different low x gluon distribution or do a simultaneous fit that varies both the low x gluon distribution and the UE parameters in an attempt to fit the central and forward dN/dη and the UE data.
Oops! Now agrees in the central region and is low
in the forward region.
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 37
Try AgainTry Again
Starting with a different low x gluon distribution re-tune the UE parameters of CMS Tune CUETP8S1-HERALOPDF to fit the UE data.
Perhaps we should do a simultaneous fit that varies both the low x gluon distribution and the UE parameters in an attempt to fit the central and forward dN/dη and the UE data.
Not bad! Now fits the forward region and the UE data. A little low in
the central region.
Before UE tuning After UE tuning
MPI@LHC 2014 Krakow, November 3, 2014
Rick Field – Florida/CDF/CMS Page 38
Try AgainTry Again
Starting with a different low x gluon distribution re-tune the UE parameters of CMS Tune CUETP8S1-HERALOPDF to fit the UE data.
Perhaps we should do a simultaneous fit that varies both the low x gluon distribution and the UE parameters in an attempt to fit the central and forward dN/dη and the UE data.
Not bad! Now fits the forward region and the UE data. A little low in
the central region.
Before UE tuning After UE tuning
Stay tuned! More CMS tunes coming!