QCD@LHC 2012 MSU, August 23, 2012 Rick Field – Florida/CDF/CMS Page 1 Rick Field University of Florida Outline of Talk Proton A ntiProton PT(hard) O utgoing Parton O utgoing Parton U nderlying Event U nderlying Event Initial-State R adiation Final-State Radiation CMS at the LHC CDF Run 2 CDF PYTHIA 6.2 Tevatron Tune A and Tune DW. CMS PYTHIA 6.4 LHC Tune Z1. 300 GeV, 900 GeV, 1.96 TeV 900 GeV, 7 & 8 TeV New UE data at 300 GeV, 900 GeV, and 1.96 TeV from the Tevatron Energy-Scan. New comparisons with PYTHIA 6.4 Tune Z1. Much more coming soon! MSU August 20-23, 2012 LPCC MB&UE working group “common plots”. Energy Dependence of the UE QCD@LHC 2012 QCD@LHC 2012
QCD@LHC 2012. Energy Dependence of the UE. Rick Field University of Florida. Outline of Talk. CDF PYTHIA 6.2 Tevatron Tune A and Tune DW. MSU August 20-23, 2012. CMS PYTHIA 6.4 LHC Tune Z1. LPCC MB&UE working group “common plots”. CDF Run 2. 300 GeV, 900 GeV, 1.96 TeV. - PowerPoint PPT Presentation
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QCD@LHC 2012 MSU, August 23, 2012
Rick Field – Florida/CDF/CMS Page 1
Rick FieldUniversity of Florida
Outline of Talk
Proton AntiProton
PT(hard)
Outgoing Parton
Outgoing Parton
Underlying Event Underlying Event
Initial-State Radiation
Final-State Radiation
CMS at the LHC
CDF Run 2
CDF PYTHIA 6.2 Tevatron Tune A and Tune DW.
CMS PYTHIA 6.4 LHC Tune Z1.
300 GeV, 900 GeV, 1.96 TeV
900 GeV, 7 & 8 TeV
New UE data at 300 GeV, 900 GeV, and 1.96 TeV from the Tevatron Energy-Scan.
New comparisons with PYTHIA 6.4 Tune Z1.
Much more coming soon!
MSU August 20-23, 2012
LPCC MB&UE working group “common plots”.
Energy Dependence of the UEQCD@LHC 2012QCD@LHC 2012
Start with the perturbative 2-to-2 (or sometimes 2-to-3) parton-parton scattering and add initial and final-state gluon radiation (in the leading log approximation or modified leading log approximation).
Hard Scattering
PT(hard)
Outgoing Parton
Outgoing Parton
Initial-State Radiation
Final-State Radiation
Hard Scattering
PT(hard)
Outgoing Parton
Outgoing Parton
Initial-State Radiation
Final-State Radiation
Proton AntiProton
Underlying Event Underlying Event
Proton AntiProton
Underlying Event Underlying Event
“Hard Scattering” Component
“Jet”
“Jet”
“Underlying Event”
The “underlying event” consists of the “beam-beam remnants” and from particles arising from soft or semi-soft multiple parton interactions (MPI).
Of course the outgoing colored partons fragment into hadron “jet” and inevitably “underlying event” observables receive contributions from initial and final-state radiation.
“Jet”
The “underlying event” is an unavoidable background to most collider observables and having good understand of it leads to
more precise collider measurements!
QCD@LHC 2012 MSU, August 23, 2012
Rick Field – Florida/CDF/CMS Page 3
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.
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
“Transverse” “Transverse”
“Toward”
“Away”
“Toward-Side” Jet
“Away-Side” Jet
“Transverse” region very sensitive to the “underlying event”!
CDF Run 1 Analysis
QCD@LHC 2012 MSU, August 23, 2012
Rick Field – Florida/CDF/CMS Page 4
““Transverse” Charged DensityTransverse” Charged Density
PTmax Direction
“Toward”
“Transverse” “Transverse”
“Away”
ChgJet#1 Direction
“Toward”
“Transverse” “Transverse”
“Away”
Shows the charged particle density in the “transverse” region for charged particles (pT > 0.5 GeV/c, || < 1) at 7 TeV as defined by PTmax, PT(chgjet#1), and PT(muon-pair) from PYTHIA Tune DW at the particle level (i.e. generator level). Charged particle jets are constructed using the Anti-KT algorithm with d = 0.5.
"Transverse" Charged Particle Density: dN/dd
0.0
0.4
0.8
1.2
1.6
0 5 10 15 20 25 30 35 40 45 50
PT(chgjet#1) or PTmax or PT(pair) (GeV/c)
"Tra
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har
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sity
7 TeV
Charged Particles (||<1.0, PT>0.5 GeV/c)
RDF Preliminarypy Tune DW generator level
PTmax
ChgJet#1
DY(muon-pair)70 < M(pair) < 110 GeV
Muon-Pair Direction
“Toward”
“Transverse” “Transverse”
“Away”
QCD@LHC 2012 MSU, August 23, 2012
Rick Field – Florida/CDF/CMS Page 5
Jet Radius DependenceJet Radius Dependence
The charged particle density in the “transverse” region as defined by the leading charged particle jet from PYTHIA Tune Z1. The charged particles are in the region pT > 0.5 GeV/c and || < 2.5. Charged particle jets are constructed using the Anti-KT algorithm with d = 0.2, 0.5, and 1.0 from charged particles in the region pT > 0.5 GeV/c and || < 2.5, however, the leading charged particle jet is required to have |(chgjet#1)| < 1.5.
The UE activity is higherfor large jet radius!
"Transverse" Charged Particle Density: dN/dd
0.0
0.5
1.0
1.5
0 10 20 30 40 50 60 70 80 90 100
PT(chgjet#1) GeV/c
Ch
arg
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Par
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Charged Particles (||<2.5, PT>0.5 GeV/c)
Chgjet#1 (||<1.5)
7 TeV
RDF PreliminarypyZ1 generator level
d = 0.5
d = 0.2
d = 1.0
Tune Z1
It seems that large jet radius “biases” the UE to be more active!
QCD@LHC 2012 MSU, August 23, 2012
Rick Field – Florida/CDF/CMS Page 6
Parameter Default
Description
PARP(83) 0.5 Double-Gaussian: Fraction of total hadronic matter within PARP(84)
PARP(84) 0.2 Double-Gaussian: Fraction of the overall hadron radius containing the fraction PARP(83) of the total hadronic matter.
PARP(85) 0.33 Probability that the MPI produces two gluons with color connections to the “nearest neighbors.
PARP(86) 0.66 Probability that the MPI produces two gluons either as described by PARP(85) or as a closed gluon loop. The remaining fraction consists of quark-antiquark pairs.
PARP(89) 1 TeV Determines the reference energy E0.
PARP(82) 1.9 GeV/c
The cut-off PT0 that regulates the 2-to-2 scattering divergence 1/PT4→1/(PT2+PT0
2)2
PARP(90) 0.16 Determines the energy dependence of the cut-off
PT0 as follows PT0(Ecm) = PT0(Ecm/E0) with = PARP(90)
PARP(67) 1.0 A scale factor that determines the maximum parton virtuality for space-like showers. The larger the value of PARP(67) the more initial-state radiation.
Hard Core
Multiple Parton Interaction
Color String
Color String
Multiple Parton Interaction
Color String
Hard-Scattering Cut-Off PT0
1
2
3
4
5
100 1,000 10,000 100,000
CM Energy W (GeV)P
T0
(G
eV
/c)
PYTHIA 6.206
= 0.16 (default)
= 0.25 (Set A))
Take E0 = 1.8 TeV
Reference pointat 1.8 TeV
Determine by comparingwith 630 GeV data!
Tuning PYTHIA 6.2:Tuning PYTHIA 6.2:Multiple Parton Interaction ParametersMultiple Parton Interaction Parameters
Determines the energy dependence of the MPI!
QCD@LHC 2012 MSU, August 23, 2012
Rick Field – Florida/CDF/CMS Page 7
Old PYTHIA default(more initial-state radiation)New PYTHIA default
(less initial-state radiation)
Parameter Tune B Tune A
MSTP(81) 1 1
MSTP(82) 4 4
PARP(82) 1.9 GeV 2.0 GeV
PARP(83) 0.5 0.5
PARP(84) 0.4 0.4
PARP(85) 1.0 0.9
PARP(86) 1.0 0.95
PARP(89) 1.8 TeV 1.8 TeV
PARP(90) 0.25 0.25
PARP(67) 1.0 4.0
Old PYTHIA default(more initial-state radiation)New PYTHIA default
(less initial-state radiation)
Plot shows the “transverse” charged particle density versus PT(chgjet#1) compared to the QCD hard scattering predictions of two tuned versions of PYTHIA 6.206 (CTEQ5L, Set B (PARP(67)=1) and Set A (PARP(67)=4)).
Shows the “transverse” charged PTsum density (||<1, PT>0.4 GeV) versus PT(charged jet#1) at 630 GeV predicted by HERWIG 6.4 (PT(hard) > 3 GeV/c, CTEQ5L) and a tuned version of PYTHIA 6.206 (PT(hard) > 0, CTEQ5L, Set A, = 0, = 0.16 (default) and = 0.25 (preferred)).
Also shown are the PTsum densities (0.16 GeV/c and 0.54 GeV/c) determined from the Tano, Kovacs, Huston, and Bhatti “transverse” cone analysis at 630 GeV.
Increasing produces less energy dependence for the UE resulting in
less UE activity at the LHC!
Reference pointE0 = 1.8 TeV
Rick Field Fermilab MC WorkshopOctober 4, 2002!
QCD@LHC 2012 MSU, August 23, 2012
Rick Field – Florida/CDF/CMS Page 9
Min-Bias “Associated”Min-Bias “Associated”Charged Particle DensityCharged Particle Density
Shows the “associated” charged particle density in the “transverse” region as a function of PTmax for charged particles (pT > 0.5 GeV/c, || < 1, not including PTmax) for “min-bias” events at 0.2 TeV, 0.9 TeV, 1.96 TeV, 7 TeV, 10 TeV, 14 TeV predicted by PYTHIA Tune DW at the particle level (i.e. generator level).
PTmax Direction
“Toward”
“Transverse” “Transverse”
“Away”
PTmax Direction
“Toward”
“Transverse” “Transverse”
“Away”
RHIC Tevatron
0.2 TeV → 1.96 TeV (UE increase ~2.7 times)
PTmax Direction
“Toward”
“Transverse” “Transverse”
“Away”
LHC
1.96 TeV → 14 TeV (UE increase ~1.9 times)
Linear scale!
"Transverse" Charged Particle Density: dN/dd
0.0
0.4
0.8
1.2
0 5 10 15 20 25
PTmax (GeV/c)
"Tra
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Ch
arg
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Charged Particles (||<1.0, PT>0.5 GeV/c)
RDF Preliminarypy Tune DW generator level
Min-Bias 14 TeV
1.96 TeV
0.2 TeV
7 TeV
0.9 TeV
10 TeV
"Transverse" Charged Particle Density: dN/dd
0.0
0.4
0.8
1.2
0 2 4 6 8 10 12 14
Center-of-Mass Energy (TeV)
"Tra
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arg
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ensi
ty RDF Preliminarypy Tune DW generator level
Charged Particles (||<1.0, PT>0.5 GeV/c)
PTmax = 5.25 GeV/c
RHIC
Tevatron900 GeV
LHC7
LHC14
LHC10
QCD@LHC 2012 MSU, August 23, 2012
Rick Field – Florida/CDF/CMS Page 10
Min-Bias “Associated”Min-Bias “Associated”Charged Particle DensityCharged Particle Density
Shows the “associated” charged particle density in the “transverse” region as a function of PTmax for charged particles (pT > 0.5 GeV/c, || < 1, not including PTmax) for “min-bias” events at 0.2 TeV, 0.9 TeV, 1.96 TeV, 7 TeV, 10 TeV, 14 TeV predicted by PYTHIA Tune DW at the particle level (i.e. generator level).
Log scale!
"Transverse" Charged Particle Density: dN/dd
0.0
0.4
0.8
1.2
0 5 10 15 20 25
PTmax (GeV/c)
"Tra
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Ch
arg
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en
sity
Charged Particles (||<1.0, PT>0.5 GeV/c)
RDF Preliminarypy Tune DW generator level
Min-Bias 14 TeV
1.96 TeV
0.2 TeV
7 TeV
0.9 TeV
10 TeV
"Transverse" Charged Particle Density: dN/dd
0.0
0.4
0.8
1.2
0.1 1.0 10.0 100.0
Center-of-Mass Energy (TeV)
"Tra
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Ch
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ensi
ty RDF Preliminarypy Tune DW generator level
Charged Particles (||<1.0, PT>0.5 GeV/c)
PTmax = 5.25 GeV/c
RHIC
Tevatron
900 GeV
LHC7
LHC14LHC10
PTmax Direction
“Toward”
“Transverse” “Transverse”
“Away”
PTmax Direction
“Toward”
“Transverse” “Transverse”
“Away”
LHC7 LHC14
7 TeV → 14 TeV (UE increase ~20%)
Linear on a log plot!
QCD@LHC 2012 MSU, August 23, 2012
Rick Field – Florida/CDF/CMS Page 11
PYTHIA Tune DWPYTHIA Tune DW
PTmax Direction
“Toward”
“Transverse” “Transverse”
“Away”
"Transverse" Charged Particle Density: dN/dd
0.0
0.4
0.8
1.2
0 2 4 6 8 10 12 14 16 18 20
PTmax (GeV/c)
"Tra
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erse
" C
har
ged
Den
sity RDF Preliminary
ATLAS corrected dataTune DW generator level
900 GeV
7 TeV
Charged Particles (||<2.5, PT>0.5 GeV/c)
ATLAS preliminary data at 900 GeV and 7 TeV on the “transverse” charged particle density, dN/dd, as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 2.5. The data are corrected and compared with PYTHIA Tune DW at the generator level.
CMS preliminary data at 900 GeV and 7 TeV on the “transverse” charged particle density, dN/dd, as defined by the leading charged particle jet (chgjet#1) for charged particles with pT > 0.5 GeV/c and || < 2. The data are uncorrected and compared with PYTHIA Tune DW after detector simulation.
"Transverse" Charged Particle Density: dN/dd
0.0
0.4
0.8
1.2
0 5 10 15 20 25 30 35 40 45 50
PT(chgjet#1) GeV/c
Ch
arg
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arti
cle
Den
sity
900 GeV
CMS Preliminarydata uncorrected
pyDW + SIM
Charged Particles (||<2.0, PT>0.5 GeV/c)
7 TeV
CMS ATLAS
PT(chgjet#1) Direction
“Toward”
“Transverse” “Transverse”
“Away”
"Transverse" Charged Particle Density: dN/dd
0.0
0.4
0.8
1.2
0 50 100 150 200 250 300 350 400
PT(jet#1) GeV/c
Ch
arg
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arti
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Den
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CDF 1.96 TeVLeading Jet
RDF Preliminarydata corrected
pyDW generator level
Charged Particles (PT>0.5 GeV/c, || < 1.0)
QCD@LHC 2012 MSU, August 23, 2012
Rick Field – Florida/CDF/CMS Page 12
PYTHIA Tune DWPYTHIA Tune DW
Ratio of CMS preliminary data at 900 GeV and 7 TeV on the “transverse” charged particle density, dN/dd, as defined by the leading charged particle jet (chgjet#1) for charged particles with pT > 0.5 GeV/c and || < 2. The data are uncorrected and compared with PYTHIA Tune DW after detector simulation.
"Transverse" Charged Particle Density: dN/dd
0.0
1.0
2.0
3.0
0 2 4 6 8 10 12 14 16 18
PT(chgjet#1) (GeV/c)
Rat
io:
7 T
eV/9
00 G
eV
CMS Preliminarydata uncorrected
pyDW + SIM
Charged Particles (||<2.0, PT>0.5 GeV/c) 7 TeV / 900 GeV
CMS
PT(chgjet#1) Direction
“Toward”
“Transverse” “Transverse”
“Away”
CMS preliminary data at 900 GeV and 7 TeV on the “transverse” charged particle density, dN/dd, as defined by the leading charged particle jet (chgjet#1) for charged particles with pT > 0.5 GeV/c and || < 2. The data are uncorrected and compared with PYTHIA Tune DW after detector simulation.
"Transverse" Charged Particle Density: dN/dd
0.0
0.4
0.8
1.2
0 5 10 15 20 25 30 35 40 45 50
PT(chgjet#1) GeV/c
Ch
arg
ed P
arti
cle
Den
sity
900 GeV
CMS Preliminarydata uncorrected
pyDW + SIM
Charged Particles (||<2.0, PT>0.5 GeV/c)
7 TeV
CMS
PT(chgjet#1) Direction
“Toward”
“Transverse” “Transverse”
“Away”
Ratio
QCD@LHC 2012 MSU, August 23, 2012
Rick Field – Florida/CDF/CMS Page 13
PYTHIA Tune Z1PYTHIA Tune Z1
Proton Proton
PT(hard)
Outgoing Parton
Outgoing Parton
Underlying Event Underlying Event
Initial-State Radiation
Final-State Radiation
I believe that it is time to move to PYTHIA 6.4 (pT-ordered parton showers and new MPI model)!
Tune Z1: I started with the parameters of ATLAS Tune AMBT1, but I changed LO* to CTEQ5L and I varied PARP(82) and PARP(90) to get a very good fit of the CMS UE data at 900 GeV and 7 TeV.
UE&MB@CMSUE&MB@CMS
All my previous tunes (A, DW, DWT, D6, D6T, CW, X1, and X2) were PYTHIA 6.4 tunes using the old Q2-ordered parton showers and the old MPI model (really 6.2 tunes)!
PARP(90)
Color
Connections
PARP(82)
Diffraction
The ATLAS Tune AMBT1 was designed to fit the inelastic data for Nchg ≥ 6 and to fit the PTmax UE data with PTmax > 10 GeV/c. Tune AMBT1 is primarily a min-bias tune, while Tune Z1 is a UE tune!
QCD@LHC 2012 MSU, August 23, 2012
Rick Field – Florida/CDF/CMS Page 14
PYTHIA Tune Z1PYTHIA Tune Z1Parameter
Tune Z1
(R. Field CMS)Tune AMBT1
(ATLAS)
Parton Distribution Function CTEQ5L LO*
PARP(82) – MPI Cut-off 1.932 2.292
PARP(89) – Reference energy, E0 1800.0 1800.0
PARP(90) – MPI Energy Extrapolation 0.275 0.25
PARP(77) – CR Suppression 1.016 1.016
PARP(78) – CR Strength 0.538 0.538
PARP(80) – Probability colored parton from BBR 0.1 0.1
PARP(83) – Matter fraction in core 0.356 0.356
PARP(84) – Core of matter overlap 0.651 0.651
PARP(62) – ISR Cut-off 1.025 1.025
PARP(93) – primordial kT-max 10.0 10.0
MSTP(81) – MPI, ISR, FSR, BBR model 21 21
MSTP(82) – Double gaussion matter distribution 4 4
MSTP(91) – Gaussian primordial kT 1 1
MSTP(95) – strategy for color reconnection 6 6
Parameters not shown are the PYTHIA 6.4
defaults!
QCD@LHC 2012 MSU, August 23, 2012
Rick Field – Florida/CDF/CMS Page 15
CMS UE DataCMS UE Data
CMS preliminary data at 900 GeV and 7 TeV on the “transverse” charged PTsum density, dPT/dd, as defined by the leading charged particle jet (chgjet#1) for charged particles with pT > 0.5 GeV/c and || < 2.0. The data are corrected and compared with PYTHIA Tune Z1 at the generator level.
CMS preliminary data at 900 GeV and 7 TeV on the “transverse” charged particle density, dN/dd, as defined by the leading charged particle jet (chgjet#1) for charged particles with pT > 0.5 GeV/c and || < 2.0. The data are corrected and compared with PYTHIA Tune Z1 at the generator level.
CMS
"Transverse" Charged Particle Density: dN/dd
0.0
0.4
0.8
1.2
1.6
0 10 20 30 40 50 60 70 80 90 100
PT(chgjet#1) GeV/c
Ch
arg
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Par
ticl
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CMS Preliminarydata corrected
Tune Z1 generator level
900 GeV
7 TeV
Charged Particles (||<2.0, PT>0.5 GeV/c)
"Transverse" Charged PTsum Density: dPT/dd
0.0
0.4
0.8
1.2
1.6
2.0
0 10 20 30 40 50 60 70 80 90 100
PT(chgjet#1) GeV/c
PT
sum
Den
sity
(G
eV/c
)
Charged Particles (||<2.0, PT>0.5 GeV/c)
CMS Preliminarydata corrected
Tune Z1 generator level
900 GeV
7 TeV
Tune Z1
Very nice agreement!CMS corrected
data!CMS corrected
data!
CMSTune Z1
QCD@LHC 2012 MSU, August 23, 2012
Rick Field – Florida/CDF/CMS Page 16
ATLAS UE DataATLAS UE Data
ATLAS published data at 900 GeV and 7 TeV on the “transverse” charged PTsum density, dPT/dd, as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 2.5. The data are corrected and compared with PYTHIA Tune Z1 at the generrator level.
ATLAS published data at 900 GeV and 7 TeV on the “transverse” charged particle density, dN/dd, as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 2.5. The data are corrected and compared with PYTHIA Tune Z1 at the generator level.
CMS preliminary data at 900 GeV and 7 TeV on the “transverse” charged PTsum density, dPT/dd, as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 0.8. The data are corrected and compared with PYTHIA Tune Z1 at the generator level.
CMS preliminary data at 900 GeV and 7 TeV on the “transverse” charged particle density, dN/dd, as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 0.8. The data are corrected and compared with PYTHIA Tune Z1 at the generator level.
Very nice agreement!CMS corrected
data!CMS corrected
data!
"Transverse" Charged Particle Density: dN/dd
0.0
0.5
1.0
1.5
0 5 10 15 20 25 30
PTmax (GeV/c)
"Tra
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arg
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sity CMS Preliminary
corrected dataTune Z1 generator level
Charged Particles (||<0.8, PT>0.5 GeV/c)
900 GeV
7 TeV
"Transverse" Charged PTsum Density: dPT/dd
0.0
0.4
0.8
1.2
1.6
0 5 10 15 20 25 30
PTmax (GeV/c)
PT
su
m D
en
sity
(G
eV
/c)
CMS Preliminary corrected data
Tune Z1 generator level
Charged Particles (||<0.8, PT>0.5 GeV/c)
900 GeV
7 TeV
Tune Z1
CMS CMSTune Z1
"Transverse" Charged Particle Density: dN/dd
0.0
0.5
1.0
1.5
0 5 10 15 20 25 30 35
PTmax (GeV/c)
"Tra
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Tune Z1
Charged Particles (|| < 0.8, PT > 0.5 GeV/c)
7 TeV
8 TeV
Less than 4% change!
QCD@LHC 2012 MSU, August 23, 2012
Rick Field – Florida/CDF/CMS Page 20
UE Common PlotsUE Common Plots"Transverse" Charged Particle Density: dN/dd
Just before the shutdown of the Tevatron CDF has collected more than 10M “min-bias” events at several center-of-mass energies!
Proton
AntiProton
1 mile CDF
Proton AntiProton 1.96 TeV300 GeV
300 GeV 12.1M MB Events
900 GeV 54.3M MB Events
900 GeV
QCD@LHC 2012 MSU, August 23, 2012
Rick Field – Florida/CDF/CMS Page 22
New CDF UE DataNew CDF UE Data
New Corrected CDF data at 300 GeV, 900 GeV, and 1.96 TeV on the “transverse” charged particle density, dN/dd, as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 1.0.
PTmax Direction
“Toward”
“Transverse” “Transverse”
“Away”
"Transverse" Charged Particle Density: dN/dd
0.0
0.3
0.6
0.9
0 5 10 15 20 25 30 35
PTmax (GeV/c)
"Tra
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" C
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Den
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CDF Preliminary Corrected Data
Charged Particles (||<1.0, PT>0.5 GeV/c)
1.96 TeV
300 GeV
900 GeV
"Transverse" Charged Particle Density: dN/dd
0.0
0.3
0.6
0.9
0 5 10 15 20 25 30 35
PTmax (GeV/c)
"Tra
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" C
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Den
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CDF Preliminary Corrected Data
Tune Z1 Generator Level
Charged Particles (||<1.0, PT>0.5 GeV/c)
1.96 TeV
300 GeV
900 GeV
PYTHIA Tune Z1
900 GeV37,075,521 Events
300 GeV7,233,840 Events
1.96 TeV25,371,145 Events
QCD@LHC 2012 MSU, August 23, 2012
Rick Field – Florida/CDF/CMS Page 23
New CDF UE DataNew CDF UE Data
New Corrected CDF data at 300 GeV, 900 GeV, and 1.96 TeV on the “transverse” charged PTsum density, dPT/dd, as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 1.0.
PTmax Direction
“Toward”
“Transverse” “Transverse”
“Away”
"Transverse" Charged PTsum Density: dPT/dd
0.0
0.3
0.6
0.9
0 5 10 15 20 25 30 35
PTmax (GeV/c)
"Tra
nsv
erse
" P
Tsu
m D
ensi
ty (
GeV
/c)
CDF Preliminary Corrected Data
Charged Particles (||<1.0, PT>0.5 GeV/c)
1.96 TeV
300 GeV
900 GeV
"Transverse" Charged PTsum Density: dPT/dd
0.0
0.3
0.6
0.9
0 5 10 15 20 25 30 35
PTmax (GeV/c)
"Tra
nsv
erse
" P
Tsu
m D
ensi
ty (
GeV
/c)
Charged Particles (||<1.0, PT>0.5 GeV/c)
1.96 TeV
300 GeV
900 GeV
PYTHIA Tune Z1
CDF Preliminary Corrected Data
Tune Z1 Generator Level
QCD@LHC 2012 MSU, August 23, 2012
Rick Field – Florida/CDF/CMS Page 24
New CDF UE DataNew CDF UE Data
New Corrected CDF data at 300 GeV, 900 GeV, and 1.96 TeV on the “transverse” charged particle average pT, as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 1.0.
PTmax Direction
“Toward”
“Transverse” “Transverse”
“Away”
"Transverse" Charged Particle AvePT
0.6
0.8
1.0
1.2
0 5 10 15 20 25 30 35
PTmax (GeV/c)
"Tra
nsv
erse
" A
veP
T (
GeV
/c)
CDF Preliminary Corrected Data
Charged Particles (||<1.0, PT>0.5 GeV/c)
1.96 TeV
300 GeV
900 GeV
"Transverse" Charged Particle AvePT
0.6
0.8
1.0
1.2
0 5 10 15 20 25 30 35
PTmax (GeV/c)
"Tra
nsv
erse
" A
veP
T (
GeV
/c)
1.96 TeV
300 GeV
900 GeV
Charged Particles (||<1.0, PT>0.5 GeV/c)
PYTHIA Tune Z1
CDF Preliminary Corrected Data
Tune Z1 Generator Level
QCD@LHC 2012 MSU, August 23, 2012
Rick Field – Florida/CDF/CMS Page 25
Energy DependenceEnergy Dependence"Transverse" Charged Particle Density: dN/dd
0.25
0.35
0.45
0.55
0.65
0.1 1.0 10.0
Center-of-Mass Energy (TeV)
"Tra
nsv
erse
" C
har
ged
Den
sity
CDF Preliminary Corrected Data
Charged Particles (||<1.0, PT>0.5 GeV/c)
5.0 < PTmax < 6.0 GeV/c
New Corrected CDF data at 300 GeV, 900 GeV, and 1.96 TeV on the “transverse” charged particle density, dN/dd, as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 1.0.
New Corrected CDF data at 300 GeV, 900 GeV, and 1.96 TeV on the “transverse” charged particle density, dN/dd, as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 1.0 for 5.0 < PTmax < 6.0 GeV/c.
"Transverse" Charged Particle Density: dN/dd
0.0
0.3
0.6
0.9
0 5 10 15 20 25 30 35
PTmax (GeV/c)
"Tra
nsv
erse
" C
ha
rge
d D
ens
ity CDF Preliminary
Corrected Data
Charged Particles (||<1.0, PT>0.5 GeV/c)
1.96 TeV
300 GeV
900 GeV
"Transverse" Charged Particle Density: dN/dd
0.0
0.3
0.6
0.9
0 5 10 15 20 25 30 35
PTmax (GeV/c)
"Tra
nsv
ers
e"
Ch
arg
ed
Den
sit
y
CDF Preliminary Corrected Data
Tune Z1 Generator Level
Charged Particles (||<1.0, PT>0.5 GeV/c)
1.96 TeV
300 GeV
900 GeV
PYTHIA Tune Z1
"Transverse" Charged Particle Density: dN/dd
0.25
0.35
0.45
0.55
0.65
0.1 1.0 10.0
Center-of-Mass Energy (TeV)
"Tra
nsv
erse
" C
har
ged
Den
sity
Charged Particles (||<1.0, PT>0.5 GeV/c)
5.0 < PTmax < 6.0 GeV/c
CDF Preliminary Corrected Data
Tune Z1 Generator Level
PYTHIA Tune Z1
QCD@LHC 2012 MSU, August 23, 2012
Rick Field – Florida/CDF/CMS Page 26
Energy DependenceEnergy Dependence
New Corrected CDF data at 300 GeV, 900 GeV, and 1.96 TeV on the “transverse” charged PTsum density, dPT/dd, as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 1.0.
New Corrected CDF data at 300 GeV, 900 GeV, and 1.96 TeV on the “transverse” charged PTsum density, dPT/dd, as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 1.0 for 5.0 < PTmax < 6.0 GeV/c.
"Transverse" Charged PTsum Density: dPT/dd
0.0
0.3
0.6
0.9
0 5 10 15 20 25 30 35
PTmax (GeV/c)
"Tra
nsv
erse
" P
Ts
um
Den
sity
(G
eV
/c)
CDF Preliminary Corrected Data
Charged Particles (||<1.0, PT>0.5 GeV/c)
1.96 TeV
300 GeV
900 GeV
"Transverse" Charged PTsum Density: dPT/dd
0.2
0.3
0.4
0.5
0.6
0.7
0.1 1.0 10.0
Center-of-Mass Energy (TeV)
"Tra
nsv
erse
" P
Ts
um
Den
sity
(G
eV/c
)
Charged Particles (||<1.0, PT>0.5 GeV/c)
5.0 < PTmax < 6.0 GeV/c
CDF Preliminary Corrected Data
"Transverse" Charged PTsum Density: dPT/dd
0.0
0.3
0.6
0.9
0 5 10 15 20 25 30 35
PTmax (GeV/c)
"Tra
nsv
erse
" P
Ts
um
Den
sity
(G
eV/c
)
Charged Particles (||<1.0, PT>0.5 GeV/c)
1.96 TeV
300 GeV
900 GeV
PYTHIA Tune Z1
CDF Preliminary Corrected Data
Tune Z1 Generator Level
"Transverse" Charged PTsum Density: dPT/dd
0.2
0.3
0.4
0.5
0.6
0.7
0.1 1.0 10.0
Center-of-Mass Energy (TeV)
"Tra
nsv
erse
" P
Ts
um
Den
sity
(G
eV/c
)
Charged Particles (||<1.0, PT>0.5 GeV/c)
5.0 < PTmax < 6.0 GeV/c
CDF Preliminary Corrected Data
Tune Z1 Generator Level
Tune Z1
"Transverse" Charged Density
0.2
0.3
0.4
0.5
0.6
0.7
0.1 1.0 10.0
Center-of-Mass Energy (TeV)
"Tra
nsv
erse
" C
har
ged
Den
sity
Charged Particles (||<1.0, PT>0.5 GeV/c)
5.0 < PTmax < 6.0 GeV/c
PTsum
Nchg
CDF Preliminary Corrected Data
Tune Z1 Generator Level
Tune Z1
QCD@LHC 2012 MSU, August 23, 2012
Rick Field – Florida/CDF/CMS Page 27
Energy DependenceEnergy Dependence
New Corrected CDF data at 300 GeV, 900 GeV, and 1.96 TeV on the “transverse” charged particle average pT as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 1.0.
New Corrected CDF data at 300 GeV, 900 GeV, and 1.96 TeV on the “transverse” charged particle average pT as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 1.0 for 5.0 < PTmax < 6.0 GeV/c.
"Transverse" Charged Particle AvePT
0.6
0.8
1.0
1.2
0 5 10 15 20 25 30 35
PTmax (GeV/c)
"Tra
nsv
erse
" A
veP
T (
Ge
V/c
)
CDF Preliminary Corrected Data
Charged Particles (||<1.0, PT>0.5 GeV/c)
1.96 TeV
300 GeV
900 GeV
"Transverse" Charged Particle AvePT
0.85
0.90
0.95
1.00
1.05
0.1 1.0 10.0
Center-of-Mass Energy (TeV)
"Tra
nsv
erse
" A
veP
T (
Ge
V/c
)
CDF Preliminary Corrected Data
Charged Particles (||<1.0, PT>0.5 GeV/c)
5.0 < PTmax < 6.0 GeV/c
"Transverse" Charged Particle AvePT
0.85
0.90
0.95
1.00
1.05
0.1 1.0 10.0
Center-of-Mass Energy (TeV)
"Tra
nsv
erse
" A
veP
T (
Ge
V/c
)
Charged Particles (||<1.0, PT>0.5 GeV/c)
5.0 < PTmax < 6.0 GeV/c
CDF Preliminary Corrected Data
Tune Z1 Generator Level
Tune Z1
"Transverse" Charged Particle AvePT
0.6
0.8
1.0
1.2
0 5 10 15 20 25 30 35
PTmax (GeV/c)
"Tra
nsv
erse
" A
veP
T (
Ge
V/c
)
1.96 TeV
300 GeV
900 GeV
Charged Particles (||<1.0, PT>0.5 GeV/c)
PYTHIA Tune Z1
CDF Preliminary Corrected Data
Tune Z1 Generator Level
QCD@LHC 2012 MSU, August 23, 2012
Rick Field – Florida/CDF/CMS Page 28
Energy Ratio: 1960/300Energy Ratio: 1960/300
New Corrected CDF data at 300 GeV, 900 GeV, and 1.96 TeV on the “transverse” charged particle density, dN/dd, as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 1.0.
Ratio of the CDF data at 300 GeV and 1.96 TeV on the “transverse” charged particle density, dN/dd, as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 1.0. Shows 1.96 TeV divided by 300 GeV.
"Transverse" Charged Particle Density: dN/dd
0.0
0.3
0.6
0.9
0 5 10 15 20 25 30 35
PTmax (GeV/c)
"Tra
nsv
erse
" C
ha
rge
d D
ens
ity CDF Preliminary
Corrected Data
Charged Particles (||<1.0, PT>0.5 GeV/c)
1.96 TeV
300 GeV
900 GeV
"Transverse" Charged Particle Density: dN/dd
1.0
2.0
3.0
0 2 4 6 8 10 12 14
PTmax (GeV/c)
Ra
tio
CDF Preliminary Corrected Data Ratio
Charged Particles (||<1.0, PT>0.5 GeV/c)
1.96 TeV divided by 300 GeV
"Transverse" Charged Particle Density: dN/dd
0.0
0.3
0.6
0.9
0 5 10 15 20 25 30 35
PTmax (GeV/c)
"Tra
nsv
ers
e"
Ch
arg
ed
Den
sit
y
CDF Preliminary Corrected Data
Tune Z1 Generator Level
Charged Particles (||<1.0, PT>0.5 GeV/c)
1.96 TeV
300 GeV
900 GeV
PYTHIA Tune Z1
"Transverse" Charged Particle Density: dN/dd
1.0
2.0
3.0
0 2 4 6 8 10 12 14
PTmax (GeV/c)
Ra
tio
CDF Preliminary Corrected Data
Tune Z1 Generator Level
Charged Particles (||<1.0, PT>0.5 GeV/c)
1.96 TeV divided by 300 GeV
Tune Z1
QCD@LHC 2012 MSU, August 23, 2012
Rick Field – Florida/CDF/CMS Page 29
Energy Ratio: 900/300Energy Ratio: 900/300
New Corrected CDF data at 300 GeV, 900 GeV, and 1.96 TeV on the “transverse” charged particle density, dN/dd, as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 1.0.
Ratio of the CDF data at 300 GeV and 900 GeV on the “transverse” charged particle density, dN/dd, as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 1.0. Shows 900 GeV divided by 300 GeV.
"Transverse" Charged Particle Density: dN/dd
1.0
1.5
2.0
0 2 4 6 8 10 12 14
PTmax (GeV/c)
Ra
tio
CDF Preliminary Corrected Data Ratio
Charged Particles (||<1.0, PT>0.5 GeV/c)
900 GeV divided by 300 GeV
"Transverse" Charged Particle Density: dN/dd
0.0
0.3
0.6
0.9
0 5 10 15 20 25 30 35
PTmax (GeV/c)
"Tra
nsv
erse
" C
ha
rge
d D
ens
ity CDF Preliminary
Corrected Data
Charged Particles (||<1.0, PT>0.5 GeV/c)
1.96 TeV
300 GeV
900 GeV
"Transverse" Charged Particle Density: dN/dd
0.0
0.3
0.6
0.9
0 5 10 15 20 25 30 35
PTmax (GeV/c)
"Tra
nsv
erse
" C
ha
rge
d D
ens
ity
CDF Preliminary Corrected Data
Tune Z1 Generator Level
Charged Particles (||<1.0, PT>0.5 GeV/c)
1.96 TeV
300 GeV
900 GeV
PYTHIA Tune Z1
"Transverse" Charged Particle Density: dN/dd
1.0
1.5
2.0
0 2 4 6 8 10 12 14
PTmax (GeV/c)
Ra
tio
Charged Particles (||<1.0, PT>0.5 GeV/c)
900 GeV divided by 300 GeV
CDF Preliminary Corrected Data
Tune Z1 Generator LevelTune Z1
QCD@LHC 2012 MSU, August 23, 2012
Rick Field – Florida/CDF/CMS Page 30
Energy Ratio: 1960/900Energy Ratio: 1960/900
New Corrected CDF data at 300 GeV, 900 GeV, and 1.96 TeV on the “transverse” charged particle density, dN/dd, as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 1.0.
Ratio of the CDF data at 900 GeV and 1.96 TeV on the “transverse” charged particle density, dN/dd, as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 1.0. Shows 1.96 TeV divided by 900 GeV.
PTmax versus Leading JetPTmax versus Leading Jet"Transverse" Charged Particle Density: dN/dd
0.0
0.3
0.6
0.9
1.2
0 50 100 150 200 250 300 350 400
PT(jet#1) (GeV/c)
"Tra
nsv
erse
" C
har
ged
Den
sity
Charged Particles (||<1.0, PT>0.5 GeV/c)
1.96 TeV
CDF PublishedCorrected Data
PYTHIA Tune Z1
Published CDF Run 2 data at 1.96 TeV on the “transverse” charged particle density, dN/dd, as defined by the leading calorimeter jet (jet#1) for charged particles with pT > 0.5 GeV/c and || < 1.0 compared with PYTHIA Tune Z1.
"Transverse" Charged Particle Density: dN/dd
0.0
0.3
0.6
0.9
1.2
0 5 10 15 20 25 30 35
PTmax (GeV/c)
"Tra
nsv
erse
" C
har
ged
Den
sity
Charged Particles (||<1.0, PT>0.5 GeV/c)
CDF PreliminaryCorrected Data
Tune Z1 generator level
1.96 TeV
PYTHIA Tune Z1
New CDF data 1.96 TeV on the “transverse” charged particle density, dN/dd, as defined by the leading charged particle (PTmax) for charged particles with pT > 0.5 GeV/c and || < 1.0 compared with PYTHIA Tune Z1.
Yikes!???
"Transverse" Charged Particle Density: dN/dd
0.0
0.3
0.6
0.9
1.2
0 50 100 150 200 250 300 350 400
PTmax or PT(jet#1) (GeV/c)
"Tra
nsv
erse
" C
har
ged
Den
sity
Charged Particles (||<1.0, PT>0.5 GeV/c)
Leading JetPTmax1.96 TeV
CDF PreliminaryCorrected Data
PYTHIA Tune Z1
"Transverse" Charged Particle Density: dN/dd
0.0
0.3
0.6
0.9
1.2
0 10 20 30 40 50 60 70 80 90 100
PTmax or PT(jet#1) (GeV/c)
"Tra
nsv
erse
" C
har
ged
Den
sity
Charged Particles (||<1.0, PT>0.5 GeV/c)
Leading Jet
PTmax
1.96 TeV
CDF PreliminaryCorrected Data
PYTHIA Tune Z1
"Transverse" Charged Particle Density: dN/dd
0.0
0.3
0.6
0.9
1.2
0 5 10 15 20 25 30 35 40
PTmax or PT(jet#1) (GeV/c)
"Tra
nsv
erse
" C
har
ged
Den
sity
Charged Particles (||<1.0, PT>0.5 GeV/c) Leading Jet
PTmax
1.96 TeV
CDF PreliminaryCorrected Data
PYTHIA Tune Z1
OkayNo inconsistency
But need to understand!
QCD@LHC 2012 MSU, August 23, 2012
Rick Field – Florida/CDF/CMS Page 35
More Coming Soon!More Coming Soon!CDF - Many More UE Observables: Nchg density, PTsum
density, average pT, “toward”, “away”, “transverse”, “transMAX”, “transMIN”, distributions, etc..
CDF - Two Ranges: Must do (pT > 0.5 GeV/c, || < 0.8) as well as (pT > 0.5 GeV, || < 1).
CDF - Min-Bias: Many MB observables: Multiplicity, dN/d, pT distribution, <pT> versus Nchg, etc.
Soon we will have MB & UE data at300 GeV, 900 GeV, 1.96 TeV, 7 TeV, and 8 TeV!
We can study the energy dependence more precisely than ever before!
What we are learning shouldallow for a deeper understanding of MPI
which will result in more precisepredictions at the future LHC energy of 13 TeV!