ICHEP 2012
Energy Dependence of the UE
Rick Field
University of Florida
Outline of Talk
 CDF PYTHIA 6.2 Tevatron Tune
DW predictions.
Melbourne July 4-11, 2012
 CMS PYTHIA 6.4 LHC Tune Z1.
 LPCC MB&UE working group
“common plots”.
 New UE data at 300 GeV, 900 GeV, and 1.96
CDF Run 2
300 GeV, 900 GeV, 1.96 TeV
Outgoing Parton
TeV from the Tevatron Energy-Scan.
PT(hard)
Initial-State Radiation
 New comparisons with PYTHIA 6.2
Proton
AntiProton
Underlying Event
Underlying Event
Tune DW and PYTHIA 6.4 Tune Z1.
 Much more coming soon!
ICHEP 2012
Melbourne, July 5, 2012
Outgoing Parton
CMS at the LHC
900 GeV, 7 & 8 TeV
Final-State
Radiation
Rick Field – Florida/CDF/CMS
Page 1
QCD Monte-Carlo Models:
High Transverse Momentum Jets
Hard Scattering
Initial-State Radiation
Hard Scattering “Jet”
Initial-State Radiation
“Jet”
Outgoing Parton
PT(hard)
Outgoing Parton
PT(hard)
Proton
“Hard Scattering” Component
AntiProton
Final-State Radiation
Outgoing Parton
Underlying Event
Underlying Event
Proton
“Jet”
Final-State Radiation
AntiProton
Underlying Event
Outgoing Parton
Underlying Event
“Underlying Event”
 Start with the perturbative 2-to-2 (or sometimes 2-to-3) parton-parton scattering and add initial and finalstate gluon radiation (in the leading log approximation or modified leading log approximation).
 The “underlying event” consists of the “beam-beam remnants” and from particles arising from soft or
semi-soft multiple parton interactions (MPI).
The “underlying
event” is“jet”
an unavoidable
 Of course the outgoing colored partons fragment
into hadron
and inevitably “underlying event”
background to most collider observables
observables receive contributions from initial
and final-state radiation.
and having good understand of it leads to
more precise collider measurements!
ICHEP 2012
Melbourne, July 5, 2012
Rick Field – Florida/CDF/CMS
Page 2
Tuning PYTHIA 6.2:
Multiple Parton Interaction Parameters
Parameter
Default
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.
Determines the energy
Probability
that of
thethe
MPI
produces two gluons
dependence
MPI!
with color connections to the “nearest neighbors.
0.33
PARP(86)
0.66
PARP(89)
PARP(82)
PARP(90)
PARP(67)
1 TeV
1.9
GeV/c
0.16
1.0
ICHEP 2012
Melbourne, July 5, 2012
Multiple Parton Interaction
Color String
Color String
Multiple PartonDetermine
Interactionby comparing
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.
with 630 GeV data!
Color String
Hard-Scattering Cut-Off PT0
Determines the reference energy E0.
The cut-off PT0 that regulates the 2-to-2
scattering divergence 1/PT4→1/(PT2+PT02)2
Determines the energy dependence of the cut-off
PT0 as follows PT0(Ecm) = PT0(Ecm/E0)e with
e = PARP(90)
A scale factor that determines the maximum
parton virtuality for space-like showers. The
larger the value of PARP(67) the more initialstate radiation.
Rick Field – Florida/CDF/CMS
5
PYTHIA 6.206
e = 0.25 (Set A))
4
PT0 (GeV/c)
PARP(85)
Description
Take E0 = 1.8 TeV
3
2
e = 0.16 (default)
1
100
1,000
10,000
100,000
CM Energy W (GeV)
Reference point
at 1.8 TeV
Page 3
Traditional Approach
CDF Run 1 Analysis Charged Particle Df Correlations
Leading Calorimeter Jet or
Charged Jet #1
Leading Charged Particle Jet or
PT > PTmin |h| < hcut
Direction
Leading Charged Particle or
2
“Transverse” region
very sensitive to the
“underlying event”!
Away RegionZ-Boson
“Toward-Side” Jet
Df
“Toward”
“Transverse”
“Transverse”
“Away”
Leading Object
Direction
Df
“Toward”
“Transverse”
“Transverse”
Transverse
Region
f
Leading
Object
Toward Region
Transverse
Region
“Away”
Away Region
0
-hcut
“Away-Side” Jet
h
+hcut
 Look at charged particle correlations in the azimuthal angle Df relative to a leading object (i.e.
CaloJet#1, ChgJet#1, PTmax, Z-boson). For CDF PTmin = 0.5 GeV/c hcut = 1.
 Define |Df| < 60o as “Toward”, 60o < |Df| < 120o as “Transverse”, and |Df| > 120o as

“Away”.
o
All three regions have the same area in h-f space, Dh×Df = 2hcut×120 = 2hcut×2/3. Construct
densities by dividing by the area in h-f space.
ICHEP 2012
Melbourne, July 5, 2012
Rick Field – Florida/CDF/CMS
Page 4
“Transverse” Charged Density
PTmax Direction
"Transverse" Charged Particle Density: dN/dhdf
Df
1.6
“Transverse”
“Transverse”
“Away”
ChgJet#1 Direction
Df
“Toward”
“Transverse”
“Transverse”
“Away”
"Transverse" Charged Density
“Toward”
RDF Preliminary
7 TeV
py Tune DW generator level
1.2
PTmax
0.8
ChgJet#1
DY(muon-pair)
70 < M(pair) < 110 GeV
0.4
Charged Particles (|h|<1.0, PT>0.5 GeV/c)
0.0
Muon-Pair Direction
Df
0
5
10
15
20
25
30
35
40
45
50
PT(chgjet#1) or PTmax or PT(pair) (GeV/c)
“Toward”
“Transverse”
“Transverse”
“Away”
 Shows the charged particle density in the “transverse” region for charged particles (pT > 0.5
GeV/c, |h| < 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.
ICHEP 2012
Melbourne, July 5, 2012
Rick Field – Florida/CDF/CMS
Page 5
Min-Bias “Associated”
Charged Particle Density
"Transverse" Charged Particle Density: dN/dhdf
"Transverse" Charged Particle Density: dN/dhdf
1.2
RDF Preliminary
14 TeV
Min-Bias
"Transverse" Charged Density
"Transverse" Charged Density
1.2
py Tune DW generator level
10 TeV
7 TeV
0.8
1.96 TeV
0.9 TeV
0.4
0.2 TeV
Charged Particles (|h|<1.0, PT>0.5 GeV/c)
RDF Preliminary
LHC14
py Tune DW generator level
0.8
LHC10
LHC7
Tevatron
900 GeV
0.4
PTmax = 5.25 GeV/c
RHIC
Charged Particles (|h|<1.0, PT>0.5 GeV/c)
0.0
0.0
0
5
10
15
20
0
25
2
Df
“Toward”
RHIC
“Transverse”
“Transverse”
0.2 TeV → 1.96 TeV
(UE increase ~2.7 times)
Tevatron
“Away”
6
8
10
12
14
Center-of-Mass Energy (TeV)
PTmax (GeV/c)
PTmax Direction
4
PTmax Direction
Df
“Toward”
“Transverse”
PTmax Direction
1.96 TeV → 14 TeV
(UE increase ~1.9 times)
LHC
“Transverse”
“Away”
Df
“Toward”
“Transverse”
“Transverse”
“Away”
 Shows the “associated” charged particle density in the “transverse” region as a function of
PTmax for charged particles (pT > 0.5 GeV/c, |h| < 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
Linear scale!
level (i.e. generator level).
ICHEP 2012
Melbourne, July 5, 2012
Rick Field – Florida/CDF/CMS
Page 6
Min-Bias “Associated”
Charged Particle Density
"Transverse" Charged Particle Density: dN/dhdf
"Transverse" Charged Particle Density: dN/dhdf
1.2
RDF Preliminary
14 TeV
Min-Bias
"Transverse" Charged Density
"Transverse" Charged Density
1.2
py Tune DW generator level
10 TeV
7 TeV
0.8
1.96 TeV
0.9 TeV
0.4
0.2 TeV
Charged Particles (|h|<1.0, PT>0.5 GeV/c)
RDF Preliminary
py Tune DW generator level
LHC14
LHC10
LHC7
0.8
Tevatron
0.4
900 GeV
RHIC
PTmax = 5.25 GeV/c
Charged Particles (|h|<1.0, PT>0.5 GeV/c)
0.0
0.0
0
5
10
15
20
25
0.1
Df
“Toward”
LHC7
“Transverse”
100.0
PTmax Direction
7 TeV → 14 TeV
(UE increase ~20%)
Df
“Toward”
LHC14
“Transverse”
“Away”
10.0
Center-of-Mass Energy (TeV)
PTmax (GeV/c)
PTmax Direction
1.0
Linear on a log plot!
“Transverse”
“Transverse”
“Away”
 Shows the “associated” charged particle density in the “transverse” region as a function of
PTmax for charged particles (pT > 0.5 GeV/c, |h| < 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
Log scale!
level (i.e. generator level).
ICHEP 2012
Melbourne, July 5, 2012
Rick Field – Florida/CDF/CMS
Page 7
PYTHIA Tune DW
"Transverse" Charged Particle Density: dN/dhdf
"Transverse" Charged Particle Density: dN/dhdf
Charged Particle Density
CMS Preliminary
"Transverse" Charged Density
1.2
7 TeV
data uncorrected
pyDW + SIM
0.8
CMS
900 GeV
0.4
Charged Particles (|h|<2.0, PT>0.5 GeV/c)
1.2
RDF Preliminary
7 TeV
ATLAS corrected data
Tune DW generator level
0.8
ATLAS
900 GeV
0.4
Charged Particles (|h|<2.5, PT>0.5 GeV/c)
0.0
0.0
0
5
10
15
20
25
30
35
40
45
0
50
2
4
6
8
10
12
14
16
18
20
PTmax (GeV/c)
PT(chgjet#1) GeV/c
Charged Particle Density
 CMS preliminary data at 900 GeV and 7 TeV  ATLAS preliminary data at 900 GeV and 7
"Transverse" Charged Particle Density: dN/dhdf
TeV on the “transverse” charged particle
on the “transverse” charged
particle density,
1.2
Preliminary
density,
dN/dhdf, as defined by the leading
dN/dhdf, as defined by theRDF
leading
charged
CDF 1.96 TeV
data corrected
charged
(PTmax) for charged particles
pyDW generatorparticles
level
particle jet (chgjet#1) for charged
Leading particle
Jet
with pT > 0.5 GeV/c and |h| < 2.5. The data are
with pT > 0.5 GeV/c and0.8|h| < 2. The data are
corrected and compared with PYTHIA Tune
uncorrected and compared with PYTHIA
DW at the generator level.
Tune DW after detector simulation.
PT(chgjet#1) Direction
0.4
PTmax Direction
Df
“Toward”
“Transverse”
Df
Charged Particles (PT>0.5 GeV/c, |h| < 1.0)
0.0
“Transverse”
“Transverse”
0
“Away”
ICHEP 2012
Melbourne, July 5, 2012
“Toward”
50
100
150
200
250
PT(jet#1) GeV/c
Rick Field – Florida/CDF/CMS
300
350
“Transverse”
400
“Away”
Page 8
PYTHIA Tune DW
"Transverse" Charged Particle Density: dN/dhdf
"Transverse" Charged Particle Density: dN/dhdf
3.0
1.2
CMS Preliminary
7 TeV
data uncorrected
pyDW + SIM
Ratio: 7 TeV/900 GeV
Charged Particle Density
CMS Preliminary
0.8
Ratio
CMS
900 GeV
0.4
data uncorrected
pyDW + SIM
2.0
CMS
1.0
7 TeV / 900 GeV
Charged Particles (|h|<2.0, PT>0.5 GeV/c)
Charged Particles (|h|<2.0, PT>0.5 GeV/c)
0.0
0.0
0
5
10
15
20
25
30
35
40
45
50
0
2
4
6
8
10
12
14
16
18
PT(chgjet#1) (GeV/c)
PT(chgjet#1) GeV/c
 CMS preliminary data at 900 GeV and 7 TeV  Ratio of CMS preliminary data at 900 GeV and
7 TeV on the “transverse” charged particle
on the “transverse” charged particle density,
density, dN/dhdf, as defined by the leading
dN/dhdf, as defined by the leading charged
charged particle jet (chgjet#1) for charged
particle jet (chgjet#1) for charged particles
particles with pT > 0.5 GeV/c and |h| < 2. The
with pT > 0.5 GeV/c and |h| < 2. The data are
data are uncorrected and compared with
uncorrected and compared with PYTHIA
PYTHIA Tune DW after detector simulation.
Tune DW after detector simulation.
PT(chgjet#1) Direction
PT(chgjet#1) Direction
Df
Df
“Toward”
“Transverse”
“Toward”
“Transverse”
“Transverse”
“Away”
ICHEP 2012
Melbourne, July 5, 2012
“Transverse”
“Away”
Rick Field – Florida/CDF/CMS
Page 9
PYTHIA Tune Z1
 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)!
 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.
 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!
ICHEP 2012
Melbourne, July 5, 2012
Rick Field – Florida/CDF/CMS
PARP(90)
PARP(82)
Color
Connections
Diffraction
Outgoing Parton
PT(hard)
Initial-State Radiation
Proton
Proton
Underlying Event
Outgoing Parton
Underlying Event
Final-State
Radiation
UE&MB@CMS
Page 10
PYTHIA Tune Z1
Tune Z1
(R. Field CMS)
Tune AMBT1
(ATLAS)
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
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
Parameter
Parton Distribution Function
Parameters not
shown are the
PYTHIA 6.4 defaults!
PARP(80) – Probability colored parton from BBR
ICHEP 2012
Melbourne, July 5, 2012
Rick Field – Florida/CDF/CMS
Page 11
CMS UE Data
"Transverse" Charged PTsum Density: dPT/dhdf
"Transverse" Charged Particle Density: dN/dhdf
2.0
CMS Preliminary
CMS Preliminary
data corrected
Tune Z1 generator level
7 TeV
PTsum Density (GeV/c)
Charged Particle Density
1.6
1.2
0.8
900 GeV
CMS
0.4
Tune Z1
data corrected
Tune Z1 generator level
1.6
7 TeV
1.2
CMS
0.8
900 GeV
Tune Z1
0.4
Charged Particles (|h|<2.0, PT>0.5 GeV/c)
Charged Particles (|h|<2.0, PT>0.5 GeV/c)
0.0
0.0
0
10
20
30
40
50
60
70
80
90
100
0
10
PT(chgjet#1) GeV/c
ICHEP 2012
Melbourne, July 5, 2012
30
40
50
60
70
80
90
100
PT(chgjet#1) GeV/c
 CMS preliminary data at 900 GeV and 7
TeV on the “transverse” charged particle
density, dN/dhdf, as defined by the leading
charged particle jet (chgjet#1) for charged
particles with pT > 0.5 GeV/c and |h| < 2.0.
The data are corrected and compared with
PYTHIA Tune Z1 at the generator level.
CMS corrected
data!
20
 CMS preliminary data at 900 GeV and 7
TeV on the “transverse” charged PTsum
density, dPT/dhdf, as defined by the leading
charged particle jet (chgjet#1) for charged
particles with pT > 0.5 GeV/c and |h| < 2.0.
The data are corrected and compared with
PYTHIA Tune Z1 at the generator level.
Very nice agreement!
Rick Field – Florida/CDF/CMS
CMS corrected
data!
Page 12
ATLAS UE Data
"Transverse" Charged PTsum Density: dPT/dhdf
"Transverse" Charged Particle Density: dN/dhdf
1.5
RDF Preliminary
RDF Preliminary
7 TeV
ATLAS corrected data
Tune Z1 generator level
PTsum Density (GeV/c)
"Transverse" Charged Density
1.2
0.8
ATLAS
900 GeV
0.4
Tune Z1
7 TeV
ATLAS corrected data
Tune Z1 generator level
1.0
ATLAS
900 GeV
0.5
Tune Z1
Charged Particles (|h|<2.5, PT>0.5 GeV/c)
Charged Particles (|h|<2.5, PT>0.5 GeV/c)
0.0
0.0
0
5
10
15
20
25
0
5
10
15
20
25
PTmax (GeV/c)
PTmax (GeV/c)
 ATLAS published data at 900 GeV and 7
TeV on the “transverse” charged particle
density, dN/dhdf, as defined by the leading
charged particle (PTmax) for charged
particles with pT > 0.5 GeV/c and |h| < 2.5.
The data are corrected and compared with
PYTHIA Tune Z1 at the generator level.
 ATLAS published data at 900 GeV and 7
TeV on the “transverse” charged PTsum
density, dPT/dhdf, as defined by the leading
charged particle (PTmax) for charged
particles with pT > 0.5 GeV/c and |h| < 2.5.
The data are corrected and compared with
PYTHIA Tune Z1 at the generrator level.
ATLAS publication – arXiv:1012.0791
December 3, 2010
ICHEP 2012
Melbourne, July 5, 2012
Rick Field – Florida/CDF/CMS
Page 13
MB&UE Working Group
MB & UE Common Plots
CMS
ATLAS
 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.
Outgoing Parton
“Minimum Bias” Collisions
PT(hard)
Initial-State Radiation
Proton
Proton
Underlying Event
Outgoing Parton
ICHEP 2012
Melbourne, July 5, 2012
Proton
Proton
Underlying Event
Final-State
Radiation
Rick Field – Florida/CDF/CMS
Page 14
ALICE-ATLAS UE
"Transverse" Charged PTsum Density: dPT/dhdf
"Transverse" Charged Particle Density: dN/dhdf
1.5
RDF Preliminary
RDF Preliminary
Tune Z1 generator level
PTsum Density (GeV/c)
"Transverse" Charged Density
1.2
0.8
ALICE (red)
ATLAS (blue)
0.4
7 TeV
Charged Particles (|h| < 0.8, PT > 0.5 GeV/c)
5
10
Tune Z1 generator level
1.0
ALICE (red)
ATLAS (blue)
0.5
7 TeV
Charged Particles (|h| < 0.8, PT > 0.5 GeV/c)
0.0
0.0
0
15
20
0
25
5
10
20
25
PTmax (GeV/c)
PTmax (GeV/c)
"Transverse" Charged PTsum Density: dPT/dhdf
"Transverse" Charged Particle Density: dN/dhdf
0.8
0.8
RDF Preliminary
RDF Preliminary
Tune Z1 generator level
Tune Z1 generator level
PTsum Density (GeV/c)
"Transverse" Charged Density
15
0.6
ALICE (red)
ATLAS (blue)
0.4
0.2
900 GeV
0.6
ALICE (red)
ATLAS (blue)
0.4
0.2
900 GeV
Charged Particles (|h| < 0.8, PT > 0.5 GeV/c)
Charged Particles (|h| < 0.8, PT > 0.5 GeV/c)
0.0
0.0
0
2
4
6
8
10
0
4
6
8
10
PTmax (GeV/c)
PTmax (GeV/c)
ICHEP 2012
Melbourne, July 5, 2012
2
Rick Field – Florida/CDF/CMS
Page 15
New CMS UE Data
Less than 4% change!
"Transverse" Charged Particle Density: dN/dhdf
"Transverse" Charged PTsum Density: dPT/dhdf
"Transverse" Charged Particle Density:
dN/dhdf
2.0
1.5
corrected data
Tune Z1 generator level
1.0
0.5
0.0
0
5
10
CMS Preliminary
7 TeV
RDF Preliminary
PTsum Density (GeV/c)
CMS Preliminary
"Transverse" Charged Density
"Transverse" Charged Density
1.5
900 GeV
corrected data
Tune Z1 generator level
7 TeV
8 TeV
Tune Z1
1.0
1.5
CMS
Tune Z1
0.5
1.0
7 TeV
900 GeV
CMS
Tune Z1
0.5
Charged Particles (|h|<0.8, PT>0.5 GeV/c)
Charged Particles (|h|<0.8, PT>0.5 GeV/c)
0.0
15
20
25
30
0
10 GeV/c)
Charged
Particles
(|h| < 50.8, PT > 0.5
PTmax (GeV/c)
15
20
25
30
PTmax (GeV/c)
0.0
10 7
15  CMS
20
25
30 data at
35 900 GeV and 7
 CMS preliminary data0 at 9005 GeV and
preliminary
TeV on the “transverse” charged particle PTmax (GeV/c)
TeV on the “transverse” charged PTsum
density, dN/dhdf, as defined by the leading
density, dPT/dhdf, as defined by the leading
charged particle (PTmax) for charged
charged particle (PTmax) for charged
particles with pT > 0.5 GeV/c and |h| < 0.8.
particles with pT > 0.5 GeV/c and |h| < 0.8.
The data are corrected and compared with
The data are corrected and compared with
PYTHIA Tune Z1 at the generator level.
PYTHIA Tune Z1 at the generator level.
CMS corrected
data!
ICHEP 2012
Melbourne, July 5, 2012
Very nice agreement!
Rick Field – Florida/CDF/CMS
CMS corrected
data!
Page 16
UE Common Plots
"Transverse" Charged Particle Density: dN/dhdf
"Transverse" Charged PTsum Density: dPT/dhdf
1.6
RDF Preliminary
corrected data
Tune Z1 generator level
PTsum Density (GeV/c)
"Transverse" Charged Density
1.5
1.0
0.5
CMS (solid red)
ATLAS (solid blue)
ALICE (open black)
7 TeV
RDF Preliminary
corrected data
Tune Z1 generator level
1.2
0.8
7 TeV
0.4
CMS (solid red)
ATLAS (solid blue)
ALICE (open black)
Charged Particles (|h| < 0.8, PT > 0.5 GeV/c)
0.0
0.0
0
5
10
15
20
25
30
0
5
10
PTmax (GeV/c)
"Transverse" Charged Particle Density: dN/dhdf
RDF Preliminary
corrected data
Tune Z1 generator level
corrected data
Tune Z1 generator level
PTsum Density (GeV/c)
"Transverse" Charged Density
RDF Preliminary
0.4
CMS (solid red)
ATLAS (solid blue)
ALICE (open black)
20
25
30
"Transverse" Charged PTsum Density: dPT/dhdf
0.8
0.2
15
PTmax (GeV/c)
0.8
0.6
Charged Particles (|h| < 0.8, PT > 0.5 GeV/c)
900 GeV
0.6
0.4
0.2
CMS (solid red)
ATLAS (solid blue)
ALICE (open black)
Charged Particles (|h| < 0.8, PT > 0.5 GeV/c)
0.0
900 GeV
Charged Particles (|h| < 0.8, PT > 0.5 GeV/c)
0.0
0
2
4
6
8
10
12
14
0
2
PTmax (GeV/c)
ICHEP 2012
Melbourne, July 5, 2012
4
6
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PTmax (GeV/c)
Rick Field – Florida/CDF/CMS
Page 17
14
Tevatron Energy Scan
Proton
CDF
1 mile
AntiProton
Proton
900GeV
GeV
300
1.96
TeV
AntiProton
 Just before the shutdown of the Tevatron CDF
has collected more than 10M “min-bias” events
at several center-of-mass energies!
300 GeV 12.1M MB Events
900 GeV 54.3M MB Events
ICHEP 2012
Melbourne, July 5, 2012
Rick Field – Florida/CDF/CMS
Page 18
New CDF UE Data
1.96 TeV
25,371,145 Events
900 GeV
37,075,521 Events
"Transverse" Charged Particle Density: dN/dhdf
PTmax Direction
Df
“Toward”
“Transverse”
“Transverse”
“Away”
"Transverse" Charged Density
0.9
CDF Preliminary
1.96 TeV
Corrected Data
0.6
900 GeV
0.3
300 GeV
Charged Particles (|h|<1.0, PT>0.5 GeV/c)
0.0
0
5
10
15
20
25
30
35
PTmax (GeV/c)
 New Corrected CDF data at 300 GeV, 900 GeV, and 1.96 TeV on the “transverse”
charged particle density, dN/dhdf, as defined by the leading charged particle
(PTmax) for charged particles with pT > 0.5 GeV/c and |h| < 1.0.
300 GeV
7,233,840 Events
ICHEP 2012
Melbourne, July 5, 2012
Rick Field – Florida/CDF/CMS
Page 19
Energy Dependence
"Transverse" Charged Particle Density: dN/dhdf
"Transverse" Charged Particle Density: dN/dhdf
3.0
CDF Preliminary
CDF Preliminary
1.96 TeV
Corrected Data
Corrected Data
0.6
Ratio
"Transverse" Charged Density
0.9
900 GeV
2.0
0.3
1.96 TeV divided by 300 GeV
300 GeV
Charged Particles (|h|<1.0, PT>0.5 GeV/c)
Charged Particles (|h|<1.0, PT>0.5 GeV/c)
1.0
0.0
0
5
10
15
20
25
30
35
0
2
4
6
8
10
12
PTmax (GeV/c)
PTmax (GeV/c)
 New Corrected CDF data at 300 GeV, 900
 Ratio of the CDF data at 300 GeV and 1.96
GeV, and 1.96 TeV on the “transverse”
TeV on the “transverse” charged particle
charged particle density, dN/dhdf, as defined
density, dN/dhdf, as defined by the leading
by the leading charged particle (PTmax) for
charged particle (PTmax) for charged
charged particles with pT > 0.5 GeV/c and |h|
particles with pT > 0.5 GeV/c and |h| < 1.0.
< 1.0.
Shows 1.96 TeV divided by 300 GeV.
ICHEP 2012
Melbourne, July 5, 2012
Rick Field – Florida/CDF/CMS
Page 20
14
Energy Dependence
"Transverse" Charged Particle Density: dN/dhdf
"Transverse" Charged Particle Density: dN/dhdf
2.0
CDF Preliminary
CDF Preliminary
1.96 TeV
Corrected Data
Corrected Data
0.6
Ratio
"Transverse" Charged Density
0.9
900 GeV
1.5
0.3
900 GeV divided by 300 GeV
300 GeV
Charged Particles (|h|<1.0, PT>0.5 GeV/c)
Charged Particles (|h|<1.0, PT>0.5 GeV/c)
0.0
1.0
0
5
10
15
20
25
30
35
0
2
PTmax (GeV/c)
4
6
8
10
12
PTmax (GeV/c)
 New Corrected CDF data at 300 GeV, 900
 Ratio of the CDF data at 300 GeV and 900
GeV, and 1.96 TeV on the “transverse”
GeV on the “transverse” charged particle
charged particle density, dN/dhdf, as defined
density, dN/dhdf, as defined by the leading
by the leading charged particle (PTmax) for
charged particle (PTmax) for charged
charged particles with pT > 0.5 GeV/c and |h|
particles with pT > 0.5 GeV/c and |h| < 1.0.
< 1.0.
Shows 900 GeV divided by 300 GeV.
ICHEP 2012
Melbourne, July 5, 2012
Rick Field – Florida/CDF/CMS
Page 21
14
Energy Dependence
"Transverse" Charged Particle Density: dN/dhdf
"Transverse" Charged Particle Density: dN/dhdf
1.6
CDF Preliminary
CDF Preliminary
1.96 TeV
Corrected Data
Corrected Data
0.6
1.4
Ratio
"Transverse" Charged Density
0.9
900 GeV
0.3
1.2
1.96 TeV divided by 900 GeV
300 GeV
Charged Particles (|h|<1.0, PT>0.5 GeV/c)
Charged Particles (|h|<1.0, PT>0.5 GeV/c)
0.0
1.0
0
5
10
15
20
25
30
35
0
PTmax (GeV/c)
5
10
15
20
25
PTmax (GeV/c)
 New Corrected CDF data at 300 GeV, 900
 Ratio of the CDF data at 900 GeV and 1.96
GeV, and 1.96 TeV on the “transverse”
TeV on the “transverse” charged particle
charged particle density, dN/dhdf, as defined
density, dN/dhdf, as defined by the leading
by the leading charged particle (PTmax) for
charged particle (PTmax) for charged
charged particles with pT > 0.5 GeV/c and |h|
particles with pT > 0.5 GeV/c and |h| < 1.0.
< 1.0.
Shows 1.96 TeV divided by 900 GeV.
ICHEP 2012
Melbourne, July 5, 2012
Rick Field – Florida/CDF/CMS
Page 22
Energy Dependence
"Transverse" Charged Particle Density: dN/dhdf
"Transverse" Charged Particle Density: dN/dhdf
0.65
CDF Preliminary
"Transverse" Charged Density
"Transverse" Charged Density
0.9
1.96 TeV
Corrected Data
0.6
900 GeV
0.3
300 GeV
Charged Particles (|h|<1.0, PT>0.5 GeV/c)
CDF Preliminary
Corrected Data
0.55
0.45
0.35
5.0 < PTmax < 6.0 GeV/c
Charged Particles (|h|<1.0, PT>0.5 GeV/c)
0.25
0.0
0
5
10
15
20
25
30
35
0.1
1.0
10.0
Center-of-Mass Energy (TeV)
PTmax (GeV/c)
 New Corrected CDF data at 300 GeV, 900
 New Corrected CDF data at 300 GeV, 900
GeV, and 1.96 TeV on the “transverse”
GeV, and 1.96 TeV on the “transverse”
charged particle density, dN/dhdf, as defined
charged particle density, dN/dhdf, as defined
by the leading charged particle (PTmax) for
by the leading charged particle (PTmax) for
charged particles with pT > 0.5 GeV/c and |h|
charged particles with pT > 0.5 GeV/c and |h|
< 1.0.
< 1.0 for 5.0 < PTmax < 6.0 GeV/c.
ICHEP 2012
Melbourne, July 5, 2012
Rick Field – Florida/CDF/CMS
Page 23
PYTHIA 6.2 Tune DW
"Transverse" Charged Particle Density: dN/dhdf
"Transverse" Charged Particle Density: dN/dhdf
3.0
CDF Preliminary
CDF Preliminary
Corrected Data
Tune DW Generator Level
1.96 TeV
Tune DW
Corrected Data
Tune DW Generator Level
0.6
Ratio
"Transverse" Charged Density
0.9
900 GeV
2.0
0.3
1.96 TeV divided by 300 GeV
PYTHIA Tune DW
300 GeV
Charged Particles (|h|<1.0, PT>0.5 GeV/c)
Charged Particles (|h|<1.0, PT>0.5 GeV/c)
1.0
0.0
0
5
10
15
20
25
30
0
35
2
4
6
8
10
12
14
PTmax (GeV/c)
PTmax (GeV/c)
"Transverse" Charged Particle Density: dN/dhdf
"Transverse" Charged Particle Density: dN/dhdf
2.0
1.6
CDF Preliminary
CDF Preliminary
Tune DW
Corrected Data
Tune DW Generator Level
Tune DW
Corrected Data
Tune DW Generator Level
Ratio
Ratio
1.4
1.5
1.2
900 GeV divided by 300 GeV
1.96 TeV divided by 900 GeV
Charged Particles (|h|<1.0, PT>0.5 GeV/c)
Charged Particles (|h|<1.0, PT>0.5 GeV/c)
1.0
1.0
0
2
4
6
8
10
12
14
0
PTmax (GeV/c)
ICHEP 2012
Melbourne, July 5, 2012
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Rick Field – Florida/CDF/CMS
Page 24
PYTHIA
6.4
Tune
Z1
ATLAS
CMS
"Transverse" Charged Particle Density: dN/dhdf
"Transverse" Charged Particle Density: dN/dhdf
0.9
1.2
"Transverse"Ratio
Charged Density
0.65
3.0
CDF Preliminary
1.96 TeV
RDF Preliminary
Corrected Data
Tune Z1 Generator Level
Corrected Data
0.6
0.3
"Transverse" Charged Density
"Transverse" Charged Density
"Transverse"
"Transverse" Charged
Charged Particle
Particle Density:
Density: dN/dhdf
dN/dhdf
900 GeV
0.8
PYTHIA Tune Z1
300 GeV
0.0
0
5
10
Charged Particles (|h|<1.0, PT>0.5 GeV/c)
15
20
25
30
PTmax (GeV/c)
CDF
300 GeV
CDF Preliminary
PYTHIA Tune Z1
1.96 TeV
2
4
CDF
ChargedParticles
Particles(|h|<1.0,
(|h|<1.0,PT>0.5
PT>0.5GeV/c)
GeV/c)
Charged
6
1.0
CDF
8
10
12
14
10.0
PTmax (GeV/c)
Center-of-Mass
Energy (TeV)
"Transverse" Charged Particle Density: dN/dhdf
PYTHIA Tune Z1
1.6
CDF Preliminary
Charged
Particles
(PT>0.5 GeV/c)
Corrected
Data
Tune Z1
Tune Z1 Generator Level
0.0
5
10
15
Ratio
1.4
0
1.5
1.96
divided
by GeV/c
300 GeV
5.0 TeV
< PTmax
< 6.0
0.35
Tune Z1
Corrected Data
Tune Z1 Generator Level
Ratio
7 TeV
2.0
0.45
900 GeV
ALICE
Tune Z1
CorrectedData
Data
Corrected
Tune Z1 Generator Level
0.55 Tune Z1 Generator Level
1.0
0.25
00.1
35
0.4
"Transverse" Charged Particle Density: dN/dhdf
2.0
CDFPreliminary
Preliminary
CDF
20
25
30
35
PTmax (GeV/c)
1.2
900 GeV divided by 300 GeV
1.96 TeV divided by 900 GeV
Charged Particles (|h|<1.0, PT>0.5 GeV/c)
Charged Particles (|h|<1.0, PT>0.5 GeV/c)
1.0
1.0
0
2
4
6
8
10
12
14
0
PTmax (GeV/c)
ICHEP 2012
Melbourne, July 5, 2012
5
10
15
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PTmax (GeV/c)
Rick Field – Florida/CDF/CMS
Page 25
PTmax versus Leading Jet
"Transverse"
"Transverse" Charged
Charged Particle
Particle Density:
Density: dN/dhdf
dN/dhdf
"Transverse"
"Transverse"Charged
ChargedParticle
ParticleDensity:
Density:dN/dhdf
dN/dhdf
1.2
1.2
CDF
CDFPublished
Preliminary
"Transverse"
"Transverse" Charged
Charged Density
Density
"Transverse"
Charged
Density
"Transverse" Charged
Charged Density
Density
"Transverse"
1.2
1.2
Corrected
Corrected
Data
Data
0.9
0.9
0.6
0.6
Leading Jet
PTmax
0.3
0.3
1.96
1.96TeV
TeV
PYTHIA
PYTHIATune
TuneZ1
Z1
Charged
ChargedParticles
Particles(|h|<1.0,
(|h|<1.0,PT>0.5
PT>0.5GeV/c)
GeV/c)
CDF
Preliminary
CDF
Preliminary
CDF
Preliminary
Corrected
Data
Corrected
Data
Corrected Data
Tune Z1 generator level
0.9
0.9
PTmax
0.6
0.6
1.96
1.96
TeV
TeV
1.96
TeV
Leading Jet
0.3
0.3
PTmax
PYTHIA
Tune
PYTHIA
Tune
Z1 Z1Z1
PYTHIA
Tune
Leading Jet Charged
ChargedParticles
Particles(|h|<1.0,
(|h|<1.0,PT>0.5
PT>0.5GeV/c)
GeV/c)
Charged
Particles
(|h|<1.0,
PT>0.5
GeV/c)
0.0
0.0
0.0
0.0
00
50
50
100
100
150
150
200
200
250
250
300
300
350
350
400
400
00
10 55
20 1010
30
15
4015
50
20
2060 25
7025 30 80
90
3035
100
40
35
PTmax
PTmax
or
orPT(jet#1)
PT(jet#1)
(GeV/c)
(GeV/c)
PTmax
(GeV/c)
PTmax
PT(jet#1)
or PT(jet#1)
(GeV/c)
(GeV/c)
 Published CDF Run 2 data at 1.96 TeV on the  New CDF data 1.96 TeV on the “transverse”
“transverse” charged particle density,
charged particle density, dN/dhdf, as defined
Okay
dN/dhdf, as defined by the leading
by the leading charged particle (PTmax) for
No with
inconsistency
calorimeter jet (jet#1) for charged particles
charged particles
pT > 0.5 GeV/c and |h|
with pT > 0.5 GeV/c and |h| < 1.0 compared
ButPYTHIA
need toTune Z1.
< 1.0 compared with
with PYTHIA Tune Z1.
Yikes!
understand!
???
ICHEP 2012
Melbourne, July 5, 2012
Rick Field – Florida/CDF/CMS
Page 26
More Coming Soon!
 CDF - Many More UE Observables: Nchg density, PTsum
density, average pT, “toward”, “away”, “transverse”,
“transMAX”, “transMIN”, distributions, etc..
 CDF - Two h Ranges:
Must
(pT > 0.5
GeV/c, |h| < 0.8)
What we
are do
learning
should
as well as (pT > 0.5 allow
GeV, |h|
1). precise
for<more
predictions at the future
 CDF - Min-Bias: Many
MB observables:
LHC energy
of 13 TeV! Multiplicity,
dN/dh, pT distribution, <pT> versus Nchg, etc.
Soon we will have MB & UE data at
300 GeV, 900 GeV, 1.96 TeV, 7 TeV, and 8 TeV!
We can study the energy dependence
more precisely than ever before!
ICHEP 2012
Melbourne, July 5, 2012
Rick Field – Florida/CDF/CMS
Page 27