CDF Run 2
Monte-Carlo Tunes
Drell-Yan Production
Lepton-Pair
Outline of Talk
PT(pair)
Proton
AntiProton
Underlying Event
Underlying Event
Initial-State
Radiation
Final-State
Radiation
¨ PT(Z-boson): Tuning to fit the
PT(Z) distribution.
Outgoing Parton
Drell-Yan Production
¨ Drell-Yan: Tuning to fit the
Lepton
Proton
AntiProton
Underlying Event
Underlying Event
Initial-State
Radiation
¨ Jet Production: Tuning to fit the
“underlying event” in high pT jet
production.
Anti-Lepton
“Hard” Scattering
“underlying event” in
Drell-Yan production.
CDF Run 2 Tunes
PYTHIA Tune A
PYTHIA Tune A25
PYTHIA Tune A50
PYTHIA Tune AW
PYTHIA Tune Q
PYTHIA Tune QW
JIMMY Default
JIMMY 325
Outgoing Parton
PT(hard)
Proton
AntiProton
Underlying Event
Underlying Event
Initial-State
Radiation
¨ Energy: Tuning to fit the energy in the
“underlying event”.
Final-State
Radiation
Outgoing Parton
CDF Joint Physics Meeting
November 4, 2005
Rick Field - Florida/CDF
Page 1
CDF Run 1 PT(Z)
PYTHIA 6.2 CTEQ5L
ISR Parameter
Parameter
Tune A
Tune
A25
Tune
A50
MSTP(81)
1
1
1
MSTP(82)
4
4
4
PARP(82)
2.0 GeV
2.0 GeV
2.0 GeV
PARP(83)
0.5
0.5
0.5
PARP(84)
0.4
0.4
0.4
PARP(85)
0.9
0.9
0.9
PARP(86)
0.95
0.95
0.95
PARP(89)
1.8 TeV
1.8 TeV
1.8 TeV
PARP(90)
0.25
0.25
0.25
PARP(67)
4.0
4.0
4.0
MSTP(91)
1
1
1
PARP(91)
1.0
2.5
5.0
PARP(93)
5.0
15.0
25.0
Z-Boson Transverse Momentum
σ = 1.0
0.12
PT Distribution 1/N dN/dPT
UE Parameters
CDF Run 1 Data
PYTHIA Tune A
σ = 2.5
PYTHIA Tune A25
PYTHIA Tune A50
0.08
CDF Run 1
published
1.8 TeV
σ = 5.0
Normalized to 1
0.04
0.00
0
2
4
6
8
10
12
14
16
18
Z-Boson PT (GeV/c)
¨ Shows the Run 1 Z-boson pT distribution
(<pT(Z)> ≈ 11.5 GeV/c) compared with
PYTHIA Tune A (<pT(Z)> = 9.7 GeV/c),
Tune A25 (<pT(Z)> = 10.1 GeV/c), and
Tune A50 (<pT(Z)> = 11.2 GeV/c).
Intrensic KT
CDF Joint Physics Meeting
November 4, 2005
Rick Field - Florida/CDF
Page 2
20
CDF Run 1 PT(Z)
PYTHIA 6.2 CTEQ5L
Parameter
MSTP(81)
ISR Parameter
Tune A
1
Tune
A25
Tune
A50
1
1
MSTP(82)
4
4
4
PARP(82)
2.0 GeV
2.0 GeV
2.0 GeV
PARP(83)
0.5
0.5
0.5
PARP(84)
0.4
0.4
0.4
PARP(85)
0.9
0.9
0.9
PARP(86)
0.95
0.95
0.95
PARP(89)
1.8 TeV
1.8 TeV
1.8 TeV
PARP(90)
0.25
0.25
0.25
PARP(67)
4.0
4.0
4.0
MSTP(91)
1
1
1
PARP(91)
1.0
2.5
5.0
PARP(93)
5.0
15.0
25.0
Z-Boson Transverse Momentum
1.0E+00
PT Distribution 1/N dN/dPT
UE Parameters
High pT shape agrees!
CDF Run 1 Data
PYTHIA Tune A
1.0E-01
CDF Run 1
published
PYTHIA Tune A25
PYTHIA Tune A50
1.0E-02
1.8 TeV
Normalized to 1
1.0E-03
1.0E-04
1.0E-05
0
10
20
30
40
50
60
70
80
90
Z-Boson PT (GeV/c)
¨ Shows the Run 1 Z-boson pT distribution
(<pT(Z)> ≈ 11.5 GeV/c) compared with
PYTHIA Tune A (<pT(Z)> = 9.7 GeV/c),
Tune A25 (<pT(Z)> = 10.1 GeV/c), and
Tune A50 (<pT(Z)> = 11.2 GeV/c).
Intrensic KT
CDF Joint Physics Meeting
November 4, 2005
Rick Field - Florida/CDF
Page 3
100
CDF Run 1 PT(Z)
PYTHIA 6.2 CTEQ5L
Parameter
Tune AW
Z-Boson Transverse Momentum
0.12
MSTP(81)
1
1
MSTP(82)
4
4
PARP(82)
2.0 GeV
2.0 GeV
PARP(83)
0.5
0.5
PARP(84)
0.4
0.4
PARP(85)
0.9
0.9
PARP(86)
0.95
0.95
PARP(89)
1.8 TeV
1.8 TeV
PARP(90)
0.25
0.25
PARP(62)
1.0
1.25
PARP(64)
1.0
0.2
PARP(67)
4.0
4.0
¨ Shows the Run 1 Z-boson pT distribution
(<pT(Z)> ≈ 11.5 GeV/c) compared with
PYTHIA Tune AW (<pT(Z)> = 11.7 GeV/c).
MSTP(91)
1
1
Effective Q cut-off, below which space-like showers are not evolved.
PARP(91)
1.0
2.1
PARP(93)
5.0
15.0
PT Distribution 1/N dN/dPT
UE Parameters
Tune A
CDF Run 1 Data
PYTHIA Tune AW
0.08
CDF Run 1
published
σ = 2.1
1.8 TeV
Normalized to 1
0.04
0.00
ISR Parameters
Intrensic KT
CDF Joint Physics Meeting
November 4, 2005
0
2
4
6
8
10
12
14
16
18
20
Z-Boson PT (GeV/c)
The Q2 = kT2 in αs for space-like showers is scaled by PARP(64)!
Rick Field - Florida/CDF
Page 4
CDF Run 1 PT(Z)
PYTHIA 6.2 CTEQ5L
Tune A
Tune AW
MSTP(81)
1
1
MSTP(82)
4
4
PARP(82)
2.0 GeV
2.0 GeV
PARP(83)
0.5
0.5
PARP(84)
0.4
0.4
PARP(85)
0.9
0.9
PARP(86)
0.95
0.95
PARP(89)
1.8 TeV
1.8 TeV
PARP(90)
0.25
0.25
PARP(62)
1.0
1.25
PARP(64)
1.0
0.2
PARP(67)
4.0
4.0
MSTP(91)
1
1
PARP(91)
1.0
2.1
PARP(93)
5.0
15.0
Z-Boson Transverse Momentum
1.0E+00
PT Distribution 1/N dN/dPT
Parameter
UE Parameters
CDF Run 1
CDF Run 1 Data
PYTHIA Tune AW
1.0E-01
published
1.8 TeV
1.0E-02
Normalized to 1
1.0E-03
1.0E-04
1.0E-05
ISR Parameters
Intrensic KT
CDF Joint Physics Meeting
November 4, 2005
0
10
20
30
40
50
60
70
80
90
100
Z-Boson PT (GeV/c)
¨ Shows the Run 1 Z-boson pT distribution
(<pT(Z)> ≈ 11.5 GeV/c) compared with
PYTHIA Tune AW (<pT(Z)> = 11.7 GeV/c).
Rick Field - Florida/CDF
Page 5
CDF Run 1 PT(Z)
PYTHIA 6.2 CTEQ5L
Parameter
Tune A25
Tune AW
MSTP(81)
1
1
MSTP(82)
4
4
PARP(82)
2.0 GeV
2.0 GeV
PARP(83)
0.5
0.5
PARP(84)
0.4
0.4
PARP(85)
0.9
0.9
PARP(86)
0.95
0.95
σ = 2.5
0.12
PT Distribution 1/N dN/dPT
UE Parameters
Z-Boson Transverse Momentum
CDF Run 1 Data
PYTHIA Tune A25
PYTHIA Tune AW
0.08
CDF Run 1
published
σ = 2.1
1.8 TeV
Normalized to 1
0.04
0.00
PARP(89)
1.8 TeV
1.8 TeV
PARP(90)
0.25
0.25
PARP(62)
1.0
1.25
PARP(64)
1.0
0.2
PARP(67)
4.0
4.0
MSTP(91)
1
1
PARP(91)
2.5
2.1
PARP(93)
5.0
Intrensic KT
CDF Joint Physics Meeting
November 4, 2005
15.0
ISR Parameters
0
2
4
6
8
10
12
14
16
18
20
Z-Boson PT (GeV/c)
¨ Shows the Run 1 Z-boson pT distribution
(<pT(Z)> ≈ 11.5 GeV/c) compared with
PYTHIA Tune AW (<pT(Z)> = 11.7 GeV/c) and
PYTHIA Tune A25 (<pT(Z)> = 10.1 GeV/c).
Rick Field - Florida/CDF
Page 6
CDF Run 1 PT(Z)
PYTHIA 6.2 CTEQ5L
UE Parameters
ISR Parameters
Tune A25
Tune AW
MSTP(81)
1
1
MSTP(82)
4
4
PARP(82)
2.0 GeV
2.0 GeV
PARP(83)
0.5
0.5
PARP(84)
0.4
0.4
PARP(85)
0.9
0.9
PARP(86)
0.95
0.95
PARP(89)
1.8 TeV
1.8 TeV
PARP(90)
0.25
0.25
PARP(62)
1.0
1.25
PARP(64)
1.0
0.2
PARP(67)
4.0
4.0
MSTP(91)
1
1
PARP(91)
2.5
2.1
PARP(93)
5.0
15.0
Intrensic KT
CDF Joint Physics Meeting
November 4, 2005
Z-Boson Transverse Momentum
1.0E+00
PT Distribution 1/N dN/dPT
Parameter
PYTHIA Tune A25
PYTHIA Tune AW
1.0E-01
RDF Preliminary
generator level
1.8 TeV
1.0E-02
Normalized to 1
1.0E-03
1.0E-04
1.0E-05
0
10
20
30
40
50
60
70
80
90
100
Z-Boson PT (GeV/c)
¨ Compares PYTHIA Tune AW with PYTHIA
Tune A25 (both normalized to one).
Rick Field - Florida/CDF
Page 7
CDF Run 1 PT(Z)
PYTHIA 6.2 CTEQ5L
ISR Parameters
Tune A25
Tune AW
MSTP(81)
1
1
MSTP(82)
4
4
PARP(82)
2.0 GeV
2.0 GeV
PARP(83)
0.5
0.5
PARP(84)
0.4
0.4
PARP(85)
0.9
0.9
PARP(86)
0.95
0.95
PARP(89)
1.8 TeV
1.8 TeV
PARP(90)
0.25
0.25
PARP(62)
1.0
1.25
PARP(64)
1.0
0.2
PARP(67)
4.0
4.0
MSTP(91)
1
1
PARP(91)
2.5
2.1
PARP(93)
5.0
15.0
Intrensic KT
CDF Joint Physics Meeting
November 4, 2005
Z-Boson Transverse Momentum
1.0E+00
PT Distribution 1/N dN/dPT
UE Parameters
Parameter
PYTHIA Tune A25
PYTHIA Tune AW
1.0E-01
RDF Preliminary
generator level
1.8 TeV
1.0E-02
Arbitrary Normalization
1.0E-03
1.0E-04
1.0E-05
0
10
20
30
40
50
60
70
80
90
100
Z-Boson PT (GeV/c)
¨ Compares PYTHIA Tune AW with PYTHIA
Tune A25 (normalized to agree at high PT(Z)).
Rick Field - Florida/CDF
Page 8
Run 2 Drell-Yan
Drell-Yan Production
Lepton
Lepton-Pair Transverse
Momentum
Proton
<PT(pair)> versus M(pair)
AntiProton
Underlying Event
Underlying Event
Initial-State
Radiation
Anti-Lepton
Lepton-Pair Transverse Momentum
Lepton-Pair Transverse Momentum
20
20
RDF Preliminary
RDF Preliminary
PY Tune AW
15
Average Pair PT
Average Pair PT
PY Tune AW
generator level
generator level
10
PY Tune A
5
15
10
PY Tune A5
5
Drell-Yan
1.96 TeV
Drell-Yan
1.96 TeV
0
0
0
50
100
150
200
250
0
50
100
150
200
250
Lepton-Pair Invariant Mass (GeV)
Lepton-Pair Invariant Mass (GeV)
¨ Shows the lepton-pair average PT versus the ¨ Shows the lepton-pair average PT versus the
lepton-pair invariant mass at 1.96 TeV for
lepton-pair invariant mass at 1.96 TeV for
PYTHIA Tune AW and PYTHIA Tune A5.
PYTHIA Tune AW and PYTHIA Tune A.
CDF Joint Physics Meeting
November 4, 2005
Rick Field - Florida/CDF
Page 9
Run 2 Drell-Yan
Drell-Yan Production
Lepton
<Densities> versus M(pair)
The “Underlying Event”
Proton
AntiProton
Underlying Event
Underlying Event
Initial-State
Radiation
Anti-Lepton
Charged Particle Density: dN/dηdφ
Charged PTsum Density: dPT/dηdφ
1.6
RDF Preliminary
generator level
0.8
Charged PTsum Density (GeV/c)
Charged Particle Density
1.0
PY Tune AW
0.6
0.4
PY Tune A
Drell-Yan
1.96 TeV
0.2
Charged Particles (|η|<1.0, PT>0.5 GeV/c)
0.0
RDF Preliminary
generator level
1.2
PY Tune AW
0.8
PY Tune A
0.4
Drell-Yan
1.96 TeV
Charged Particles (|η|<1.0, PT>0.5 GeV/c)
0.0
0
50
100
150
200
250
0
Lepton-Pair Invariant Mass (GeV)
50
100
150
200
250
Lepton-Pair Invariant Mass (GeV)
¨ Shows the charged particle density versus the ¨ Shows the charged PTsum density versus the
lepton-pair invariant mass at 1.96 TeV for
lepton-pair invariant mass at 1.96 TeV for
PYTHIA Tune AW and PYTHIA Tune A.
PYTHIA Tune AW and PYTHIA Tune A.
CDF Joint Physics Meeting
November 4, 2005
Rick Field - Florida/CDF
Page 10
High PT Drell-Yan
Lepton-Pair
Direction
∆φ
“Toward”
“Transverse”
"Toward" Charged Particle Density: dN/dηdφ
1.0
"Toward" Charged Density
The “Underlying Event” in High
PT Lepton-Pair Production
Drell-Yan
1.96 TeV
RDF Preliminary
generator level
0.8
PY Tune AW
0.6
0.4
70 < M(pair) < 110 GeV
PY Tune A
0.2
Charged Particles (|η|<1.0, PT>0.5 GeV/c)
“Transverse”
0.0
0
25
50
“Away”
75
100
125
150
Lepton-Pair PT (GeV/c)
"Toward" PTsum Density: dPT/dηdφ
PT(pair)
Proton
AntiProton
Underlying Event
Underlying Event
Initial-State
Radiation
Final-State
Radiation
Outgoing Parton
"Toward" PTsum Density (GeV/c)
Drell-Yan Production
Lepton-Pair
1.6
generator level
1.2
PY Tune AW
0.8
70 < M(pair) < 110 GeV
0.4
PY Tune A
Charged Particles (|η|<1.0, PT>0.5 GeV/c)
0.0
0
“Toward” <Densities> vs PT(pair)
CDF Joint Physics Meeting
November 4, 2005
Drell-Yan
1.96 TeV
RDF Preliminary
Rick Field - Florida/CDF
25
50
75
100
125
150
Lepton-Pair PT (GeV/c)
Page 11
High PT Drell-Yan
Lepton-Pair
Direction
∆φ
“Toward”
“Transverse”
“Transverse”
"Transverse" Charged Particle Density: dN/dηdφ
1.0
"Transverse" Charged Density
The “Underlying Event” in High
PT Lepton-Pair Production
RDF Preliminary
0.8
Drell-Yan
1.96 TeV
PY Tune AW
generator level
0.6
0.4
PY Tune A
70 < M(pair) < 110 GeV
0.2
Charged Particles (|η|<1.0, PT>0.5 GeV/c)
0.0
0
“Away”
25
50
75
100
125
150
Lepton-Pair PT (GeV/c)
"Transverse" PTsum Density: dPT/dηdφ
Lepton-Pair
PT(pair)
Proton
AntiProton
Underlying Event
Underlying Event
Initial-State
Radiation
Final-State
Radiation
Outgoing Parton
"Transverse" PTsum Density (GeV/c)
Drell-Yan Production
1.6
generator level
PY Tune AW
1.2
0.8
0.4
70 < M(pair) < 110 GeV
PY Tune A
Charged Particles (|η|<1.0, PT>0.5 GeV/c)
0.0
0
“Transverse” <Densities> vs PT(pair)
CDF Joint Physics Meeting
November 4, 2005
Drell-Yan
1.96 TeV
RDF Preliminary
Rick Field - Florida/CDF
25
50
75
100
125
150
Lepton-Pair PT (GeV/c)
Page 12
High PT Jets
Jet #1 Direction
∆φ
“Toward”
“Transverse”
“Transverse”
"Transverse" Charged Particle Density: dN/dηdφ
1.0
"Transverse" Charged Density
The “Underlying Event” in High
PT Jet Production
PY Tune AW
RDF Preliminary
generator level
0.8
0.6
PY Tune A
0.4
"Leading Jet"
CTEQ5L
1.96 TeV
Charged Particles (|η|<1.0, PT>0.5 GeV/c)
0.2
0.0
“Away”
0
50
100
150
200
250
300
350
400
450
500
PT(particle jet#1) (GeV/c)
"Transverse" PTsum Density: dPT/dηdφ
1.6
Outgoing Parton
PT(hard)
Proton
AntiProton
Underlying Event
Underlying Event
Initial-State
Radiation
Final-State
Radiation
Outgoing Parton
PY Tune AW
RDF Preliminary
generator level
1.2
PY Tune A
0.8
CTEQ5L
0.4
"Leading Jet"
1.96 TeV
Charged Particles (|η|<1.0, PT>0.5 GeV/c)
0.0
“Transverse” <Densities> vs PT(jet#1)
CDF Joint Physics Meeting
November 4, 2005
"Transverse" PTsum Density (GeV/c)
“Hard” Scattering
0
50
Rick Field - Florida/CDF
100
150
200
250
300
350
400
450
500
PT(particle jet#1) (GeV/c)
Page 13
Drell-Yan vs Jets
The “Underlying Event” in High PT Lepton-Pair and Jet Production
"Transverse" PTsum Density: dPT/dηdφ
1.6
Drell-Yan
1.96 TeV
RDF Preliminary
generator level
PY Tune AW
1.2
0.8
0.4
70 < M(pair) < 110 GeV
PY Tune A
Charged Particles (|η|<1.0, PT>0.5 GeV/c)
"Transverse" PTsum Density (GeV/c)
"Transverse" PTsum Density (GeV/c)
"Transverse" PTsum Density: dPT/dηdφ
1.6
PY Tune AW
RDF Preliminary
generator level
1.2
PY Tune A
0.8
CTEQ5L
0.4
"Leading Jet"
1.96 TeV
Charged Particles (|η|<1.0, PT>0.5 GeV/c)
0.0
0.0
0
25
50
75
100
125
150
0
50
“Transverse” <Densities> vs PT(pair)
Lepton-Pair
Direction
100
150
200
250
400
450
500
Jet #1 Direction
∆φ
“Toward”
“Toward”
“Transverse”
“Transverse”
“Transverse”
“Away”
“Away”
CDF Joint Physics Meeting
November 4, 2005
350
“Transverse” <Densities> vs PT(jet#1)
∆φ
“Transverse”
300
PT(particle jet#1) (GeV/c)
Lepton-Pair PT (GeV/c)
Rick Field - Florida/CDF
Page 14
CTEQ6.1 Tune
I used LHAPDF! See the
next talk by Craig Group!
PYTHIA 6.2 CTEQ6.1
MSTP(81)
1
1
MSTP(82)
4
4
PARP(82)
1.2 GeV
1.2 GeV
PARP(83)
0.5
0.5
PARP(84)
PARP(85)
ISR Parameters
Tune QW
0.4
0.9
0.4
0.9
PARP(86)
0.95
0.95
PARP(89)
1.8 TeV
1.8 TeV
PARP(90)
PARP(62)
0.25
1.0
0.25
1.25
PARP(64)
1.0
0.2
PARP(67)
4.0
4.0
MSTP(91)
1
1
"Transverse" Charged Particle Density: dN/dηdφ
1.0
"Transverse" Charged Density
UE Parameters
Tune Q
PY Tune Q
CTEQ61
RDF Preliminary
generator level
0.8
0.6
0.4
PY Tune A
CTEQ5L
PY Tune A
CTEQ61
"Leading Jet"
0.2
1.96 TeV
Charged Particles (|η|<1.0, PT>0.5 GeV/c)
0.0
0
50
100
150
200
250
300
350
400
450
500
PT(particle jet#1) (GeV/c)
"Transverse" PTsum Density: dPT/dηdφ
1.6
"Transverse" PTsum Density (GeV/c)
Parameter
PY Tune Q
CTEQ61
RDF Preliminary
generator level
1.2
PY Tune A
CTEQ5L
0.8
PY Tune A
CTEQ61
0.4
"Leading Jet"
1.96 TeV
Charged Particles (|η|<1.0, PT>0.5 GeV/c)
0.0
PARP(91)
1.0
2.1
0
50
100
150
200
250
300
350
400
450
500
PT(particle jet#1) (GeV/c)
PARP(93)
5.0
Intrensic KT
CDF Joint Physics Meeting
November 4, 2005
15.0
Rick Field - Florida/CDF
Page 15
JIMMY at CDF
The Energy in the “Underlying
Event” in High PT Jet Production
Jet #1 Direction
JIMMY: MPI
J. M. Butterworth
J. R. Forshaw
M. H. Seymour
∆φ
PT(JIM)= 2.5 GeV/c.
“Toward”
“Transverse”
“Transverse”
“Away”
1.96 TeV
2.0
PY Tune A
JM325
"Leading Jet"
1.0
CDF Run 2 Preliminary
MidPoint R = 0.7 |η(jet)| < 2
generator level theory
All Particles (|η|<1.0)
0
100
200
300
400
500
PT(particle jet#1) (GeV/c)
"Transverse" PTsum Density: dPT/dηdφ
Outgoing Parton
AntiProton
Underlying Event
Initial-State
Radiation
Final-State
Radiation
Outgoing Parton
“Transverse” <Densities> vs PT(jet#1)
"Transverse" PTsum Density (GeV/c)
1.6
PT(hard)
CDF Joint Physics Meeting
November 4, 2005
HW
0.0
“Hard” Scattering
Underlying Event
JIMMY Default
3.0
PT(JIM)= 3.25 GeV/c.
Proton
JIMMY was tuned to fit
the energy density in the
“transverse” region for
“leading jet” events!
"Transverse" ETsum Density: dET/dηdφ
4.0
"Transverse" ETsum Density (GeV)
JIMMY
Runs with HERWIG and adds
multiple parton interactions!
JIMMY Default
1.96 TeV
1.2
JM325
PY Tune A
0.8
"Leading Jet"
HW
0.4
MidPoint R = 0.7 |η(jet)| < 2
CDF Run 2 Preliminary
generator level theory
Charged Particles (|η|<1.0, PT>0.5 GeV/c)
0.0
0
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Rick Field - Florida/CDF
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150
200
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400
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PT(particle jet#1) (GeV/c)
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JIMMY at CDF
Jet #1 Direction
∆φ
“Toward”
“Transverse”
“Transverse”
"Transverse" Charged Particle Density: dN/dηdφ
1.2
"Transverse" Charged Density
The “Underlying Event” in High
PT Jet Production
“Away”
1.96 TeV
JIMMY Default
JM325
"Leading Jet"
0.8
PY Tune A
HW
0.4
MidPoint R = 0.7 |η(jet)| < 2
CDF Run 2 Preliminary
generator level theory
Charged Particles (|η|<1.0, PT>0.5 GeV/c)
0.0
0
50
100
150
200
250
300
350
400
450
500
PT(particle jet#1) (GeV/c)
"Transverse" PTsum Density: dPT/dηdφ
Outgoing Parton
1.6
PT(hard)
Proton
AntiProton
Underlying Event
Underlying Event
Initial-State
Radiation
Final-State
Radiation
Outgoing Parton
“Transverse” <Densities> vs PT(jet#1)
CDF Joint Physics Meeting
November 4, 2005
"Transverse" PTsum Density (GeV/c)
“Hard” Scattering
JIMMY Default
1.96 TeV
1.2
JM325
PY Tune A
0.8
"Leading Jet"
HW
0.4
MidPoint R = 0.7 |η(jet)| < 2
CDF Run 2 Preliminary
generator level theory
Charged Particles (|η|<1.0, PT>0.5 GeV/c)
0.0
0
50
Rick Field - Florida/CDF
100
150
200
250
300
350
400
450
500
PT(particle jet#1) (GeV/c)
Page 17
Summary
¨ PYTHIA Tune AW correctly describes the Z-boson PT
distribution and also fits the “underlying event” as well
as Tune A does! I do not see anything wrong with it,
except that it may only work at the Tevatron. You can
not trust the energy dependence!
Good way to study the
“underlying event”!
Drell-Yan Production
Proton
AntiProton
Underlying Event
Underlying Event
Initial-State
Radiation
¨ PYTHIA Tune Q works as well as Tune A but uses
CTEQ6.1! However, it used NLO structure functions with
LLO PYTHIA! I used LO αs (perhaps I should use NLO αs
with Λ corresponding to the NLO structure function!). To
implement this in CDF we need to get LHAPDF running Proton
within CDF software!
Anti-Lepton
“Hard” Scattering
Outgoing Parton
PT(hard)
AntiProton
Underlying Event
¨ Default JIMMY (PTJIM = 2.5 GeV/c) does not fit the
CDF “underlying event” data! Default JIMMY’s
“underlying event” is much too active!
Lepton
Underlying Event
Initial-State
Radiation
Final-State
Radiation
Outgoing Parton
¨ JIMMY 325 (PTJIM = 3.25 GeV/c) fits the energy in the “underlying event” but does
so by producing too many particles (i.e. it is too soft). This is still and improvement
over HERWIG! I ran with HERWIG 6.507 (with Lina “bug”) we are waiting for
HERWIG 6.510 to be implemented within CDF software!
CDF Joint Physics Meeting
November 4, 2005
Rick Field - Florida/CDF
Page 18