CDF Joint Physics Group June 27, 2003 Rick FieldPage 1 PYTHIA Tune A versus Run 2 Data Compare...
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Transcript of CDF Joint Physics Group June 27, 2003 Rick FieldPage 1 PYTHIA Tune A versus Run 2 Data Compare...
CDF Joint Physics Group June 27, 2003
Rick Field Page 1
PYTHIA Tune A versusPYTHIA Tune A versusRun 2 DataRun 2 Data
Compare PYTHIA Tune A with Run 2 data on the “underlying event”.
Outline of Talk
Compare PYTHIA Tune A with the properties of the “calorimeter jets” as measured in Run 2.
Use PYTHIA Tune A to correct the Run 2 data from measured to “true”.
Proton AntiProton
“Hard” Scattering
PT(hard)
Outgoing Parton
Outgoing Parton
Underlying Event Underlying Event
Initial-State Radiation
Final-State Radiation
Compare PYTHIA Tune A before and after CDFSIM.
Calorimeter Jet Construct “correction factors”!
JetClu R = 0.7
CDF Joint Physics Group June 27, 2003
Rick Field Page 2
““Underlying Event”Underlying Event”as defined by “Charged particle Jets”as defined by “Charged particle Jets”
Charged Jet #1Direction
“Transverse” “Transverse”
“Toward”
“Away”
“Toward-Side” Jet
“Away-Side” Jet
Look at charged particle correlations in the azimuthal angle relative to the leading charged particle jet.
Define || < 60o as “Toward”, 60o < || < 120o as “Transverse”, and || > 120o as “Away”. All three regions have the same size in - space, x = 2x120o = 4/3.
Charged Jet #1Direction
“Toward”
“Transverse” “Transverse”
“Away”
Charged Particle Correlations PT > 0.5 GeV/c || < 1
Toward-side “jet”(always)
Away-side “jet”(sometimes)
Perpendicular to the plane of the 2-to-2 hard scattering
“Transverse” region is very sensitive to the “underlying event”!
-1 +1
2
0
Leading ChgJet
Toward Region
Transverse Region
Transverse Region
Away Region
Away Region
Look at the charged particle density in the “transverse” region!
CDF Joint Physics Group June 27, 2003
Rick Field Page 3
Charged Particle Density
1.0E-05
1.0E-04
1.0E-03
1.0E-02
1.0E-01
1.0E+00
0 2 4 6 8 10 12 14
PT(charged) (GeV/c)C
har
ged
Den
sity
dN
/d d
dP
T (
1/G
eV/c
)
CDF Run 1data uncorrectedtheory corrected
1.8 TeV ||<1 PT>0.5 GeV/c
CDF Min-Bias
"Transverse"PT(chgjet#1) > 5 GeV/c
"Transverse"PT(chgjet#1) > 30 GeV/c
PYTHIA 6.206 Set A
CTEQ5L
"Transverse" Charged Particle Density: dN/dd
0.00
0.25
0.50
0.75
1.00
0 5 10 15 20 25 30 35 40 45 50
PT(charged jet#1) (GeV/c)
"Tra
nsv
erse
" C
har
ged
Den
sity
1.8 TeV ||<1.0 PT>0.5 GeV/c
CDF Run 1data uncorrectedtheory corrected
PYTHIA 6.206 Set A
Tuned PYTHIA 6.206Tuned PYTHIA 6.206Run 1 Tune ARun 1 Tune A
Compares the average “transverse” charge particle density (||<1, PT>0.5 GeV) versus PT(charged jet#1) and the PT distribution of the “transverse” and “Min-Bias” densities with the QCD Monte-Carlo predictions of a tuned version of PYTHIA 6.206 (PT(hard) > 0, CTEQ5L, Set A).
Set A Min-Bias<dNchg/dd> = 0.24
Charged Particle Density: dN/dd
0.0
0.2
0.4
0.6
0.8
1.0
-4 -3 -2 -1 0 1 2 3 4
Pseudo-Rapidity
dN
/d d
Pythia 6.206 Set A
CDF Min-Bias 1.8 TeV 1.8 TeV all PT
CDF Published
Describes “Min-Bias” collisions! Describes the “underlying event”!
“Min-Bias”
Set A PT(charged jet#1) > 30 GeV/c“Transverse” <dNchg/dd> = 0.60
Describes the rise from “Min-Bias” to “underlying event”!
CDF Joint Physics Group June 27, 2003
Rick Field Page 4
Charged Particle Jet #1 Direction
“Toward”
“Transverse” “Transverse”
“Away”
"Transverse" Charged Particle Density: dN/dd
0.00
0.25
0.50
0.75
1.00
1.25
0 5 10 15 20 25 30 35 40 45 50
PT(charged jet#1) (GeV/c)"T
ran
sver
se"
Ch
arg
ed D
ensi
ty
CDF Run 1 Min-Bias
CDF Run 1 JET20CDF Run 1 Data
data uncorrected
1.8 TeV ||<1.0 PT>0.5 GeV
"Transverse" Charged Particle Density: dN/dd
0.00
0.25
0.50
0.75
1.00
1.25
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
PT(charged jet#1) (GeV/c)"T
ran
sver
se"
Ch
arg
ed D
ensi
ty
CDF Run 1 Min-Bias
CDF Run 1 JET20
||<1.0 PT>0.5 GeV
CDF Preliminarydata uncorrected
“ “Transverse” Transverse” Charged Particle DensityCharged Particle Density
Shows the data on the average “transverse” charge particle density (||<1, PT>0.5 GeV) as a function of the transverse momentum of the leading charged particle jet from Run 1.
Compares the Run 2 data (Min-Bias, JET20, JET50, JET70, JET100) with Run 1. The errors on the (uncorrected) Run 2 data include both statistical and correlated systematic uncertainties.
"Transverse" Charged Particle Density: dN/dd
0.00
0.25
0.50
0.75
1.00
1.25
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
PT(charged jet#1) (GeV/c)"T
ran
sver
se"
Ch
arg
ed D
ensi
ty
CDF Run 2
“Transverse” region as defined by the leading “charged particle jet”
"Transverse" Charged Particle Density: dN/dd
0.00
0.25
0.50
0.75
1.00
1.25
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
PT(charged jet#1) (GeV/c)"T
ran
sver
se"
Ch
arg
ed D
ensi
ty CDF Run 1 Published
CDF Run 2 Preliminary
||<1.0 PT>0.5 GeV/c
CDF Preliminarydata uncorrected
Excellent agreement between Run 1 and 2!
"Transverse" Charged Particle Density: dN/dd
0.00
0.25
0.50
0.75
1.00
1.25
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
PT(charged jet#1) (GeV/c)"T
ran
sver
se"
Ch
arg
ed D
ensi
ty
CDF Run 1 Published
CDF Run 2 Preliminary
PYTHIA Tune A
||<1.0 PT>0.5 GeV/c
CDF Preliminarydata uncorrectedtheory corrected
PYTHIA Tune A was tuned to fit the “underlying event” in Run I!
Shows the prediction of PYTHIA Tune A at 1.96 TeV after detector simulation (i.e. after CDFSIM).
CDF Joint Physics Group June 27, 2003
Rick Field Page 5
“ “Transverse” Transverse” Charged PTsum DensityCharged PTsum Density
Shows the data on the average “transverse” charged PTsum density (||<1, PT>0.5 GeV) as a function of the transverse momentum of the leading charged particle jet from Run 1.
"Transverse" Charged PTsum Density: dPTsum/dd
0.00
0.25
0.50
0.75
1.00
1.25
0 5 10 15 20 25 30 35 40 45 50
PT(charged jet#1) (GeV/c)"T
ran
sver
se"
PT
sum
Den
sity
(G
eV) CDF JET20
CDF Min-BiasCDF Run 1 Data
data uncorrected
1.8 TeV ||<1.0 PT>0.5 GeV
Compares the Run 2 data (Min-Bias, JET20, JET50, JET70, JET100) with Run 1. The errors on the (uncorrected) Run 2 data include both statistical and correlated systematic uncertainties.
"Transverse" Charged PTsum Density: dPTsum/dd
0.00
0.25
0.50
0.75
1.00
1.25
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
PT(charged jet#1) (GeV/c)"T
ran
sver
se"
PT
sum
Den
sity
(G
eV)
CDF JET20
CDF Min-Bias
CDF Preliminarydata uncorrected
||<1.0 PT>0.5 GeV
Charged Particle Jet #1 Direction
“Toward”
“Transverse” “Transverse”
“Away”
"Transverse" Charged PTsum Density: dPTsum/dd
0.00
0.25
0.50
0.75
1.00
1.25
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
PT(charged jet#1) (GeV/c)"T
ran
sver
se"
PT
sum
Den
sity
(G
eV)
CDF Run 2
“Transverse” region as defined by the leading “charged particle jet”
"Transverse" Charged PTsum Density: dPTsum/dd
0.00
0.25
0.50
0.75
1.00
1.25
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
PT(charged jet#1) (GeV/c)"T
ran
sver
se"
PT
sum
Den
sity
(G
eV/c
)
CDF Run 1 Published
CDF Run 2 Preliminary
CDF Preliminarydata uncorrected
||<1.0 PT>0.5 GeV/c
Excellent agreement between Run 1 and 2!
"Transverse" Charged PTsum Density: dPTsum/dd
0.00
0.25
0.50
0.75
1.00
1.25
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
PT(charged jet#1) (GeV/c)"T
ran
sver
se"
PT
sum
Den
sity
(G
eV/c
)
CDF Run 1 Published
CDF Run 2 Preliminary
PYTHIA Tune A
CDF Preliminarydata uncorrectedtheory corrected
||<1.0 PT>0.5 GeV/c
Shows the prediction of PYTHIA Tune A at 1.96 TeV after detector simulation (i.e. after CDFSIM).
PYTHIA Tune A was tuned to fit the “underlying event” in Run I!
CDF Joint Physics Group June 27, 2003
Rick Field Page 6
JetClu Jet #1 Direction
“Transverse” “Transverse”
“Toward”
“Away”
“Toward-Side” Jet
“Away-Side” Jet
““Underlying Event”Underlying Event”as defined by “Calorimeter Jets”as defined by “Calorimeter Jets”
Look at charged particle correlations in the azimuthal angle relative to the leading JetClu jet.
Define || < 60o as “Toward”, 60o < || < 120o as “Transverse”, and || > 120o as “Away”. All three regions have the same size in - space, x = 2x120o = 4/3.
Charged Particle Correlations PT > 0.5 GeV/c || < 1
Away-side “jet”(sometimes)
Perpendicular to the plane of the 2-to-2 hard scattering
“Transverse” region is very sensitive to the “underlying event”!
JetClu Jet #1 Direction
“Toward”
“Transverse” “Transverse”
“Away”
-1 +1
2
0
Leading Jet
Toward Region
Transverse Region
Transverse Region
Away Region
Away Region
Look at the charged particle density in the “transverse” region!
CDF Joint Physics Group June 27, 2003
Rick Field Page 7
““Transverse” Transverse” Charged Particle DensityCharged Particle Density
Shows the data on the average “transverse” charge particle density (||<1, PT>0.5 GeV) as a function of the transverse energy of the leading JetClu jet (R = 0.7, |(jet)| < 2) from Run 2.
JetClu Jet #1 Direction
“Toward”
“Transverse” “Transverse”
“Away”
Compares the “transverse” region of the leading “charged particle jet”, chgjet#1, with the “transverse” region of the leading “calorimeter jet” (JetClu R = 0.7), jet#1.
JetClu Jet #1 or ChgJet#1
Direction
“Toward”
“Transverse” “Transverse”
“Away”
, compared with PYTHIA Tune A after CDFSIM.
"Transverse" Charged Particle Density: dN/dd
0.00
0.25
0.50
0.75
1.00
0 25 50 75 100 125 150 175 200 225 250
ET(jet#1) (GeV)
"Tra
nsv
erse
" C
har
ged
Den
sity
CDF Preliminarydata uncorrected
Charged Particles (||<1.0, PT>0.5 GeV/c)
JetClu (R = 0.7, |(jet#1)| < 2)
“Transverse” region as defined by the leading
“calorimeter jet” "Transverse" Charged Particle Density: dN/dd
0.00
0.25
0.50
0.75
1.00
0 25 50 75 100 125 150 175 200 225 250
ET(jet#1) (GeV)
"Tra
nsv
erse
" C
har
ged
Den
sity
PYTHIA Tune A
CDF Run 2 PreliminaryCDF Preliminary
data uncorrectedtheory corrected
Charged Particles (||<1.0, PT>0.5 GeV/c)
JetClu (R = 0.7, |(jet#1)| < 2)
"Transverse" Charged Particle Density: dN/dd
0.00
0.25
0.50
0.75
1.00
0 25 50 75 100 125 150 175 200 225 250
PT(chgjet#1) or ET(jet#1) (GeV)
"Tra
nsv
erse
" C
har
ged
Den
sity CDF Preliminary
data uncorrected
Charged Particles (||<1.0, PT>0.5 GeV/c)
ChgJet#1 R = 0.7
JetClu Jet#1 (R = 0.7,|(jet)|<2)
"Transverse" Charged Particle Density: dN/dd
0.00
0.25
0.50
0.75
1.00
0 25 50 75 100 125 150 175 200 225 250
PT(chgjet#1) or ET(jet#1) (GeV)
"Tra
nsv
erse
" C
har
ged
Den
sity
CDF Preliminarydata uncorrectedtheory corrected
Charged Particles (||<1.0, PT>0.5 GeV/c)
ChgJet#1 R = 0.7
JetClu Jet#1 (R = 0.7, |(jet)|<2)
PYTHIA Tune A 1.96 TeV
CDF Joint Physics Group June 27, 2003
Rick Field Page 8
““Transverse” Transverse” Charged PTsum DensityCharged PTsum Density
Shows the data on the average “transverse” charged PTsum density (||<1, PT>0.5 GeV) as a function of the transverse energy of the leading JetClu jet (R = 0.7, |(jet)| < 2) from Run 2.
JetClu Jet #1 Direction
“Toward”
“Transverse” “Transverse”
“Away”
Compares the “transverse” region of the leading “charged particle jet”, chgjet#1, with the “transverse” region of the leading “calorimeter jet” (JetClu R = 0.7), jet#1.
JetClu Jet #1 or ChgJet#1
Direction
“Toward”
“Transverse” “Transverse”
“Away”
, compared with PYTHIA Tune A after CDFSIM.
"Transverse" Charged PTsum Density: dPTsum/dd
0.0
0.5
1.0
1.5
0 25 50 75 100 125 150 175 200 225 250
ET(jet#1) (GeV)
"Tra
nsv
erse
" P
Tsu
m D
ensi
ty (
GeV
/c)
CDF Preliminarydata uncorrected
Charged Particles (||<1.0, PT>0.5 GeV/c)
JetClu (R = 0.7, |(jet#1)| < 2)
“Transverse” region as defined by the leading
“calorimeter jet” "Transverse" Charged PTsum Density: dPTsum/dd
0.0
0.5
1.0
1.5
0 25 50 75 100 125 150 175 200 225 250
ET(jet#1) (GeV)
"Tra
nsv
erse
" P
Tsu
m D
ensi
ty (
GeV
/c)
PYTHIA Tune A
CDF Run 2 Preliminary
CDF Preliminarydata uncorrectedtheory corrected
Charged Particles (||<1.0, PT>0.5 GeV/c)
JetClu (R = 0.7, |(jet#1)| < 2)
"Transverse" Charged PTsum Density: dPTsum/dd
0.0
0.5
1.0
1.5
0 25 50 75 100 125 150 175 200 225 250
PT(chgjet#1) or ET(jet#1) (GeV)
"Tra
nsv
erse
" P
Tsu
m D
ensi
ty (
GeV
/c)
CDF Preliminarydata uncorrected
Charged Particles (||<1.0, PT>0.5 GeV/c) ChgJet#1 R = 0.7
JetClu Jet#1 (R = 0.7,|(jet)|<2)
"Transverse" Charged PTsum Density: dPTsum/dd
0.0
0.5
1.0
1.5
0 25 50 75 100 125 150 175 200 225 250
PT(chgjet#1) or ET(jet#1) (GeV)
"Tra
nsv
erse
" P
Tsu
m D
ensi
ty (
GeV
/c)
CDF Preliminarydata uncorrectedtheory corrected
Charged Particles (||<1.0, PT>0.5 GeV/c) ChgJet#1 R = 0.7
JetClu Jet#1 (R = 0.7,|(jet)|<2)
PYTHIA Tune A 1.96 TeV
CDF Joint Physics Group June 27, 2003
Rick Field Page 9
““Transverse” Transverse” Charged Particle DensityCharged Particle Density
Shows the data on the average “transverse” charge particle density (||<1, PT>0.5 GeV) as a function of the transverse energy of the leading JetClu jet (R = 0.7, |(jet)| < 2) from Run 2.
JetClu Jet #1 Direction
“Toward”
“Transverse” “Transverse”
“Away”
Shows the generated prediction of PYTHIA Tune A before CDFSIM.
, compared with PYTHIA Tune A after CDFSIM.
"Transverse" Charged Particle Density: dN/dd
0.00
0.25
0.50
0.75
1.00
0 25 50 75 100 125 150 175 200 225 250
ET(jet#1) (GeV)"T
ran
sver
se"
Ch
arg
ed D
ensi
ty
CDF Preliminarydata uncorrected
Charged Particles (||<1.0, PT>0.5 GeV/c)
JetClu (R = 0.7, |(jet#1)| < 2)
"Transverse" Charged Particle Density: dN/dd
0.00
0.25
0.50
0.75
1.00
0 25 50 75 100 125 150 175 200 225 250
ET(jet#1) (GeV)"T
ran
sver
se"
Ch
arg
ed D
ensi
ty
PYTHIA Tune A
CDF Run 2 PreliminaryCDF Preliminary
data uncorrectedtheory corrected
Charged Particles (||<1.0, PT>0.5 GeV/c)
JetClu (R = 0.7, |(jet#1)| < 2)
"Transverse" Charged Particle Density: dN/dd
0.00
0.25
0.50
0.75
1.00
0 25 50 75 100 125 150 175 200 225 250
ET(jet#1) (GeV)"T
ran
sver
se"
Ch
arg
ed D
ensi
ty
PY Tune A Generated
PY Tune A Corrected
CDF Run 2 Preliminary
CDF Preliminarydata uncorrected
Charged Particles (||<1.0, PT>0.5 GeV/c)
JetClu (R = 0.7, |(jet#1)| < 2)
“Transverse” region as defined by the leading
“calorimeter jet”
CDFSIM/Generated: "Transverse" dN/dd
20%
30%
40%
50%
60%
70%
80%
90%
100%
0 25 50 75 100 125 150 175 200 225 250
ET(jet#1) (GeV)
CD
FS
IM/G
ener
ated
JetClu (R = 0.7, |(jet#1)| < 2)
Charged Particles (||<1.0, PT>0.5 GeV/c)
PYTHIA Tune A 1.96 TeV
Shows the ratio CDFSIM/Generated for PYTHIA Tune A.
Small correction (about 10%) independent of ET(jet#1)!
CDF Joint Physics Group June 27, 2003
Rick Field Page 10
The Leading The Leading “Charged Particle” Jet“Charged Particle” Jet
Shows the data on the average number of charged particles within the leading “charged particle jet” (||<1, PT>0.5 GeV, R = 0.7) as a function of the transverse momentum of the leading “charged particle jet” from Run 1.
Nchg(chgjet#1) versus PT(chgjet#1)
0
2
4
6
8
10
12
0 5 10 15 20 25 30 35 40 45 50
PT(charged jet#1) (GeV/c)
Ave
rave
Nch
g
CDF Run 1 Min-Bias
CDF Run 1 JET20
CDF Run 1 Datadata uncorrected
1.8 TeV ||<1.0 PT>0.5 GeV R = 0.7
Nchg(chgjet#1) versus PT(chgjet#1)
0
2
4
6
8
10
12
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
PT(charged jet#1) (GeV/c)
Ave
rave
Nch
g
CDF Run 1 Min-Bias
CDF Run 1 JET20
CDF Preliminarydata uncorrected
||<1.0 PT>0.5 GeV R = 0.7
Compares the Run 2 data (Min-Bias, JET20, JET50, JET70, JET100) with Run 1. The errors on the (uncorrected) Run 2 data include both statistical and correlated systematic uncertainties.
Nchg(chgjet#1) versus PT(chgjet#1)
0
2
4
6
8
10
12
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
PT(charged jet#1) (GeV/c)
Ave
rave
Nch
g
CDF Run 2
Nchg(chgjet#1) versus PT(chgjet#1)
0
2
4
6
8
10
12
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
PT(charged jet#1) (GeV/c)
Ave
rave
Nch
g
CDF Run 1 Min-Bias
CDF Run 1 JET20
CDF Run 2
CDF Preliminarydata uncorrected
||<1.0 PT>0.5 GeV/c R = 0.7
Nchg(chgjet#1) versus PT(chgjet#1)
0
2
4
6
8
10
12
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
PT(charged jet#1) (GeV/c)
Ave
rave
Nch
g
CDF Run 1 Min-Bias
CDF Run 1 JET20
CDF Run 2
PY Tune A
||<1.0 PT>0.5 GeV/c R = 0.7
CDF Preliminarydata uncorrectedtheory corrected
Excellent agreement between Run 1 and 2!
PYTHIA produces too many charged particles in the leading
“charged particle jet”!
CDF Joint Physics Group June 27, 2003
Rick Field Page 11
The Leading The Leading “Calorimeter” Jet“Calorimeter” Jet
Shows the Run 2 data on the average number of charged particles (||<1, PT>0.5 GeV, R = 0.7) within the leading “calorimeter jet” (JetClu R = 0.7, |(jet)|< 0.7) as a function of the transverse energy of the leading “calorimeter jet”.
Compares the number of charged particles within the leading “charged particle jet”, chgjet#1, with the number of charged particles within the leading “calorimeter jet” (JetClu R = 0.7), jet#1.
Nchg(jet#1) versus ET(jet#1)
0
2
4
6
8
10
12
0 25 50 75 100 125 150 175 200 225 250
ET(jet#1) (GeV)
Ave
rave
Nch
gCharged Particles (||<1.0, PT>0.5 GeV/c) JetClu R = 0.7 |(jet)| < 0.7
CDF Preliminarydata uncorrected
Nchg(jet#1) versus ET(jet#1)
0
2
4
6
8
10
12
0 25 50 75 100 125 150 175 200 225 250
ET(jet#1) (GeV)
Ave
rave
Nch
gCharged Particles (||<1.0, PT>0.5 GeV/c) JetClu R = 0.7 |(jet)| < 0.7
CDF Preliminarydata uncorrectedtheory corrected
PYTHIA Tune A 1.96 TeV
PYTHIA produces too many charged particles in the
leading “calorimeter jet”!
Nchg(jet#1) and Nchg(charged jet#1)
0
2
4
6
8
10
12
0 25 50 75 100 125 150 175 200 225 250
ET(jet#1) or PT(charged jet#1) (GeV)
Ave
rave
Nch
gCharged Particles (||<1.0, PT>0.5 GeV/c) JetClu R = 0.7 |(jet)| < 0.7
CDF Preliminarydata uncorrected
Nchg(jet#1)
Nchg(chgjet#1)
Nchg(jet#1) and Nchg(charged jet#1)
0
2
4
6
8
10
12
0 25 50 75 100 125 150 175 200 225 250
ET(jet#1) or PT(charged jet#1) (GeV)
Ave
rave
Nch
gCharged Particles (||<1.0, PT>0.5 GeV/c) JetClu R = 0.7 |(jet)| < 0.7
CDF Preliminarydata uncorrectedtheory corrected
PYTHIA Tune A 1.96 TeV
Nchg(jet#1)
Nchg(chgjet#1)
CDF Joint Physics Group June 27, 2003
Rick Field Page 12
The Leading “Calorimeter” JetThe Leading “Calorimeter” JetCharged Particle MultiplicityCharged Particle Multiplicity
Shows the Run 2 data on the average number of charged particles (||<1, PT>0.5 GeV, R = 0.7) within the leading “calorimeter jet” (JetClu R = 0.7, |(jet)|< 0.7) as a function of ET(jet#1) compared with PYTHIA Tune A after CDFSIM.
Shows the generated prediction of PYTHIA Tune A before CDFSIM.
Calorimeter Jet CDFSIM/Generated: Leading Jet Nchg
20%
30%
40%
50%
60%
70%
80%
90%
100%
0 25 50 75 100 125 150 175 200 225 250
ET(jet#1) (GeV)
CD
FS
IM/G
ener
ated
PYTHIA Tune A 1.96 TeV JetClu R = 0.7 |(jet)| < 0.7
Charged Particles (||<1.0, PT>0.5 GeV/c)
Shows the ratio CDFSIM/Generated for PYTHIA Tune A.
Correction becomes large for ET(jet#1) > 100 GeV and
depends on ET(jet#1)!
Shows “corrected” Run 2 data compared with PYTHIA Tune A (uncorrected).
Nchg(jet#1) versus ET(jet#1)
0
2
4
6
8
10
12
0 25 50 75 100 125 150 175 200 225 250
ET(jet#1) (GeV)A
vera
ve N
chg
Charged Particles (||<1.0, PT>0.5 GeV/c) JetClu R = 0.7 |(jet)| < 0.7
CDF Preliminarydata uncorrectedtheory corrected
PYTHIA Tune A 1.96 TeV
Nchg(jet#1) versus ET(jet#1)
0
2
4
6
8
10
12
14
0 25 50 75 100 125 150 175 200 225 250
ET(jet#1) (GeV)A
vera
ve N
chg
PY Tune A Generated
PY Tune A + CDFSIM
CDF Run 2 Uncorrected Charged Particles (||<1.0, PT>0.5 GeV/c)
JetClu R = 0.7 |(jet)| < 0.7
CDF Preliminarydata uncorrected
Nchg(jet#1) versus ET(jet#1)
0
2
4
6
8
10
12
14
0 25 50 75 100 125 150 175 200 225 250
ET(jet#1) (GeV)A
vera
ve N
chg
Charged Particles (||<1.0, PT>0.5 GeV/c)
JetClu R = 0.7 |(jet)| < 0.7
CDF Preliminarydata corrected
theory uncorrected
PYTHIA Tune A 1.96 TeV
Multiply data by the “unfolding function” (i.e. Generated/CDFSIM) determined from PYTHIA Tune A to get “corrected” data.
CDF Joint Physics Group June 27, 2003
Rick Field Page 13
The Leading “Calorimeter” JetThe Leading “Calorimeter” JetCharged PCharged PTT Distribution Distribution
Shows the transverse momentum distribution of charged particles (||<1) within the leading “charged particle jet” compared with PYTHIA Tune A. The plot shows dNchg/dz with z = PT/PT(chgjet#1) for the range 30 < PT(chgjet#1) < 70 GeV/c.
Shows the transverse momentum distribution of charged particles (||<1) within the leading “calorimeter jet” (JetClu, R = 0.7, |(jet)| < 0.7) compared with PYTHIA Tune A. The plot shows dNchg/dz with z = PT/ET(jet#1) for the range 30 < ET(jet#1) < 70 GeV.
PYTHIA produces too many “soft” charged particles within
the leading “jet”!
The integral of F(z) is the average number of charged particles within the
leading “charged particle jet”.
Leading Charged Particle Jet
0.1
1.0
10.0
100.0
0.0 0.2 0.4 0.6 0.8 1.0
z = PT/PT(chgjet#1)
F(z
) =
dN
/dz
CDF Preliminarydata uncorrectedtheory corrected
R = 0.7 30 < PT(chgjet#1) < 70 GeV
||<1.0 PT>0.5 GeV/c
PYTHIA Tune A 1.96 TeV
Leading Calorimeter Jet
1.0E-03
1.0E-02
1.0E-01
1.0E+00
1.0E+01
1.0E+02
0.0 0.2 0.4 0.6 0.8 1.0 1.2
z = PT/ET(Jet#1)
F(z
) =
dN
/dz
CDF Preliminarydata uncorrectedtheory corrected
JetClu R = 0.7 30 < ET(jet#1) < 70 GeV
Charged Particles (||<1.0, PT>0.5 GeV/c)
PYTHIA Tune A 1.96 TeV
PYTHIA produces too many “soft” charged particles within
the leading “jet”!
CDF Joint Physics Group June 27, 2003
Rick Field Page 14
The Leading “Calorimeter” JetThe Leading “Calorimeter” JetCharged PTCharged PTsumsum & PT & PTmaxmax Fraction Fraction
Shows average charged PTsum fraction, PTsum/ET(jet#1), and the average charged PTmax fraction, PTmax/ET(jet#1), within the leading “calorimeter jet” (JetClu, R = 0.7, |(jet)| < 0.7) compared with PYTHIA Tune A.
Shows distribution of the charged PTsum fraction, z = PTsum/ET(jet#1), and the distribution of charged PTmax fraction, z = PTmax/ET(jet#1), within the leading “calorimeter jet” (JetClu, R = 0.7, |(jet)| < 0.7) for the range 95 < ET(jet#1) < 130 GeV compared with PYTHIA Tune A.
Charged Fraction within the Leading Jet
0
2
4
6
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
z = PTmax/ET(jet#1) or PTsum/ET(jet#1)
(1/N
) d
N/d
z
CDF Preliminarydata uncorrectedtheory corrected
JetClu R = 0.7 95 < ET(jet#1) < 130 GeV
Charged Particles (||<1.0, PT>0.5 GeV/c)
PYTHIA Tune A 1.96 TeV
PTmax/ET(jet#1)
PTsum/ET(jet#1)
PYTHIA does okay on the charged PTmax fraction!PYTHIA does okay on the charged PTmax fraction!
But PYTHIA does not do well on the charged PTsum fraction!
But PYTHIA does not do as well on the charged PTsum fraction!
PTsum/ET(Jet#1) and PTmax/ET(jet#1)
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0 25 50 75 100 125 150 175 200 225 250
ET(jet#1) (GeV)
Ave
rag
e F
ract
ion
JetClu R = 0.7 |(jet)| < 0.7
CDF Preliminarydata uncorrectedtheory corrected
PYTHIA Tune A 1.96 TeV
Charged Particles (||<1.0, PT>0.5 GeV/c)
PTsum(chg)/ET(jet#1)
PTmax(chg)/ET(jet#1)
CDF Joint Physics Group June 27, 2003
Rick Field Page 15
The Leading “Calorimeter” JetThe Leading “Calorimeter” JetCharged PTCharged PTsumsum Fraction Fraction
Shows average charged PTsum fraction, PTsum/ET(jet#1), within the leading “calorimeter jet” (JetClu, R = 0.7, |(jet)| < 0.7) compared with PYTHIA Tune A after CDFSIM.
Calorimeter Jet
Shows the generated prediction of PYTHIA Tune A before CDFSIM.
CDFSIM/Generated: Leading Jet PTsum Fraction
20%
30%
40%
50%
60%
70%
80%
90%
100%
0 25 50 75 100 125 150 175 200 225 250
ET(jet#1) (GeV)
CD
FS
IM/G
ener
ated
PYTHIA Tune A 1.96 TeV
Charged Particles (||<1.0, PT>0.5 GeV/c)
JetClu R = 0.7 |(jet)| < 0.7
Shows the ratio CDFSIM/Generated for PYTHIA Tune A.
Very large correction that depends on ET(jet#1)!
Shows “corrected” Run 2 data compared with PYTHIA Tune A (uncorrected).
Leading Jet: Charged PTsum/ET(Jet#1)
0.2
0.3
0.4
0.5
0.6
0.7
0 25 50 75 100 125 150 175 200 225 250
ET(jet#1) (GeV)C
har
ged
PT
sum
/ET
(jet
#1)
JetClu R = 0.7 |(jet)| < 0.7
CDF Preliminarydata uncorrectedtheory corrected
PYTHIA Tune A 1.96 TeV
Charged Particles (||<1.0, PT>0.5 GeV/c)
Leading Jet: Charged PTsum/ET(jet#1)
0.2
0.3
0.4
0.5
0.6
0.7
0 25 50 75 100 125 150 175 200 225 250
ET(jet#1) (GeV)C
har
ged
PT
sum
/ET
(jet
#1)
PY Tune A Generated
PY Tune A + CDFSIM
CDF Run 2 Uncorrected
JetClu R = 0.7 |(jet)| < 0.7CDF Preliminarydata uncorrected
Charged Particles (||<1.0, PT>0.5 GeV/c)
Leading Jet: Charged PTsum/ET(jet#1)
0.2
0.3
0.4
0.5
0.6
0.7
0 25 50 75 100 125 150 175 200 225 250
ET(jet#1) (GeV)C
har
ged
PT
sum
/ET
(jet
#1)
JetClu R = 0.7 |(jet)| < 0.7CDF Preliminary
data correctedtheory uncorrected
Charged Particles (||<1.0, PT>0.5 GeV/c)
PYTHIA Tune A 1.96 TeV
Multiply data by the “unfolding function” (i.e. Generated/CDFSIM) determined from PYTHIA Tune A to get “corrected” data.
CDF Joint Physics Group June 27, 2003
Rick Field Page 16
Proton-AntiProtonProton-AntiProtonCollisionsCollisions
Draw an R = 0.7 cone around the leading calorimeter jet (JetClu, R = 0.7).
Proton AntiProton
Proton AntiProton
Jet Direction
R
ETjet
Proton AntiProton
Jet Direction
R
ETjet
PT
KT
Charged Particle
Look at charged particles within R = 0.7 of the leading calorimeter jet.
Momentum perpendicular to
the jet axis
Momentum perpendicular to
the beam axis
CDF Joint Physics Group June 27, 2003
Rick Field Page 17
The Leading “Calorimeter” JetThe Leading “Calorimeter” JetCharged KCharged KTT Distribution Distribution
Shows the average momentum perpendicular to the jet axis for charged particles (PT > 0.5 GeV/c, ||<1) within the leading “calorimeter jet” (JetClu, R = 0.7) compared with PYTHIA Tune A.
Shows the distribution of momentum perpendicular to the jet axis for charged particles within the leading “calorimeter jet” compared with PYTHIA Tune A. The plot shows dNchg/dKT for the range 30 < ET(jet#1) < 70 GeV and 95 < ET(jet#1) < 130 GeV.
Jet#1 <KT> versus ET(jet#1)
0.0
0.4
0.8
1.2
1.6
0 25 50 75 100 125 150 175 200 225 250
ET(jet#1) (GeV)
Av
erav
e K
T (
Ge
V/c
)
CDF Run 2
PY Tune A
JetClu R = 0.7 0.1 < |DET| < 0.7
CDF Preliminarydata uncorrectedtheory + CDFSIM
Perpendicular to Jet Axis
1.96 TeV
KT Distribution within Jet#1
1.0E-05
1.0E-04
1.0E-03
1.0E-02
1.0E-01
1.0E+00
1.0E+01
0 2 4 6 8 10 12 14 16 18 20
KT (GeV/c)
dN
/dK
T (
1/G
eV
/c)
Perpendicular to Jet Axis
CDF Preliminarydata uncorrectedtheory + CDFSIM
JetClu R = 0.7 0.1 < |DET| < 0.7
30 < ET(jet1) < 70 GeV
95 < ET(jet1) < 130 GeV
1.96 TeV
Increases as ET(jet#1) increases!
CDF Joint Physics Group June 27, 2003
Rick Field Page 18
Inclusive Inclusive Jet Cross SectionJet Cross Section
Shows the uncorrected inclusive “calorimeter jet” cross-section for (JetClu, R = 0.7, energy scale factor of 1.042) compared with PYTHIA Tune A (after CDFSIM).
Inclusive Jet Cross Section
1.0E-07
1.0E-06
1.0E-05
1.0E-04
1.0E-03
1.0E-02
1.0E-01
1.0E+00
1.0E+01
1.0E+02
1.0E+03
0 25 50 75 100 125 150 175 200 225 250
ET(jet) (GeV)
ds /
dE
T (m b
/Ge
V) CDF Run2 AllJets
PY Tune A
CDF Preliminarydata uncorrectedtheory + CDFSIM
JetClu R = 0.7 0.1 < |DET| < 0.7
1.96 TeV
Inclusive Jet Cross Section: Data/Theory
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
0 25 50 75 100 125 150 175 200 225 250
ET(jet) (GeV)
Ra
tio
: D
ata
/Th
eo
ry
JetClu R = 0.7 0.1 < |DET| < 0.7
CDF Preliminarydata uncorrected
PY Tune A + CDFSIM
1.96 TeV
Shows the ratio of the uncorrected inclusive “calorimeter jet” cross-section for (JetClu, R = 0.7, energy scale factor of 1.042) to PYTHIA Tune A (after CDFSIM).
Very similar to Frank Chlebana’s
“corrected” plots!
Data and theory are normalized to agree at this one point. This fixes the normalization for
all the other plots presented in this talk!
CDF Joint Physics Group June 27, 2003
Rick Field Page 19
Inclusive Cross-SectionInclusive Cross-Section“Correction Factors”“Correction Factors”
Shows PYTHIA Tune A + CDFSIM inclusive “calorimeter jet” cross-section for (JetClu, R = 0.7) compared with the “true” cross-section where “true” is the PTsum of all hadrons (partons) with PT > 0 in R = 0.7 cone around JetClu.
Inclusive Cross-Section: ds/dET
1.0E-07
1.0E-06
1.0E-05
1.0E-04
1.0E-03
1.0E-02
1.0E-01
1.0E+00
1.0E+01
1.0E+02
1.0E+03
0 25 50 75 100 125 150 175 200 225 250
ET (GeV)
ds /
dE
T (m b
/Ge
V)
ET(particles in R)
ET(partons in R)
ET(jetclu)
PYTHIA Tune A 1.96 TeV
0.1<|DET|<0.7
R = 0.7
Inclusive X-Sec Ratio: (PTsum in R=0.7)/ET(jetclu)
0.5
1.0
1.5
2.0
2.5
3.0
0 25 50 75 100 125 150 175 200 225 250
ET(jetclu) (GeV)
Cro
ss
-Se
cti
on
Ra
tio
PYTHIA Tune A 1.96 teV
0.1<|DET|<0.7
Particles
Partons
Measured
“True”
Correction factors!
ETsum(in R)/ET(jet#1) vs ET(jet#1)
0.8
0.9
1.0
1.1
1.2
1.3
0 25 50 75 100 125 150 175 200 225 250
ET(jet#1) (GeV)
ETs
um
(in
R)/
ET
(je
t)
PYTHIA Tune A 1.96 TeV
0.1<|DET|<0.7
Particles
Partons
JetClu R = 0.7
“True”
CDF Joint Physics Group June 27, 2003
Rick Field Page 20
Jet Cross SectionsJet Cross Sections
Shows the Run 2 uncorrected inclusive “calorimeter jet” cross-section and the leading “calorimeter jet” cross-section (JetClu, R = 0.7, energy scale factor of 1.042).
Shows the ratio of the leading jet cross section to the inclusive jet cross-section for (JetClu, R = 0.7, energy scale factor of 1.042) compared with PYTHIA Tune A (after CDFSIM).
Jet Cross Sections
1.0E-07
1.0E-06
1.0E-05
1.0E-04
1.0E-03
1.0E-02
1.0E-01
1.0E+00
1.0E+01
1.0E+02
1.0E+03
0 25 50 75 100 125 150 175 200 225 250
ET(jet) (GeV)
ds /
dE
T (m b
/Ge
V) CDF Run2 AllJets
CDF Run2 Jet1
CDF Preliminarydata uncorrected
JetClu R = 0.7 0.1 < |DET| < 0.7
1.96 TeV
Jet Cross-Section Ratio: Jet#1/AllJets
0.5
0.6
0.7
0.8
0.9
1.0
0 25 50 75 100 125 150 175 200 225 250
ET(jet) (GeV)
Jet#
1/A
llJet
s
CDF Run 2
PY Tune A
JetClu R = 0.7 0.1 < |DET| < 0.7
CDF Preliminarydata uncorrectedtheory + CDFSIM
1.96 TeV
Measures how much cross-section comes
from >1 jet!
CDF Joint Physics Group June 27, 2003
Rick Field Page 21
Jet Cross SectionsJet Cross Sections
Shows the uncorrected inclusive jet cross-section for (JetClu, R = 0.7, energy scale factor of 1.042) compared with PYTHIA Tune A (after CDFSIM).
Shows the ratio of the uncorrected inclusive jet cross-section for (JetClu, R = 0.7, energy scale factor of 1.042) to PYTHIA Tune A (after CDFSIM).
Jet Cross Sections
1.0E-09
1.0E-08
1.0E-07
1.0E-06
1.0E-05
1.0E-04
1.0E-03
1.0E-02
1.0E-01
1.0E+00
1.0E+01
1.0E+02
1.0E+03
0 25 50 75 100 125 150 175 200 225 250
ET(jet) (GeV)
ds /
dE
T
(mb
/Ge
V)
CDF Preliminarydata uncorrectedtheory + CDFSIM
JetClu R = 0.7 0.1 < |DET| < 0.7
Jet#1
Jet#2Jet#3
1.96 TeV
Jet Cross-Sections: Data/Theory
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
0 25 50 75 100 125 150 175 200 225 250
ET(jet) (GeV)
Ra
tio
: D
ata
/Th
eo
ry
Jet#1
Jet#2
Jet#3
JetClu R = 0.7 0.1 < |DET| < 0.7
CDF Preliminarydata uncorrected
PY Tune A + CDFSIM
1.96 TeV
PThat/ET(jet#1) vs ET(jet#1)
0.7
0.8
0.9
1.0
1.1
1.2
1.3
0 25 50 75 100 125 150 175 200 225 250
ET(jet#1) (GeV)
PT
ha
t/E
T(j
et#
1)
PYTHIA Tune A 1.96 TeV
0.1<|DET|<0.7
JetClu R = 0.7
Tansverse momentum of the hard 2-to-2 parton-parton collision!
CDF Joint Physics Group June 27, 2003
Rick Field Page 22
Leading “Charged Particle Jet” Leading “Charged Particle Jet” Cross SectionCross Section
Shows the uncorrected leading “charged particle jet” cross-section for (PT > 0.5 GeV/c, ||<1) compared with PYTHIA Tune A (after CDFSIM).
Shows the ratio of the uncorrected leading “charged particle jet” cross-section for (PT > 0.5 GeV/c, ||<1) to PYTHIA Tune A (after CDFSIM).
Leading ChgJet Cross Section
1.0E-06
1.0E-05
1.0E-04
1.0E-03
1.0E-02
1.0E-01
1.0E+00
1.0E+01
1.0E+02
1.0E+03
1.0E+04
0 25 50 75 100 125 150
PT(charged jet#1) (GeV/c)
ds /
dP
T (m b
/Ge
V) PY Tune A
CDF Run2
CDF Preliminarydata uncorrectedtheory corrected
1.96 TeV ||<1.0 PT>0.5 GeV R = 0.7
Leading ChgJet Cross Section: Data/Theory
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
0 25 50 75 100 125 150
PT(charged jet#1) (GeV)
Ra
tio
: D
ata
/Th
eo
ry
PT > 0.5 GeV/c || < 0.7 R = 0.7
CDF Preliminarydata uncorrected
PY Tune A + CDFSIM
1.96 TeV
Jet Cross-Sections: Data/Theory
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
0 25 50 75 100 125 150 175 200 225 250
ET(jet#1) or PT(charged jet#1) (GeV)
Ra
tio
: D
ata
/Th
eo
ry
Charged Particle Jet#1
Calorimeter Jet#1
CDF Preliminarydata uncorrected
PY Tune A + CDFSIM
Compares data/theory for the leading charged particle jet and the
leading calorimeter jet!
CDF Joint Physics Group June 27, 2003
Rick Field Page 23
Summary & ConclusionsSummary & Conclusions
PYTHIA Tune A
PYTHIA Tune A does a good job of describing the “underlying event” in the Run 2 data as defined by “charged particle jets” and as defined by “calorimeter jets”. HERWIG Run 2 comparisons will be coming soon!
PYTHIA Tune A does a fairly good job (although not perfect) describing the properties of the “calorimeter jets” in Run 2 (in the central region!).
I am hoping we can use the QCD Monte-Carlo models (PYTHIA & HERWIG) to correct the data from measured to “true” by constructing “correction factors” for every observable of interest.
Proton AntiProton
PT(hard)
Outgoing Parton
Outgoing Parton
Underlying Event Underlying Event
Initial-State Radiation
Final-State Radiation
This is a different method from the “jet energy corrections” used in Run 1!