b physics: qcd monte carlo model predictionsrfield/cdf/bplots_feb25.pdf · b physics: qcd monte...

Rick Field & Keith Ellis Run 2 Workshop – February 2000 of 28

B Physics: QCD Monte Carlo Model Predictions

Rick Field - University of Florida

and Keith Ellis - Fermilab

Goals: • Compare the LO parton level predictions of Herwig, Isajet,

and Pythia with the NLO MRSR2 predictions. • Compare the LO parton level predictions with the LO

hadron level predictions (Herwig, Isajet, Pythia). • Compare the LO hadron level predictions of Herwig, Isajet,

and Pythia. Outline: • Integrated Cross Sections (parton level) • Transverse Momentum Distributions (parton level) • Pseudo-Rapidity & Rapidity Distributions (parton level) • Integrated Cross Sections (hadron level) • Transverse Momentum Distributions (hadron level) • PT Distributions Parton/Hadron (fragmentation) • Strange Quark Production fs/(fu+fd) (fragmentation) • Y and ηη Distributions Hadron versus Parton • Comparisons between 1.8 TeV and 2.0 TeV • Azimuthal ∆φ∆φ Correlations Hadron and Parton • PT Correlations Hadron and Parton (PT1-PT2) • Pseudo-Rapidity Correlations: dσσ/dηη1dηη2 & R(ηη1,ηη2)

QCD Monte Carlo Models (default parameters):Herwig 5.9 (DO1.1, ΛΛ = 0.18 GeV)Isajet 7.32 (CTEQ3L, ΛΛ = 0.20 GeV)Pythia 6.115 (GRV94LO, ΛΛ = 0.23 GeV)

Pythia 6.115 (CTEQ3L, ΛΛ = 0.18 GeV)

Run 2 Workshop on QCD CDF B-Group Meeting Run 2 Workshop of B Physics

63 Plots!

This Talk

http://www.phys.ufl.edu/~rfield/cdf/Bplots_feb25.pdf


B Physics: Cross Sections Parton Level: Integrated b-quark Cross Section for PT > PTmin

Integrated b-quark Cross Section for PT > PTmin

1.0E-03

1.0E-02

1.0E-01

1.0E+00

1.0E+01

1.0E+02

5 10 15 20 25 30 35 40

PTmin (GeV)

MRSR2 b-quark

Herwig b-quark

Isajet b-quark

PythiaC3L b-quark

Pythia b-quark

1.8 TeVall y

σσ µµb

Plot shows σσ(PT>PTmin) (in µµb) for b-quarks at 1.8 TeV (all Y). Parton Level: Integrated b-quark Cross Section for PT > PTmin


1.0E-03

1.0E-02

1.0E-01

1.0E+00

1.0E+01

1.0E+02

5 10 15 20 25 30 35 40

PTmin (GeV)

MRSR2 b-quark

Herwig b-quark times 2

Isajet b-quark times 2

Pythia b-quark times 2

1.8 TeVall y

σσ µµb

Plot shows σσ(PT>PTmin) (in µµb) for b-quarks at 1.8 TeV (all Y). Herwig, Isajet, and Pythia have been increased by a factor of two.


B Physics: Cross Sections Parton Level: Ratio MRSR2/Monte-Carlos


1

2

3

4

5 10 15 20 25 30 35 40

PTmin (GeV)

MRSR2/Herwig

MRSR2/Isajet

MRSR2/PythiaC3L

MRSR2/Pythia

1.8 TeVall y

Plot shows the ratio of σσ(PT>PTmin) for b-quarks at 1.8 TeV (all Y) from MRSR2 to Herwig, Isajet, Pythia, and PythiaC3L.

Parton Level: Integrated b-quark Cross Section for PT > PTmin


1.0E-03

1.0E-02

1.0E-01

1.0E+00

1.0E+01

5 10 15 20 25 30 35 40

PTmin (GeV)

MRSR2 b-quark

Herwig b-quark

Isajet b-quark

Pythia b-quark

D0 Data

CDF Data

σσ µµb

1.8 TeV|y| < 1

Plot shows σσ(PT>PTmin) (in µµb) for b-quarks at 1.8 TeV (|Y|<1).


B Physics: Cross Sections Parton Level: Integrated b-quark Cross Section for PT > PTmin


1.0E-03

1.0E-02

1.0E-01

1.0E+00

1.0E+01

1.0E+02

5 10 15 20 25 30 35 40

PTmin (GeV)

MRSR2 b-quark times 2

Herwig b-quark times 4

Isajet b-quark times 4

Pythia b-quark times 4

D0 Data

CDF Data

σσ µµb

1.8 TeV|y| < 1

Plot shows σσ(PT>PTmin) (in µµb) for b-quarks at 1.8 TeV (|Y|<1). MRSR2 has been increased by a factor of two and Herwig, Isajet, and Pythia have been increased by a factor of four.

Parton Level: Ratio MRSR2/Monte-Carlos


1

2

3

4

5 10 15 20 25 30 35 40

PTmin (GeV)

MRSR2/Herwig

MRSR2/Isajet

MRSR2/Pythia

1.8 TeV|y| < 1

Plot shows the ratio of σσ(PT>PTmin) for b-quarks at 1.8 TeV (|Y| < 1) from MRSR2 to Herwig, Isajet, and Pythia.


B Physics: Cross Sections Parton Level: Fraction |Y| < 1 of the b-quark Cross Section

Fraction |y|<1 of the Integrated b-quark Cross Section

30%

40%

50%

60%

70%

5 10 15 20 25 30 35 40

PTmin (GeV)

MRSR2 b-quark Herwig b-quark Isajet b-quark Pythia b-quark

1.8 TeV

Plot shows the fraction |Y| < 1 of the b-quark integrated cross section (PT < PTmin). Parton Level: Fraction |ηη| < 1 of the b-quark Cross Section

Fraction |eta|<1 of the Integrated b-quark Cross Section

30%

40%

50%

60%

70%

5 10 15 20 25 30 35 40

PTmin (GeV)


1.8 TeV

Plot shows the fraction |ηη| < 1 of the b-quark integrated cross section (PT < PTmin).


B Physics: PT Distributions Parton Level: Transverse Momentum Distribution (|ηη| < 1)

Transverse Momentum Distribution dσσ/dPT

1.0E-05

1.0E-04

1.0E-03

1.0E-02

1.0E-01

1.0E+00

1.0E+01

5 10 15 20 25 30 35 40 45 50

PT (GeV)

MRSR2 b-quark

Herwig b-quark

Isajet b-quark

Pythia b-quark

µµb/GeV

1.8 TeV|eta| < 1

Plot shows dσσ/dPT (in µµb/GeV) for b-quarks at 1.8 TeV (|ηη|<1). Parton Level: Transverse Momentum Distribution (|ηη| < 1)

Transverse Momentum Distribution (b-quark)

1

2

3

4

5 10 15 20 25 30 35 40 45 50

PTmin (GeV)

MRSR2/Isajet MRSR2/Herwig MRSR2/Pythia

1.8 TeV|eta| < 1

Plot shows the ratio of dσσ/dPT for b-quarks at 1.8 TeV (|ηη| < 1) from MRSR2 to Herwig, Isajet, and Pythia.


B Physics: Pseudo-Rapidity Distributions Parton Level: Pseudo-Rapidity Distributions (PT > 5 GeV)

Pseudo-Rapidity Distribution

0

1

2

3

4

-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6

Pseudo-Rapidity ηη

MRSR2 b-quark Herwig b-quark Isajet b-quark PythiaC3L b-quark Pythia b-quark

dσσ/dηη (µµb)

1.8 TeVPT > 5 GeV

Plot shows dσσ/dηη (in µµb) for b-quarks at 1.8 TeV (PT > 5 GeV).

Parton Level: Pseudo-Rapidity Distributions (PT > 5 GeV)

Pseudo-Rapidity Distribution (normalized to 1)

0.00

0.05

0.10

0.15

0.20

-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6


MRSR2 b-quark Herwig b-quark Isajet b-quark PythiaC3L b-quark Pythia b-quark

(1/N)dN/dηη

1.8 TeVPT > 5 GeV

Plot shows (1/N)dN/dηη (normalized to 1) for b-quarks at 1.8 TeV (PT > 5 GeV).


B Physics: Rapidity Distributions Parton Level: Rapidity Distributions (PT > 5 GeV)

Rapidity Distribution

0

1

2

3

4

-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6

Rapidity Y


1.8 TeVPT > 5 GeV

dσσ/dY (µµb)

Plot shows dσσ/dY (in µµb) for b-quarks at 1.8 TeV (PT > 5 GeV). Parton Level: Rapidity Distributions (PT > 5 GeV)

Rapidity Distribution (normalized to 1)

0.00

0.05

0.10

0.15

0.20

0.25

-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6

Rapidity Y


1.8 TeVPT > 5 GeV

(1/N)dN/dY

Plot shows (1/N)dN/dY (normalized to 1) for b-quarks at 1.8 TeV (PT > 5 GeV).


B Physics: Cross Sections Hadron Level: Integrated B-quark Cross Section for PT > PTmin

Integrated Cross Section for PT > PTmin

1.0E-04

1.0E-03

1.0E-02

1.0E-01

1.0E+00

1.0E+01

5 10 15 20 25 30 35 40 45

PTmin (GeV)

Pythia b-quark

Pythia B-mesons

Isajet b-quark

Isajet B-mesons

Herwig b-quark

Herwig B-mesons

σσ µµb

B-mesons = (B+,B0,Bs0)

1.8 TeV|eta| < 1

B-mesons

b-quark

Plot shows σσ(PT>PTmin) (in µµb) for B-mesons (B+,B0,Bs

0) and b-quarks at 1.8 TeV

(|ηη| < 1). Hadron Level: Integrated B-quark Cross Section for PT > PTmin

Integrated Cross Section for PT > PTmin

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

5 10 15 20 25 30 35 40 45

PTmin (GeV)

σσ µµb

Isajet at 1.8 TeV|eta| < 1

B-mesons fromtop quarks

B-mesons frombottom quarks


Plot shows σσ(PT>PTmin) (in µµb) for B-mesons (B+,B0,Bs

0) from b and t-quarks 1.8

TeV (|ηη| < 1).


B Physics: PT Distributions Parton & Hadron Level: Transverse Momentum Distribution (|ηη| < 1)

Transverse Momentum Distribution dσσ/dPT

1.0E-05

1.0E-04

1.0E-03

1.0E-02

1.0E-01

1.0E+00

5 10 15 20 25 30 35 40 45 50

PT (GeV)

Pythia b-quark

Pythia B-mesons

Isajet b-quark

Isajet B-mesons

Herwig b-quark

Herwig B-mesons

1.8 TeV|eta| < 1


µµb/GeV

B-mesons

b-quark

Plot shows dσσ/dPT (in µµb/GeV) for B-mesons (B+,B0,Bs

0) and for the b-quark at 1.8

TeV (|ηη|<1). Hadron/Parton Level: Transverse Momentum Distribution (|ηη| < 1)

(B-meson)/(b-quark) Ratio versus PT

0%

20%

40%

60%

80%

100%

5 10 15 20 25 30 35 40 45 50

PT (GeV)

Pythia Herw ig Isajet


1.8 TeV|eta| < 1

Plot shows the ratio of dσσ/dPT (|ηη| < 1) for B-mesons (B+,B0,Bs

0) to b-quark at 1.8 TeV.


B Physics: PT Distributions Hadron Level: B+ Meson Transverse Momentum Distribution (|Y| < 1)

B+ Meson Transverse Momentum Distribution

1.0E-04

1.0E-03

1.0E-02

1.0E-01

1.0E+00

5 10 15 20 25 30 35 40

PT (GeV)

Herwig B+ meson Isajet B+ meson Pythia B+ meson CDF Data CDF Data CDF Data

µµb/GeV

1.8 TeV|Y| < 1

Plot shows dσσ/dPT (in µµb/GeV) for B+ mesons at 1.8 TeV (|Y| < 1). Hadron Level: B+ Meson Transverse Momentum Distribution (|Y| < 1)

B+ Meson Transverse Momentum Distribution

1.0E-04

1.0E-03

1.0E-02

1.0E-01

1.0E+00

5 10 15 20 25 30 35 40

PT (GeV)

Herwig times 4 Isajet times 4 Pythia times 4 CDF Data CDF Data CDF Data

µµb/GeV

1.8 TeV|Y| < 1

Plot shows dσσ/dPT (in µµb/GeV) for B+ mesons at 1.8 TeV (|Y| < 1). The QCD Monte-Carlo predictions have been increased by a factor of four.


B Physics: Fragmentation

CDF Run I Old FF fu 0.408+/-0.068 0.4 fd 0.344+/-0.039 0.4 fs 0.159+/-0.026 0.2 fbaryon 0.089+/-0.029 0.0 fs/(fu+fd) 0.213+/-0.068 0.25

Hadron Level: fs/(fu+fd) Ration versus PT (|ηη| < 1)

fs/(fu+fd) Ratio versus PT

0%

10%

20%

30%

40%

5 10 15 20 25 30

PT (GeV)

Herwig Isajet Pythia CDF Data

1.8 TeV|eta| < 1

Old FF

Plot shows the ratio fs/(fu+fd) at 1.8 TeV (|ηη| < 1), where fs = dσσ/dPT(Bs

0), fu =

dσσ/dPT(B+), and fd = dσσ/dPT(B0).

uK+

s

sbarfs

uππ+

d

dbarfd

bbarB+

ubar

ufu

bbarBs0

sbar

sfs


B Physics: Y and ηη Distributions Parton & Hadron Level: Pseudo-Rapidity Distribution

Pseudo-Rapidity Distribution (normalized to 1)

0.00

0.05

0.10

0.15

0.20

0.25

-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6


Isajet b-quark Isajet B-mesons Isajet b-quark Isajet B-mesons

(1/N)dN/dηη

Isajet at 1.8 TeV B-mesons = (B+,B0,Bs0)

PT > 5 GeV

PT > 10 GeV

Plot shows (1/N)dN/dηη (normalized to 1) for B-mesons (B+,B0,Bs

0) and for the b-quark at 1.8 TeV (PT > 5 GeV and PT > 10 GeV). Parton & Hadron Level: Rapidity Distribution


0.00

0.05

0.10

0.15

0.20

0.25

-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6

Rapidity Y


(1/N)dN/dY

Isajet at 1.8 TeV B-mesons = (B+,B0,Bs0)

PT > 5 GeV

PT > 10 GeV

Plot shows (1/N)dN/dY (normalized to 1) for B-mesons (B+,B0,Bs

0) and for the b-quark at 1.8 TeV (PT > 5 GeV and PT > 10 GeV).




0.00

0.05

0.10

0.15

0.20

0.25

-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6


Herwig b-quark Herwig B-mesons Herwig b-quark Herwig B-mesons

Herwig at 1.8 TeV

(1/N)dN/dηη


PT > 5 GeV

PT > 10 GeV




0.00

0.05

0.10

0.15

0.20

0.25

-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6

Rapidity Y

Herwig b-quark Herwig b-quark Herwig B-mesons Herwig B-mesons

Herwig at 1.8 TeV

(1/N)dN/dY


PT > 5 GeV

PT > 10 GeV






0.00

0.05

0.10

0.15

0.20

0.25

-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6


Pythia b-quark Pythia B-mesons Pythia b-quark Pythia B-mesons

Pythia at 1.8 TeV

(1/N)dN/dηη


PT > 5 GeV

PT > 10 GeV




0.00

0.05

0.10

0.15

0.20

0.25

-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6

Rapidity Y

Pythia b-quark Pythia B-mesons Pythia b-quark Pythia B-mesons

Pythia at 1.8 TeV

(1/N)dN/dY


PT > 5 GeV

PT > 10 GeV




B Physics: Azimuthal Correlations

Beam Axis

∆φ∆φ

b-quark or B-mesons

bbar-quark orBbar-mesons

PT1PT2

Parton Level: Azimuthal ∆φ∆φ Distribution

Azimuthal ∆φ ∆φ Distribution (normalized to 1)

0.000

0.010

0.020

0.030

0.040

90 100 110 120 130 140 150 160 170 180

∆φ∆φ = |φφ2-φφ1| (degrees)


1.8 TeV1 = b-quark 2 = bbar-quark

|eta1| < 1 |eta2| < 1PT1 > 5 GeV

(1/N)dN/d∆φ∆φ

Plot shows (1/N)dN/d∆φ∆φ (normalized to 1), where ∆φ∆φ = |φφ2-φφ1| for 1 = b-quark and 2

= bbar-quark at 1.8 TeV with |ηη1| < 1, |ηη2| < 1, and PT1 > 5 GeV.

Hadron Level: Azimuthal ∆φ∆φ Distribution

Azimuthal ∆ φ ∆ φ Distribution (normalized to 1)

0.000

0.010

0.020

0.030

0.040

90 100 110 120 130 140 150 160 170 180


Herwig B-meson Isajet B-mesons Pythia B-meson


1.8 TeV1 = B-meson 2 = Bbar-meson

|eta1| < 1 |eta2| < 1PT1 > 5 GeV

(1/N)dN/d∆φ∆φ

Plot shows (1/N)dN/d∆φ∆φ (normalized to 1), where ∆φ∆φ = |φφ2-φφ1| for 1 = B-mesons

(B+,B0,Bs0) and 2 = Bbar-mesons at 1.8 TeV with |ηη1| < 1, |ηη2| < 1, and PT1 > 5 GeV.

Measures intrensic PT, gluon radiation, fragmentation.


B Physics: Azimuthal Correlations Parton & Hadron Level: Azimuthal ∆φ∆φ Distribution


0.000

0.010

0.020

0.030

90 100 110 120 130 140 150 160 170 180


Herwig b-quark Herwig B-meson

1.8 TeV1 = b-quark or B-meson

2 = bbar-quark or Bbar-meson|eta1| < 1 |eta2| < 1

PT1 > 5 GeV

(1/N)dN/d∆φ∆φ



= bbar-quark and for 1 = B-mesons (B+,B0,Bs0) and 2 = Bbar-mesons at 1.8 TeV

with |ηη1| < 1, |ηη2| < 1, and PT1 > 5 GeV. Parton & Hadron Level: Azimuthal ∆φ∆φ Distribution


0.000

0.010

0.020

0.030

0.040

90 100 110 120 130 140 150 160 170 180


Pythia b-quark Pythia B-meson

1.8 TeV1 = b-quark or B-meson

2 = bbar-quark or Bbar-meson|eta1| < 1 |eta2| < 1

PT1 > 5 GeV

(1/N)dN/d∆φ∆φ



= bbar-quark and for 1 = B-mesons (B+,B0,Bs0) and 2 = Bbar-mesons at 1.8 TeV

with |ηη1| < 1, |ηη2| < 1, and PT1 > 5 GeV.


B Physics: Azimuthal Correlations Hadron Level: Azimuthal ∆φ∆φ Distribution


0.000

0.010

0.020

0.030

0.040

0 20 40 60 80 100 120 140 160 180


Herwig B-meson Isajet B-meson Pythia B-meson PythiaC3L B-meson



|eta1| < 1 |eta2| < 1PT1 > 5 GeV

(1/N)dN/d∆φ∆φ


(B+,B0,Bs0) and 2 = Bbar-mesons at 1.8 TeV with |ηη1| < 1, |ηη2| < 1, and PT1 > 5 GeV.

Hadron Level: Azimuthal ∆φ∆φ Distribution


0.000

0.020

0.040

0.060

90 100 110 120 130 140 150 160 170 180


1.8 TeV1 = B-meson

2 = Bbar-meson|eta1| < 1 |eta2| < 1

(1/N)dN/d∆φ∆φ


PT1 > 5 GeV

PT1 > 10 GeV

PT1 > 25 GeVHerwig B-mesons


(B+,B0,Bs0) and 2 = Bbar-mesons at 1.8 TeV with |ηη1| < 1, |ηη2| < 1, and PT1 > 5, 10,

and 25 GeV.


B Physics: Azimuthal Correlations Hadron Level: Azimuthal ∆φ∆φ Distribution


0.000

0.020

0.040

0.060

90 100 110 120 130 140 150 160 170 180


1.8 TeV1 = B-meson

2 = Bbar-meson|eta1| < 1 |eta2| < 1

(1/N)dN/d∆φ∆φ


PT1 > 5 GeV

PT1 > 10 GeV

PT > 25 GeV

Pythia B-mesons


(B+,B0,Bs0) and 2 = Bbar-mesons at 1.8 TeV with |ηη1| < 1, |ηη2| < 1, and PT1 > 5, 10,

and 25 GeV. Hadron Level: Azimuthal ∆φ∆φ Distribution


0.000

0.010

0.020

0.030

0.040

0.050

90 100 110 120 130 140 150 160 170 180


Herwig B-meson Isajet B-mesons Pythia B-meson


|eta1| < 1 |eta2| < 1PT1 > 10 GeV


(1/N)dN/d∆φ∆φ


(B+,B0,Bs0) and 2 = Bbar-mesons at 1.8 TeV with |ηη1| < 1, |ηη2| < 1, and PT1 > 10

GeV.


B Physics: PT Correlations

Beam Axis

∆φ∆φ

b-quark or B-mesons

bbar-quark orBbar-mesons

PT1PT2

Parton Level: Transverse Momentum Correlations

Transverse Momentum Correlations dσσ/d∆∆PT

1.0E-04

1.0E-03

1.0E-02

1.0E-01

1.0E+00

-20 -15 -10 -5 0 5 10 15 20

∆∆PT = PT1 - PT2 (G e V )

Herwig b-quark Isajet b-quark Pythia b-quark

1.8 TeV1 = b quark 2 = bbar quark

|eta1|< 1 |eta2|<1 |phi1-phi2|>90 degPT2 > 5 GeV

dσσ/d∆∆PT (µµb/Gev)

Plot shows dσσ/d∆∆PT (µµb/GeV), where ∆∆PT = PT1-PT2 for 1 = b-quark and 2 =

bbar-quark at 1.8 TeV with |ηη1| < 1, |ηη2| < 1, |φφ1-φφ2| > 90o, and PT2 > 5 GeV.

Parton Level: Transverse Momentum Correlations

PT Correlations (normalized to 1)

0.00

0.05

0.10

0.15

0.20

-15 -10 -5 0 5 10 15

∆∆PT = PT1 - PT2 (GeV)

Herwig b-quark Isajet b-quark Pythia b-quark

(1/N)dN/d∆∆PT

1.8 TeV1 = b quark 2 = bbar quark


Plot shows (1/N)dN/d∆∆PT (1/GeV), where ∆∆PT = PT1-PT2 for 1 = b-quark and 2 =

bbar-quark at 1.8 TeV with |ηη1| < 1, |ηη2| < 1, |φφ1-φφ2| > 90o, and PT2 > 5 GeV.


B Physics: PT Correlations Hadron Level: Transverse Momentum Correlations


0.00

0.05

0.10

0.15

0.20

-15 -10 -5 0 5 10 15


Herwig B-mesons Isajet B-mesons Pythia B-mesons

1.8 TeV1 = B-mesons 2 = Bbar-mesons


(1/N)dN/d∆∆PT


Plot shows (1/N)dN/d∆∆PT (1/GeV), where ∆∆PT = PT1-PT2 for 1 = B-mesons

(B+,B0,Bs0) and 2 = Bbar-mesons at 1.8 TeV with |ηη1| < 1, |ηη2| < 1, |φφ1-φφ2| > 90o, and

PT2 > 5 GeV.

Parton & Hadron Level: Transverse Momentum Correlations


0.00

0.05

0.10

0.15

-15 -10 -5 0 5 10 15


Herwig b-quark Herwig B-mesons

(1/N)dN/d∆∆PT

1.8 TeV1 = b-quark or B-mesons

2 = bbar-quark or Bbar-mesons|eta1|< 1 |eta2|<1 |phi1-phi2|>90 deg

PT2 > 5 GeV



bbar-quark and for 1 = B-mesons (B+,B0,Bs0) and 2 = Bbar-mesons at 1.8 TeV with

|ηη1| < 1, |ηη2| < 1, |φφ1-φφ2| > 90o, and PT2 > 5 GeV.

Measures intrensic PT, gluon radiation, and fragmentation.


B Physics: PT Correlations Parton & Hadron Level: Transverse Momentum Correlations


0.00

0.05

0.10

0.15

-15 -10 -5 0 5 10 15


Herwig b-quark Herwig B-mesons Herwig b-quark Herwig B-mesons

(1/N)dN/d∆∆PT




PT2 > 10 GeV

PT2 > 5 GeV



|ηη1| < 1, |ηη2| < 1, |φφ1-φφ2| > 90o, and PT2 > 5 and 10 GeV.

Parton & Hadron Level: Transverse Momentum Correlations


0.00

0.05

0.10

0.15

0.20

-15.0 -10.0 -5.0 0.0 5.0 10.0 15.0



(1/N)dN/d∆∆PT (1/Gev)




PT2 > 10 GeV

PT2 > 5 GeV

Plot shows (1/N)dN/d∆∆PT (1//GeV), where ∆∆PT = PT1-PT2 for 1 = b-quark and 2 =


|ηη1| < 1, |ηη2| < 1, |φφ1-φφ2| > 90o, and PT2 > 5 and 10 GeV.


B Physics: PT Correlations Hadron Level: Transverse Momentum Correlations


0.00

0.05

0.10

0.15

0.20

-15 -10 -5 0 5 10 15


Herwig B-mesons Isajet B-mesons Pythia B-mesons PythiaC3L B-mesons




(1/N)dN/d∆∆PT



PT2 > 5 GeV.

Hadron Level: Transverse Momentum Correlations


0.00

0.05

0.10

0.15

-15 -10 -5 0 5 10 15


Herwig B-mesons Isajet B-mesons Pythia B-mesons PythiaC3L B-mesons




(1/N)dN/d∆∆PT



PT2 > 10 GeV.


B Physics: Pseudo-Rapidity Correlations Correlation Functions:

212

2121

11),(

ησ

ησ

σηησ

σηη

d

d

d

d

dd

dC −=

“Normalized” Correlation Functions:

−=

212

212

2121

111),(

ησ

ησ

σησ

ησ

σηησ

σηη

dd

dd

dd

dd

ddd

R

“Integrated” (a < ηη2 < b) Normalized Correlation Functions:

∫∫

−=

b

a

b

a

ddd

dd

ddd

dd

ddd

R 221

2221

221

1

111)( η

ησ

ησ

ση

ησ

ησ

σηησ

ση

Hadron Level: Pseudo-Rapidity Correlations (|ηη2| < 0.5)

Pseudo-Rapidity Correlations dσσ/dηη1dηη2

0.000

0.005

0.010

0.015

0.020

-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6

Pseudo-Rapidity ηη11

Herwig B-mesons Isajet B-mesons PythiaC3L B-mesons Pythia B-mesons

(1/σσ)dσσ/dηη1dηη2

1.8 TeV |eta2| < 0.51 = B-mesons 2 =Bbar-mesons

|PT1| < 5 GeV |PT2| < 5 GeV|phi1-phi2|>90 deg

eta2

Plot shows (1/σσ)dσσ/dηη1dηη2 versus ηη1, for 1 = B-mesons (B+,B0,Bs

0) and 2 = Bbar-

mesons at 1.8 TeV with |ηη2| < 0.5, |φφ1-φφ2| > 90o, PT1 > 5 GeV, and PT2 > 5 GeV.

Double-Differential Cross Section


B Physics: Pseudo-Rapidity Correlations Hadron Level: Pseudo-Rapidity Correlations (1 < |ηη2| < 2)


0.000

0.005

0.010

0.015

0.020

-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6




1.8 TeV 1<|eta2|<21 = B-mesons 2 = Bbar-mesons

|PT1|< 5 GeV |PT2|< 5 GeV|phi1-phi2|>90 deg

eta2


0) and 2 = Bbar-

mesons at 1.8 TeV with 1 < |ηη2| < 2, |φφ1-φφ2| > 90o, PT1 > 5 GeV, and PT2 > 5 GeV.

Hadron Level: Pseudo-Rapidity Correlations (1 < |ηη2| < 2)

Pseudo-Rapidity Correlations dσσ /dηη 1dηη 2

0.000

0.001

0.002

-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6


Herw ig B -mesons Isajet B -mesons Pyth iaC3L B-mesons Pythia B-mesons

(1/σσ)d σσ/d ηη1d ηη2

1.8 TeV 1<|eta2|<2

1 = B -mesons 2 = Bbar-mesons

|PT1|< 10 G e V |PT2|< 10 GeV

|ph i1-ph i2|>90 deg

eta2


0) and 2 = Bbar-

mesons at 1.8 TeV with 1 < |ηη2| < 2, |φφ1-φφ2| > 90o, PT1 > 10 GeV, and PT2 > 10 GeV.

Measures PDF’s, fragmentation.


B Physics: Pseudo-Rapidity Correlations Parton & Hadron Level: Pseudo-Rapidity Correlations


0.000

0.005

0.010

0.015

0.020

-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6


Isajet b-quark Isajet b-quark Isajet B-mesons Isajet B-mesons


|eta2| < 0.5

1 < |eta2| < 2Isajet at 1.8 TeV

1 = b-quark or B-mesons2 = bbar quark or Bbar-mesons

|PT1|< 5 GeV |PT2|<5 GeV|phi1-phi2|>90 deg

Plot shows (1/σσ)dσσ/dηη1dηη2 versus ηη1, for 1 = b-quark and 2 = bbar-quark and for 1

= B-mesons (B+,B0,Bs0) and 2 = Bbar-mesons at 1.8 TeV with |ηη2| < 0.5 and with 1 <

ηη2 < 2 and |φφ1-φφ2| > 90o, PT1 > 5 GeV, and PT2 > 5 GeV.

Parton & Hadron Level: Pseudo-Rapidity Correlations


0.000

0.005

0.010

0.015

0.020

0.025

-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6

Pseudo-Rap id ity ηη11

Herwig b-quark Herwig b-quark Herwig B-mesons Herwig B-mesons

Herwig at 1.8 TeV1 = b-quark or B-mesons

2 = bbar quark or Bbar-mesons|PT1|< 5 GeV |PT2|<5 GeV

|phi1-phi2|>90 deg


|eta2| < 0.5

1 < |eta2| < 2





B Physics: Pseudo-Rapidity Correlations Parton & Hadron Level: Pseudo-Rapidity Correlations


0.000

0.005

0.010

0.015

0.020

-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6


Pythia b-quark Pythia b-quark Pythia B-mesons Pythia B-mesons

Pythia at 1.8 TeV1 = b-quark or B-mesons

2 = bbar quark or Bbar-mesons|PT1|< 5 GeV |PT2|<5 GeV

|phi1-phi2|>90 deg


|eta2| < 0.5

1 < |eta2| < 2





B Physics: Correlation Functions Hadron Level: “Normalized” Correlation Function

Pseudo-Rapidity Correlations R(ηη1)

-1.0

-0.8

-0.6

-0.4

-0.2

0.0

-4 -3 -2 -1 0 1 2 3 4



R(ηη1)

1.8 TeV |eta2| < 0.51 = B-mesons 2 =Bbar-mesons

|PT1|< 5 GeV |PT2| < 5 GeV|phi1-phi2|>90 deg

eta2

Plot shows the normalized correlation function R(ηη1) versus ηη1, for 1 = B-mesons

(B+,B0,Bs0) and 2 = Bbar-mesons at 1.8 TeV with |ηη2| < 0.5 and |φφ1-φφ2| > 90o, PT1 >

5 GeV, and PT2 > 5 GeV.

Hadron Level: “Normalized” Correlation Function

Pseudo-Rapidity Correlations R(ηη1)

-1.0

-0.8

-0.6

-0.4

-0.2

0.0

-4 -3 -2 -1 0 1 2 3 4

Pseudo-Rapidity ηη 11


1.8 TeV 1<|eta2|<21 = B-mesons 2 = Bbar-mesons

|PT1|< 5 GeV |PT2| < 5 GeV|phi1-phi2|>90 deg

R(ηη1)

eta2

Plot shows the normalized correlation function R(ηη1) versus ηη1, for 1 = B-mesons

(B+,B0,Bs0) and 2 = Bbar-mesons at 1.8 TeV with 1 < ηη2 < 2 and |φφ1-φφ2| > 90o, PT1 >

5 GeV, and PT2 > 5 GeV.

b physics: qcd monte carlo model predictionsrfield/cdf/bplots_feb25.pdf · b physics: qcd monte...

Documents