Stan Brodsky- Novel Anti-Proton QCD Physics

8/3/2019 Stan Brodsky- Novel Anti-Proton QCD Physics

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FAIRWorkshopOctober 1516, 2007

Novel AntiProton QCD Physics Stan BrodskySLAC96

5-DimensionalA nti-de Sitter

Spacet ime

4-DimensionalFlat Sp ac etime

(hologram)

Black Hole

z0 = 1/QCDz

96


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97


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98


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99


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100


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We consider both holographic models

Truncated AdS/CFT (Hard-Wall) model: cut-off at z0 = 1/QCD breaks conformal invariance and

allows the introduction of the QCD scale (Hard-Wall Model) Polchinski and Strassler (2001).

Smooth cutoff: introduction of a background dilaton field (z) usual linear Regge dependence can

be obtained (Soft-Wall Model) Karch, Katz, Son and Stephanov (2006).

101


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0 2L

4 6

2

0

4

6

8

1-20058694A7

N (939) N (1520)

N (2220)

N (1535)

N (1650)N (1675)

N (1700)

N (1680)

N (1720)

N (2190)

N (2250)

N (2600)

2

0

4

6

8

(1232)

(1620)

(1905)

(2420)

(1700)

(1910)

(1920)

(1950)

(b)

(a)

(GeV

2)

(1930)

S=3/2

S=1/2

Fig: Predictions for the light baryon orbital spectrum for QCD = 0.22 GeV

Guy de Teramond

SJB

Only oneparameter!

Phys.Rev.Lett.94:201601,2005

hep-th/0501022

Entirelight-quark

baryonspectrum

Predictionsof AdS/CFT

102


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0

2

(a) (b)

4

(GeV2)

0 2 45-2006

8694A20

(782)

(770)

a2(1320)

f2(1270)

3(1690)

3(1670)

f4(2050)

a4(2040)

L

0 2 4

n

(770)

(1450)

(1700)

M2 = 22(2n + 2L + S).

= 1

103

l k f f f d /


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-2 -1.5 -1 -0.5 00

0.2

0.4

0.6

0.8

1

-10 -8 -6 -4 -2 00

0.2

0.4

0.6

0.8

1

q2(GeV2) q2(GeV2)

Spacelike pion form factor from AdS/CFT

F(q2) F

(q2)

Truncated Space ConnementHarmonic Oscillator Connement

One parameter set by pion decay constan

Data Compilation from Baldini, Kloe and Volmer

G. de Teramond, sjb

104

l k d T l k f f f d / T


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Spacelike and Timelike Pion form factor from AdS/CFT

G. de Teramond, sjb

F(q2)

q2(GeV2)

Harmonic

OscillatorConnementscale set by piondecay constant

ln F(q2)

-10 -5 0 5 10

-3

-2

-1

0

1

2

= 0.38 GeV

105


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Q2

(GeV

2

)

1 2 3 4 5 6

0

0.2

0.4

0.6

0.8

1

Fp1 (Q

2)

F1(Q2)IF =

dzz3

F(z)J(Q, z)

I(z)

Harmonic Osciator Connemen

Truncated Space Connement = 0.2 GeV

G. de Teramond, sjb

Preliminary

Current modied

by metric

= 0.424 Ge

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Novel AntiProton QCD Physics Stan BrodskySLAC

Dirac Neutron Form Factor

(Valence Approximation)

Q4Fn1 (Q2) [GeV4]

1 2 3 4 5 6

-0.35

-0.3

-0.25

-0.2

-0.15

-0.1

-0.05

0

Q2 [GeV2]

Prediction for Q4Fn1 (Q2) for QCD = 0.21 GeV in the hard wall approximation. Data analysis from

Diehl (2005).

107

Truncated Space Connement

107

Sp lik P li F F t


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0 1 2 3 4 5 6

0

0.5

1

1.5

2

Spacelike Pauli Form Factor

Q2(GeV2)

Harmonic OscillatorConnement

Normalized to anomalousmoment

Fp2 (Q2)

= 0.49 eV

G. de Teramond, sjb

PreliminaryFrom overlap of L = 1 and L = 0 LFWFs

108

N t C t ib ti t M F F t t L Q i AdS/QCD


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Note: Contributions to Mesons Form Factors at Large Q in AdS/QCD

Write form factor in terms of an effective partonic transverse density in impact space b

F(q2) = 1

0

dx db2 (x,b,Q),with

(x,b,Q) = J0 [b Q(1 x)] |

(x, b)|2 and b = |b|.

Contribution from (x,b,Q) is shifted towards small |b| and large x 1 as Q increases.

0

0.2

0.4

0

0.5

1.0

0

0.5

1.0

0102001020

0

0.2

0.4

QC


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Stan BrodskySLAC


Novel AntiProton QCD Physics110

AdS/CFT: Duality between string theory in AntideSitter Space and Conformal Field Theory

New Way to Implement Conformal Symmetry

Holographic Model: Conformal Symmetry at Short

Distances, Connement at large distances

Remarkable predictions for hadronic spectra,wavefunctions, interactions

AdS/CFT provides novel insights into the quarkstructure of hadrons

New Perspectives on QCDPhenomena from AdS/CFT

110


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Holography:


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V() = 1 4L2

42.Eective conformal

potential:

Holography:Map AdS/CFT to 3+1 LF Theory

2 = x(1 x)b2.

Relativistic radial equation:

G. de Teramond, sjb

d

2

d2+ V()

() = M2()

x

(1 x)

b

Frame Independent

112112

x


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(x,b)00.20.40.60.81

1

2

3

4

0

0.25

0.5

0.75

1

b[GeV1]

Two-parton ground state LFWF in impact space (x, b) for a for n = 2, = 0, k = 1.

AdS/CFT

prediction formeson LFWF

Guy de TeramondSJB

= bx(1 x)

Holographic Model

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String Theory

AdS/CFT

Semi-Classical QCD / Wave EquationsSemi-Classical QC Wave Equations

Mapping of Poincare andConformal SO(4,2) symmetries of 3

+1 spaceto AdS5 space

Integrable!Boost Invariant 3+1 Light-Front Wave EquationsBoost Invariant 3+1 Li t-Front Wave Equations

Hadron Spectra, Wavefunctions, Dynamics

AdS/QCDConformal behavior at short

distances+ Confinement at large

distance

Counting rules for HardExclusive ScatteringRegge Trajectories

Holography

J =0,1,1/2,3/2 plus L

Goal: First Approximant to QCD

QCD at the Amplitude Level

114114

N l D i l T f QCD FAIR


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Stan BrodskySLAC


Novel AntiProton QCD Physics

Novel Dynamical Tests of QCD at FAIR

115

Characteristic momentum scale of QCD: 300 MeV

Many Tests of AdS/CFT predictions possible

Exclusive channels: Conformal scaling laws, quarkinterchange

pp scattering: fundamental aspects of nuclear force

Color transparency: Coherent color eects

Nuclear Eects, Hidden Color, AntiShadowing

Anomalous heavy quark phenomena

S in Eects: AN, ANN

115

Nucleon Form Factors


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Nucleon Form Factors

N

N

(q)

(q)

e

eNucleon current operator (Dirac & Pauli)

(q) =

F1(q2

) +

i

2MN

qF2(q2

)

Electric and Magnetic Form Factors

GE(q2) = F1(q

2) + F2(q2)

GM(q2) = F1(q2) + F2(q2)

=q2

4M2N

e pe

p

Elastic scattering

d

d =2E

e

cos2

24E3e sin

4 2

G2E + 1 + 2(1 + ) tan2 2G2M 11 +

e e+

p

p

Annihilation

d

d=

21 1/4q2

(1 + cos2 )|GM|

2 +1

sin2 |GE|

2

Simone Pacetti Ratio |GpE

(q2)/GpM

(q2)| and dispersion relations

e+e pp

ep ep

116

l


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u

P

P

u

u

u

d

d

e+

e

*

Exclusive Processes

e

+

e

ppProbability decreases with number of constituents!

R(e+e HH) |F(s)|2

s = (Ee+ + Ee)2

|F(s)| [1s ]nq1

117

1


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Phenomenological success of dimensional scaling laws for exclusive processes

d/dt 1/sn2, n = nA + nB + nC + nD,

implies QCD is a strongly coupled conformal theory at moderate but not asymptotic energies

Farrar and sjb (1973); Matveev et al. (1973).

Derivation of counting rules for gauge theories with mass gap dual to string theories in warped space

(hard behavior instead of soft behavior characteristic of strings) Polchinski and Strassler (2001).

5 10 15 20 25 30 35

0.2

0.4

0.6

0.8

Q2 [GeV2]

Q4Fp1

(Q2) [GeV4]

F1(Q2) 1/Q

2

n1

, n = 3

From: M. Diehl et al. Eur. Phys. J. C 39, 1 (2005).

measured inelectron-proton

elastic scattering

118

Brodsky and Farrar, Phys. Rev. Lett. 31 (1973) 115Matveev et al., Lett. Nuovo Cimento, 7 (1973) 719


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Stan BrodskySLAC



Quark Counting Rules for

Exclusive Processes Powerlaw fallo of the scattering rate reects

degree of compositeness

The more composite the faster the fallo

Powerlaw counts the number of quarks and gluonconstituents

Form factors: probability amplitude to stay intact

FH(Q) 1(Q2)n1 n = # elementary constituents

, , ( )

119

PQCD and Exclusive Processes Lepage; SJBEf R d ki


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Stan BrodskySLAC



PQCD and Exclusive Processes

Iterate kernel of LFWFs when at high virtuality; distributionamplitude contains all physics below factorization scale

Rigorous Factorization Formulae: Leading twist

Underly Exclusive Bdecay analyses

Distribution amplitude: gauge invariant, OPE, evolutionequations, conformal expansions

BLM scale setting: sum nonconformal contributions in scaleof running coupling

Derive Dimensional Counting Rules/ Conformal Scaling

M = dxidyiF(x, Q)TH(xi, yi, Q)I(yi, Q)Efremov, Radyuskin

120

Ti lik t f f t i PQCD


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u

P

P

u

u

u

d

d

e+

e

*

Timelike proton form factor in PQCD

GM(Q2)

2s(Q

2

)Q4

n,m

bnm

logQ2

2Bn +Bn

1 + Os(Q

2

),m2

Q2

.

Lepage and Sjb

121

Timelike Proton Form Factor


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Nicolas Berger 122icolas Berger 1

Define Effective form factor by

Peak at threshold, sharp dips at 2.25 GeV,3.0 GeV.

Good fit to pQCD prediction for high mpp.

N. Berger

F(s) log

2 s

2

s2

122

Time-like Form Factors


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Time-like Form Factors

All data measure absolute crosssection GE = GM

PANDA will provide independentmeasurement of GE and GM

widest kinematic range in a singleexperiment

Time-like form factors are complex

precision experiments will revealthese structures

PANDA rangeB. Seitz

123

More to ex lore


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More to ex lore

Time-like form factors are analytically connected to space-like form factors

Time-like form factors are complex, get phase in addition

expect a rich structure in time-like region from dispersion relation model

even more to learn from single spin asymmetries

Hep:-ph/0507085

R. Baldini et al. EPJ C 46(2006) 412

B. Seitz

124

K QCD E i t t FAIR


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Key QCD Experiment at FAIR



Measurement of hadron time-like form factorsangular distributions

Test QCD Counting RulesConformal Symmetry: AdS/CFTHadron Helicity Conservation

FH(s) [1s ]

nH1

Leading power inQCD

e+

ep

p Separate F1, F2

125

3.03850605-007 4.0

3 5

3850605-006


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2.5

2.0

1.5

1.0

0.5

0 2 4 6 8 10 12 14

Q2 (GeV2)

[Q4

GM

(Q2)]/

p

(GeV2)

PreliminaryCLEO

3.5

3.0

2.5

2.0

1.5

1.0

0.5

0 2 4 6 8 10 12 14

Q2 (GeV2)

Q2

FK(Q2)(GeV2)

Preliminary

CLEO

Proton timelike form factor. Kaon timelike form factor.

Q2|FK(13.48 GeV2)| = 0.85 0.05(stat) 0.02(syst) GeV2

Q4|GpM(13.48 GeV2)| = 2.54 0.36(stat) 0.16(syst) GeV4

The proton magnetic form factor result agrees with that measured in the reverse

reaction pp e+e at Fermilab. The kaon form factor measurement is the first

ever direct measurement at |Q2| > 4 GeV2.

orthwestern University 16 K. K. Seth

New results from CLEO

126

T h h l d


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H+

H

e+

e

One-photon/two-photoninterference gives electron-

positron asymmetry

Small Eect from Z0

Twophoton exchange correction, elastic andinelastic nucleon channels, give signicant;

interference with onephoton exchange, destroysRosenbluth method

Blunden, Melnitchouk; Afanasev, Chen,Carlson, Vanderhaegen, sjb

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Py

sin 2 Im GE*GM

D 1 sin 2 ImF2*F1

D

e+

ep

p

polarized

129

Single-spin polarization effects and the determination of timelike proton form factors


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Carlson, Hiller,Hwang, sjb

DGM21cos2

1

GE

2sin2;

PzPe2 cos GM

2

D

Requires beam andlepton polarization

130

Single-spin polarization effects and the determination of timelike proton form factors


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Carlson, Hiller,Hwang, sjb

PxPe2 sin ReGE*GM

D

DGM21cos2

1

GE

2sin2;

Requires beam and leptonpolarization

131

Quark-Counting: ddt (pp pp) =

F(CM)s10

n = 4 3 2 = 10


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Q gdt (pp pp) s10

n = 9.7 0.5

Best Fit

cm2

GeV2

Reects

underlyingconformalscalefree

interactions

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ddt (pp pp) at large pT

Test PQCD AdS/CFT conformal scaling:twist = dimension - spin = 12

M(s, t) F(t/s)

s4ddt (pp pp)

|F(t/s)|2

s10

Test color transparency

Test Quark Interchange Mechanism

Single-spin asymmetry AN

Exclusive Transversity ANN

p

p

p

p

ddt )

| (t/s)|2

s10

Study Fundamental Aspects ofNuclear Force

M 1s2u2

133


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21010 2

Compton-Scattering Cross Section on the Proton at High Momentum Transfer


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)2

-t (GeV

0 2 4 6 8

)2

/dt(nb/GeV

d

-410

-210

1

101

10

2

s = 11. GeV

2s = 8.9 GeV

2s = 6.8 GeV

(deg)cm60 80 100 120

)cm

n(

4

5

6

7

8

9

Jeerson LabHall A

Collaboration

5Open points: Cornell measurementM. A. Shupe et al., Phys. Rev. D 19, 1921 1979.

pQCDn=6

Compton at fixed angles fallsfaster than photoproduction!

Alan Nathan, et al

135

Ratio of Real Compton-Scattering Cross Sectionto Electron -Proton Scattering at Fixed CM Angle


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A. Nathan

Ratiobecomes

energy-independentat large s ?

136

" " f t f t


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1.0

1.5

2.0

2.5

3.0

3.5

2 3 4 5 6 7-t (GeV

2)

RV/dipole

s=7 s=9 s=11

F1/dipole

" "

V A f t f t t t

Agrees with PQCD

137


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Cross section comparisonCross section comparison ppBelle


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#*"!'%#! "($$%!'#&"$$%#+!',

"!'&&" $

#%)!#"'

!-&

0.2 pb

ppFermilab

PANDA pp

139


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Processes of interest:Processes of interest:--process is not only background but also signal!process is not only background but also signal!



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43

p y g g

$"#

"!

"

&"!!!!& !!

"! "#%2

142

142



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p

p

ddt (pp ) at fixed angle, large pT

ddt (pp ) =

F(t/s)s6

Tests PQCD and AdS/CFT Conformal Scaling

AngleIndependent J=0 Fixed Pole Contribution:

M(pp ) = F(s) 1

s2

Local TwoPhotonSeagull Interaction

d

dt(pp )

1

s6

Close, Gunion, sjb

143

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Stan Brodsky- Novel Anti-Proton QCD Physics

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