[PPT] - A pivotal year for Generalized Parton Distributions Pivotal year PowerPoint Presentation

SLIDE 1

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

A pivotal year for Generalized Parton Distributions

J. Ball, G. Charles, B. Moreno, H. Moutarde, F. Sabati´

e,

S. Procureur

Irfu/SPhN, CEA-Saclay

Hadron 2011 - 14 / 06 / 2011

1

2011 situation

2

Status of GPD analysis of data

3

Future orientations

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 1 / 16

SLIDE 2

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

Generalized Parton Distributions.

Viewing nucleon structure in 3d.

e− DIS e− γ Q2 p X γ, Q2 nucleon Parton Distributions

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 2 / 16

SLIDE 3

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

Generalized Parton Distributions.

Viewing nucleon structure in 3d.

e− DVCS e− γ Q2 p γ p t γ, Q2 nucleon Parton Distributions Generalized γ, Q2 by bx Correlation of the longitudinal momentum and the transverse position of the struck quark.

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 2 / 16

SLIDE 4

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

Generalized Parton Distributions.

Viewing nucleon structure in 3d.

e− DVCS e− γ Q2 p γ p t e− DVMP e− γ Q2 p π, ρ, . . . p t Correlation of the longitudinal momentum and the transverse position of the struck quark. 3-dimensional description of the nucleon. Insights on :

spin structure, energy-momentum structure.

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 2 / 16

SLIDE 5

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

Generalized Parton Distributions.

Viewing nucleon structure in 3d.

e− DVCS e− γ, Q2 p p t γ x + ξ x − ξ

factorization

e− DVMP e− γ, Q2 p p t x + ξ x − ξ π, ρ, . . .

factorization

Correlation of the longitudinal momentum and the transverse position of the struck quark. 3-dimensional description of the nucleon. Insights on :

spin structure, energy-momentum structure.

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 2 / 16

SLIDE 6

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

Generalized Parton Distributions.

Viewing nucleon structure in 3d.

e− DVCS e− γ, Q2 p p t γ x + ξ x − ξ

factorization

γ, Q2 nucleon Parton Distributions Generalized H(x, ξ, t) E(x, ξ, t) ˜ H(x, ξ, t) ˜ E(x, ξ, t) γ, Q2 by bx Obtain this 3d picture from DVCS / DVMP measurements ?

x ~ 0.3 x x < 0.01 ~ 0.1

spin transverse (c)

b xP

longitud. (a) t r a n s v e r s e pion cloud quarks valence (b) quarks, gluons singlet quarks move faster slower

C. Weiss,

AIP Conf.

Proc. 1149,

150 (2009)

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 2 / 16

SLIDE 7

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

DVCS described by 4 Compton Form Factors.

Approximations : quark sector, leading twist and leading order.

Example : GPD F = H, E (−) or ˜ H, ˜ E (+). F = +1

−1

dx F(x, ξ, t)

1

ξ − x − iǫ ∓ 1 ξ + x − iǫ

Integration yields real and imaginary parts to F :

Compton Form Factor at Leading Order ReF = P +1

−1

dx F(x, ξ, t)

1

ξ − x ∓ 1 ξ + x

ImF

= π

F(ξ, ξ, t) ∓ F(−ξ, ξ, t)
Existence of dispersion relations at fixed t.
H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 3 / 16

SLIDE 8

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

(Part of) Selected DVCS measurements.

Fine kinematic binning, large kinematic coverage, several observables.

JLab Hall A : helicity-dependent and independent cross sections

C. Mu˜

noz Camacho et al., Phys. Rev. Lett. 97, 262002 (2006) Restricted kinematic range, highly-precise helicity-dependent cross sections. JLab Hall B : Beam Spin Asymmetries F.-X. Girod et al., Phys. Rev. Lett. 100, 162002 (2008) Wide kinematic range, precise BSAs. Hermes : BSAs, BCAs, TSAs

A. Airapetian et al., JHEP 0806, 017 (2008)
D. Zeiler et al., arXiv:0810.5007 [hep-ex]

Restricted kinematic range, several different observables.

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 4 / 16

SLIDE 9

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

(Part of) Selected DVCS measurements.

Fine kinematic binning, large kinematic coverage, several observables.

JLab Hall A : helicity-dependent and independent cross sections

C. Mu˜

noz Camacho et al., Phys. Rev. Lett. 97, 262002 (2006) Restricted kinematic range, highly-precise helicity-dependent cross sections. JLab Hall B : Beam Spin Asymmetries F.-X. Girod et al., Phys. Rev. Lett. 100, 162002 (2008) Wide kinematic range, precise BSAs. Hermes : BSAs, BCAs, TSAs (Update in progress)

A. Airapetian et al., JHEP 0806, 017 (2008)
D. Zeiler et al., arXiv:0810.5007 [hep-ex]

Restricted kinematic range, several different observables.

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 4 / 16

SLIDE 10

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

Overview of current extraction methods.

Problems : Model dependence ? Degrees of freedom ? Extrapolations ?

Local fits Take each kinematic bin independantly of the others. Extraction of ReH, ImH, . . . as independent parameters. Global fit Take all kinematic bins at the same time. Use a parametrization of GPDs or CFFs. Hybrid : Local / global fit Combine two previous methods to estimate model dependence. Neural networks Already used ofr PDF fits. In progress for GPDs.

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 5 / 16

SLIDE 11

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

Overview of current extraction methods.

Problems : Model dependence ? Degrees of freedom ? Extrapolations ?

Local fits Take each kinematic bin independantly of the others. Extraction of ReH, ImH, . . . as independent parameters.

HIm(xB=.25,t) H

~ Im(xB=.25,t)

r ◦ :

”7-CFF” fit results. ♦ : ”H − ˜ H” fit results. + : VGG.

M. Guidal, Phys. Lett. B689 (2010) 156
H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 5 / 16

SLIDE 12

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

Overview of current extraction methods.

Problems : Model dependence ? Degrees of freedom ? Extrapolations ?

Global fit Take all kinematic bins at the same time. Use a parametrization of GPDs or CFFs.

t 0.28 GeV2

Q2 2 GeV2

HALL A CLAS CLAS CLAS HERMES

0.10 0.15 0.20 0.25 0.30 0.35 1 2 3 4

xB

Im xB,t,Q2Π

Without Hall A data. With Hall A data. △ : neural network. : ”7-CFF” fit results. ⋄ : ”H − ˜ H”.

: hybrid fits.
K. Kumericki and D. M¨

uller, Exclusive 2010

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 5 / 16

SLIDE 13

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

Overview of current extraction methods.

Problems : Model dependence ? Degrees of freedom ? Extrapolations ?

Global fit Take all kinematic bins at the same time. Use a parametrization of GPDs or CFFs. BSA at 90◦. Test of ˜ H contribution. Negligible E contribution.

G. Goldstein et al, arXiv:1012.3776
H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 5 / 16

SLIDE 14

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

Overview of current extraction methods.

Problems : Model dependence ? Degrees of freedom ? Extrapolations ?

Hybrid : Local / global fit Combine two previous methods to estimate model dependence.

0.1 0.2 0.3 0.1 0.2 0.3 0.1 0.2 0.3 0.1 0.2 0.3 0.4

B

x

B

x

B

x

B

x

10
5

5 5 10 15 ReH ImH

2

t = -0.15 GeV

2

t = -0.30 GeV

2

t = -0.50 GeV

2

t = -0.80 GeV

2.5 5 7.5 10 12.5 15

10
7.5
5
2.5

2.5 5 7.5

VGG arXiv:1003.0307

2.5 5 7.5 10 12.5 15

10
7.5
5
2.5

2.5 5 7.5 2.5 5 7.5 10 12.5 15

10
7.5
5
2.5

2.5 5 7.5 2.5 5 7.5 10 12.5 15

10
7.5
5
2.5

2.5 5 7.5

Comparison to VGG model on JLab Hall B kinematics. Loss of information during the extraction.

H. Moutarde, Phys. Rev. D79 (2009) 094021
H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 5 / 16

SLIDE 15

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

Overview of current extraction methods.

Problems : Model dependence ? Degrees of freedom ? Extrapolations ?

Neural networks Already used ofr PDF fits. In progress for GPDs. HERMES BCAs and CLAS BSAs. Extrapolation t → 0.

K. Kumericki and D. M¨

uller, Exclusive 2010

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 5 / 16

SLIDE 16

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

Universality.

Same GPDs extracted in DVCS and DVMP ?

DVCS and DVMP measurements since the early 2000’s. Extractions of GPDs from DVCS and DVMP since ≃ 2008. Current DVCS kinematics suitable for GPD analysis. Situation less clear for DVMP. First step : Compare GPDs extracted from DVCS and DVMP measurements. Input : S. Goloskokov and P. Kroll (GK) GPD model.

S. Goloskokov and P. Kroll, Eur. Phys. J. C42 (2005) 281
S. Goloskokov and P. Kroll, Eur. Phys. J. C53 (2008) 367

Designed for DVMP analysis. Double Distribution model.

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 6 / 16

SLIDE 17

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

Universality.

Same GPDs extracted in DVCS and DVMP ?

JLab Hall B. Data with

|t| Q2 < 1 2.

Data with

|t| Q2 ≥ 1 2.

0.090000<|t|<0.200000 GeV^2 =5.25

2

χ

)

2

(GeV

2

Q 1 2 3 4

B

x 0.1 0.2 0.3 0.4 0.5

90 180 270 360

0.35
0.175

0.175 0.35 ReH=-0.81 ImH=16.74 90 180 270 360 0.175 ReH=-0.39 ImH=12.40 90 180 270 360 0.175 ReH=-0.45 ImH=11.98 90 180 270 360

0.35
0.175

0.175 0.35

ReH=0.23 ImH=8.90

90 180 270 360

0.35
0.175

0.175 0.35

ReH=0.30 ImH=8.69

90 180 270 360

0.35
0.175

0.175 0.35

ReH=0.39 ImH=8.30

90 180 270 360

0.35
0.175

0.175 0.35

ReH=0.64 ImH=6.04

90 180 270 360

0.35
0.175

0.175 0.35

ReH=0.65 ImH=5.93

90 180 270 360

0.35
0.175

0.175 0.35

ReH=0.65 ImH=5.84

90 180 270 360

0.35
0.175

0.175 0.35

ReH=0.66 ImH=5.79

) ° ( φ 90 180 270 360

LU

A

0.35
0.175

0.175 0.35

ReH=-0.81 ImH=16.74

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 6 / 16

SLIDE 18

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

Universality.

Same GPDs extracted in DVCS and DVMP ?

JLab Hall B. Data with

|t| Q2 < 1 2.

Data with

|t| Q2 ≥ 1 2.

0.200000<|t|<0.400000 GeV^2 =5.25

2

χ

)

2

(GeV

2

Q 1 2 3 4

B

x 0.1 0.2 0.3 0.4 0.5

90 180 270 360

0.35
0.175

0.175 0.35 ReH=-1.67 ImH=11.11 90 180 270 360 0.175 ReH=-1.15 ImH=8.58 90 180 270 360 0.175 ReH=-1.16 ImH=8.30 90 180 270 360

0.35
0.175

0.175 0.35

ReH=-0.36 ImH=6.21

90 180 270 360

0.35
0.175

0.175 0.35

ReH=-0.32 ImH=6.12

90 180 270 360

0.35
0.175

0.175 0.35

ReH=-0.28 ImH=5.97

90 180 270 360

0.35
0.175

0.175 0.35

ReH=0.19 ImH=4.35

90 180 270 360

0.35
0.175

0.175 0.35

ReH=0.25 ImH=4.29

90 180 270 360

0.35
0.175

0.175 0.35

ReH=0.30 ImH=4.26

90 180 270 360

0.35
0.175

0.175 0.35

ReH=0.35 ImH=4.20

90 180 270 360

0.35
0.175

0.175 0.35 ReH=0.53 ImH=2.99 90 180 270 360

0.35
0.175

0.175 0.35

ReH=0.56 ImH=2.90

90 180 270 360

0.35
0.175

0.175 0.35

ReH=0.55 ImH=2.86

) ° ( φ 90 180 270 360

LU

A

0.35
0.175

0.175 0.35

ReH=-1.67 ImH=11.11

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 6 / 16

SLIDE 19

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

Universality.

Same GPDs extracted in DVCS and DVMP ?

JLab Hall B. Data with

|t| Q2 < 1 2.

Data with

|t| Q2 ≥ 1 2.

0.400000<|t|<0.600000 GeV^2 =5.25

2

χ

)

2

(GeV

2

Q 1 2 3 4

B

x 0.1 0.2 0.3 0.4 0.5

90 180 270 360

0.35
0.175

0.175 0.35 ReH=-1.96 ImH=6.37 90 180 270 360 0.175 ReH=-1.52 ImH=5.10 90 180 270 360 0.175 ReH=-1.50 ImH=4.97 90 180 270 360

0.35
0.175

0.175 0.35

ReH=-0.80 ImH=3.91

90 180 270 360

0.35
0.175

0.175 0.35

ReH=-0.81 ImH=3.91

90 180 270 360

0.35
0.175

0.175 0.35

ReH=-0.78 ImH=3.85

90 180 270 360

0.35
0.175

0.175 0.35

ReH=-0.23 ImH=3.02

90 180 270 360

0.35
0.175

0.175 0.35

ReH=-0.17 ImH=2.95

90 180 270 360

0.35
0.175

0.175 0.35

ReH=-0.12 ImH=2.91

90 180 270 360

0.35
0.175

0.175 0.35

ReH=-0.08 ImH=2.87 90 180 270 360

0.35
0.175

0.175 0.35 ReH=0.23 ImH=2.28 90 180 270 360

0.35
0.175

0.175 0.35

ReH=0.29 ImH=2.16

90 180 270 360

0.35
0.175

0.175 0.35

ReH=0.30 ImH=2.13

) ° ( φ 90 180 270 360

LU

A

0.35
0.175

0.175 0.35

ReH=-1.96 ImH=6.37

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 6 / 16

SLIDE 20

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

Universality.

Same GPDs extracted in DVCS and DVMP ?

JLab Hall B. Data with

|t| Q2 < 1 2.

Data with

|t| Q2 ≥ 1 2.

0.600000<|t|<1.000000 GeV^2 =5.25

2

χ

)

2

(GeV

2

Q 1 2 3 4

B

x 0.1 0.2 0.3 0.4 0.5

90 180 270 360

0.35
0.175

0.175 0.35 ReH=-1.70 ImH=2.98 90 180 270 360 0.175 ReH=-1.40 ImH=2.46 90 180 270 360 0.175 ReH=-1.40 ImH=2.51 90 180 270 360

0.35
0.175

0.175 0.35

ReH=-0.95 ImH=2.17

90 180 270 360

0.35
0.175

0.175 0.35

ReH=-0.94 ImH=2.17

90 180 270 360

0.35
0.175

0.175 0.35

ReH=-0.91 ImH=2.15

90 180 270 360

0.35
0.175

0.175 0.35

ReH=-0.45 ImH=1.82

90 180 270 360

0.35
0.175

0.175 0.35

ReH=-0.40 ImH=1.80

90 180 270 360

0.35
0.175

0.175 0.35

ReH=-0.38 ImH=1.80

90 180 270 360

0.35
0.175

0.175 0.35

ReH=-0.37 ImH=1.81 90 180 270 360

0.35
0.175

0.175 0.35 ReH=-0.10 ImH=1.47 90 180 270 360

0.35
0.175

0.175 0.35

ReH=-0.01 ImH=1.41 90 180 270 360

0.35
0.175

0.175 0.35

ReH=0.05 ImH=1.38

) ° ( φ 90 180 270 360

LU

A

0.35
0.175

0.175 0.35

ReH=-1.70 ImH=2.98

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 6 / 16

SLIDE 21

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

Universality.

Same GPDs extracted in DVCS and DVMP ?

JLab Hall B. Data with

|t| Q2 < 1 2.

Data with

|t| Q2 ≥ 1 2.

1.000000<|t|<1.800000 GeV^2 =5.25

2

χ

)

2

(GeV

2

Q 1 2 3 4

B

x 0.1 0.2 0.3 0.4 0.5

90 180 270 360

0.35
0.175

0.175 0.35 ReH=-1.00 ImH=0.82 90 180 270 360 0.175 ReH=-0.90 ImH=0.78 90 180 270 360 0.175 ReH=-0.90 ImH=0.79 90 180 270 360

0.35
0.175

0.175 0.35

ReH=-0.69 ImH=0.72

90 180 270 360

0.35
0.175

0.175 0.35

ReH=-0.69 ImH=0.73

90 180 270 360

0.35
0.175

0.175 0.35

ReH=-0.68 ImH=0.76

90 180 270 360

0.35
0.175

0.175 0.35

ReH=-0.45 ImH=0.69

90 180 270 360

0.35
0.175

0.175 0.35

ReH=-0.43 ImH=0.71

90 180 270 360

0.35
0.175

0.175 0.35

ReH=-0.42 ImH=0.71

90 180 270 360

0.35
0.175

0.175 0.35

ReH=-0.42 ImH=0.71 90 180 270 360

0.35
0.175

0.175 0.35 ReH=-0.24 ImH=0.71 90 180 270 360

0.35
0.175

0.175 0.35

ReH=-0.18 ImH=0.69 90 180 270 360

0.35
0.175

0.175 0.35

ReH=-0.13 ImH=0.68

) ° ( φ 90 180 270 360

LU

A

0.35
0.175

0.175 0.35

ReH=-1.00 ImH=0.82

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 6 / 16

SLIDE 22

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

Universality.

Same GPDs extracted in DVCS and DVMP ?

JLab Hall A. Data with

|t| Q2 < 1 2.

Data with

|t| Q2 ≥ 1 2.

) ° ( φ 60 120 180 240 300 360 0.0449 0.055 0.0652 0.0753 0.0855 0.0956

ReH=0.89 ImH=5.22

) ° ( φ 60 120 180 240 300 360

0.0129
0.0074
0.0019

0.0036 0.009 0.0145 ) ° ( φ 60 120 180 240 300 360 0.0312 0.0453 0.0593 0.0734 0.0874 0.1014

ReH=0.60 ImH=4.66

) ° ( φ 60 120 180 240 300 360

0.0225
0.0142
0.0059

0.0024 0.0107 0.0191 ) ° ( φ 60 120 180 240 300 360 0.024 0.0392 0.0545 0.0697 0.0849 0.1002

ReH=0.41 ImH=4.25

) ° ( φ 60 120 180 240 300 360

0.0206
0.0117
0.0028

0.0062 0.0151 0.024 ) ° ( φ 60 120 180 240 300 360 0.0238 0.0397 0.0556 0.0716 0.0875 0.1035

ReH=0.24 ImH=3.88

) ° ( φ 60 120 180 240 300 360

0.0201
0.0133
0.0065

0.0003 0.0071 0.0139

)

4

=-1)) (nb/GeV

e

(h σ =+1)-

e

(h σ ( 2 1 )

4

=-1)) (nb/GeV

e

(h σ =+1)+

e

(h σ ( 2 1

t=-0.33 GeV^2 t=-0.28 GeV^2 t=-0.23 GeV^2 t=-0.17 GeV^2

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 6 / 16

SLIDE 23

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

Universality.

Same GPDs extracted in DVCS and DVMP ?

JLab Hall A. Data with

|t| Q2 < 1 2.

Data with

|t| Q2 ≥ 1 2.

) ° ( φ 60 120 180 240 300 360

0.0222
0.0136
0.005

0.0035 0.0121 0.0207

ImH=5.48 ) ° ( φ 60 120 180 240 300 360

0.024
0.0146
0.0053

0.0041 0.0134 0.0228

ImH=4.89 ) ° ( φ 60 120 180 240 300 360

0.0336
0.0216
0.0096

0.0024 0.0144 0.0264

ImH=4.45 ) ° ( φ 60 120 180 240 300 360

0.0303
0.0182
0.0061

0.006 0.0181 0.0302

ImH=4.05 ) ° ( φ 60 120 180 240 300 360

0.0152
0.0086
0.0019

0.0047 0.0114 0.018

ImH=5.32 ) ° ( φ 60 120 180 240 300 360

0.0237
0.0142
0.0047

0.0047 0.0142 0.0237

ImH=4.75 ) ° ( φ 60 120 180 240 300 360

0.0196
0.0122
0.0048

0.0027 0.0101 0.0176

ImH=4.32 ) ° ( φ 60 120 180 240 300 360

0.0249
0.0155
0.0062

0.0031 0.0125 0.0218

ImH=3.94 ) ° ( φ 60 120 180 240 300 360

0.0129
0.0074
0.0019

0.0036 0.009 0.0145

ImH=5.22 ) ° ( φ 60 120 180 240 300 360

0.0225
0.0142
0.0059

0.0024 0.0107 0.0191

ImH=4.66 ) ° ( φ 60 120 180 240 300 360

0.0206
0.0117
0.0028

0.0062 0.0151 0.024

ImH=4.25 ) ° ( φ 60 120 180 240 300 360

0.0201
0.0133
0.0065

0.0003 0.0071 0.0139

ImH=3.88

)

4

=-1)) (nb/GeV

e

(h σ =+1)-

e

(h σ ( 2 1

t=-0.17 GeV^2 t=-0.23 GeV^2 t=-0.28 GeV^2 t=-0.33 GeV^2 Q^2=2.30 GeV^2 Q^2=1.90 GeV^2 Q^2=1.50 GeV^2

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 6 / 16

SLIDE 24

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

Universality.

Same GPDs extracted in DVCS and DVMP ?

Similar VGG results (χ2/dof ≃ 5.86).

M. Vanderhaeghen, P. Guichon and M. Guidal
Phys. Rev. D60 (1999) 094017 K. Goeke, M.V. Polyakov

and M. Vanderhaeghen

Prog. Part. Nucl. Phys. 47 (2001) 401

Fair agreement between GK model and extractions for H. Further studies needed to clarify the situation (and

ptimize GPD extractions !).

Work in progress.

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 6 / 16

SLIDE 25

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

Key results.

Common features of different extractions.

Dominance of twist 2 and validity of a GPD analysis of DVCS data. ImH best determined. Large uncertainties on ReH. However sizeable higher twist contamination for DVCS measurements. Already some indications about the (in)validity of the H-dominance hypothesis. Today cross-sections seem a bigger constraint to phenomenology than BSAs. Question : What observable should be measured ? Accuracy ?

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 7 / 16

SLIDE 26

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

COMPASS-II.

Kinematic domain in between collider and fixed-target experiments.

Access to several

bservables with beam

spin and charge differences. Proposal COMPASS-II (2010)

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 8 / 16

SLIDE 27

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

JLab’s 12 GeV upgrade.

Dealing with 1 % statistical accuracy.

Projection : CLAS12 data. Tentative fit. Preliminary !

0.25 GeV^2 < t < -0.15 GeV^2

= 7.63

2

χ

Chi2/Bin[ 32 ] = 50.63 ReH=-1.24 (0.03) ImH=7.39 (0.10)

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 9 / 16

SLIDE 28

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

JLab’s 12 GeV upgrade.

Dealing with 1 % statistical accuracy.

Projection : CLAS12 data. Tentative fit. Preliminary !

0.35 GeV^2 < t < -0.25 GeV^2

= 7.63

2

χ

0.35 0.7

Chi2/Bin[ 45 ] = 20.45 ReH=-2.08 (0.06) ImH=3.74 (0.20)

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 9 / 16

SLIDE 29

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

JLab’s 12 GeV upgrade.

Dealing with 1 % statistical accuracy.

Projection : CLAS12 data. Tentative fit. Preliminary !

0.55 GeV^2 < t < -0.35 GeV^2

= 7.63

2

χ

0.35 0.7

Chi2/Bin[ 46 ] = 47.01 ReH=-2.06 (0.06) ImH=4.10 (0.22)

)

2

(GeV

2

Q 2 4 6 8

B

x 0.2 0.3 0.4 0.5 0.6

1.5708 3.1416 4.7124 6.2832

0.7
0.35

0.35 0.7

1.5708 3.1416 4.7124 6.2832

0.7
0.35

0.35 0.7 Chi2/Bin[ 52 ] = 31.19 ReH=0.46 (0.40) ImH=7.60 (0.32)

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 9 / 16

SLIDE 30

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

JLab’s 12 GeV upgrade.

Dealing with 1 % statistical accuracy.

Projection : CLAS12 data. Tentative fit. Preliminary !

1.00 GeV^2 < t < -0.55 GeV^2

= 7.63

2

χ

0.35 0.7

Chi2/Bin[ 47 ] = 40.79 ReH=-2.28 (0.07) ImH=3.30 (0.24)

)

2

(GeV

2

Q 2 4 6 8

B

x 0.2 0.3 0.4 0.5 0.6

1.5708 3.1416 4.7124 6.2832

0.7
0.35

0.35 0.7

0.35 0.7

Chi2/Bin[ 54 ] = 33.18 ReH=-1.25 (0.52) ImH=2.87 (0.42)

)

2

(GeV

2

Q 2 4 6 8

B

x 0.2 0.3 0.4 0.5 0.6

1.5708 3.1416 4.7124 6.2832

0.7
0.35

0.35 0.7

Chi2/Bin[ 55 ] = 24.15 ReH=-1.60 (0.55) ImH=2.85 (0.44)

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 9 / 16

SLIDE 31

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

JLab’s 12 GeV upgrade.

Dealing with 1 % statistical accuracy.

χ2/dof ≃ 7.63 goes to 6.91 assuming more realistic 5 % uncertainty (statistical + systematic). Despite high χ2, fair agreement with previous extractions

f H at 6 GeV.

Need careful analysis to see the (low) quality of the fit ! Current hypothesis (H-dominance, . . . ) no longer useable. What observable should be measured ? High precision asymmetries seem a big constraint !

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 9 / 16

SLIDE 32

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

Local fits.

Is the accuracy sufficient for model-independent fitting ?

Structure of BSA at twist 2 (Guichon-Vanderhaeghen formalism) : BSA = a sin φ + b sin 2φ 1 + c cos φ + d cos 2φ + e cos 3φ where a = O(Q−1) d = O(Q−2) b = O(Q−4) e = O(Q−5) c = O(Q−1) Underconstrained problem (8 fit parameters : real and imaginary parts of 4 CFFs H, E, ˜ H and ˜ E). Need other asymmetries on same kinematic bin (or add ≃ 5-10 % systematic uncertainty).

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 10 / 16

SLIDE 33

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

Electron Ion Collider.

Spin observables : both polarized ions and electrons.

Luminosity : ≃ 1034 cm−2.s−1. Configuration : 20 GeV × 250 GeV. 3 months beam time. xB range : 1.6.10−3 → 2.5.10−3. Q2 range : 3.2 → 5.6 GeV2. t range : −1. → −0.05 GeV2.

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 11 / 16

SLIDE 34

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

PROPHET.

Platform for Representing the Organization of Partons inside Hadrons and Experimental Tomographies.

1 Comprehensive database of experimental results. 2 Comprehensive database of theoretical predictions. 3 Fitting engine. 4 Propagation of statistic and systematic uncertainties. 5 Visualizing software to compare experimental results and

model expectations.

6 Connection to experimental set-up descriptions to

design new experiments.

7 Interactive website providing free access to model and

experimental values.

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 12 / 16

SLIDE 35

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

PROPHET.

First components already used in fits or event generators.

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 13 / 16

SLIDE 36

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

PROPHET.

Tentative design of a visualizing software.

Bag model, up quark in unpolarized proton.

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 14 / 16

SLIDE 37

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

PROPHET.

Tentative design of a visualizing software.

Bag model, up quark in transversely polarized proton.

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 14 / 16

SLIDE 38

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

PROPHET.

Tentative design of a visualizing software.

Bag model, down quark in unpolarized proton.

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 14 / 16

SLIDE 39

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

PROPHET.

Tentative design of a visualizing software.

Bag model, down quark in transversely polarized proton.

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 14 / 16

SLIDE 40

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

Conclusions.

Facing very exciting times for GPDs !

Important experimental results during the last decade. Encouraging first results on extraction of GPDs. Several points still need to be clarified :

Universality. Precise impact of subdominant GPDs and their hierarchy.

New facilities will explore new kinematic ranges or provide challenging constraints for phenomenology. Need of a robust and efficient fitting strategy for DVCS and DVMP. First steps in the development of a platform dedicated to global GPD analysis.

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 15 / 16

SLIDE 41

Pivotal year for GPDs 2011 situation

GPDs and DVCS Leading twist, leading order Selected data

Status of GPD analysis

Extraction methods Universality Key results

Future

rientations

COMPASS-II JLab’s 12 GeV upgrade Spin observables

n an EIC

The PROPHET package

Conclusions

Acknowledgments.

F.-X. Girod

S. Goloskokov
P. Guichon
M. Guidal
P. Kroll
K. Kumericki
D. M¨

uller

C. Mu˜

noz Camacho

K. Passek-

Kumericki

K. Semenov
M. Vander-

haeghen

H. Moutarde (Irfu/SPhN, CEA-Saclay)

Hadron 2011 - 14 / 06 / 2011 16 / 16