cea dsm dapnia egle tomasi-gustafsson gomel, july 31, 2007 1 polarization observables and hadron...

Egle Tomasi-Gustafsson Gomel July 31 2007CEA DSM Dapnia 1

Polarization Observables and

Hadron Structure (1)

Egle Tomasi-GustafssonSaclay France


MOTIVATIONS

bullIn the traditional view the atomrsquos

nucleus appears as a cluster of nucleons -

protons and neutrons A deeper view

reveals quarks and gluons inside the

nucleons

bullCEBAFrsquos continuous energetic beams of probing electrons let

physicists examine how the two view fit together Ultimately the

process of bridging the views will yield a complete understanding

of nuclear matterhellip

Istitutional plan 2002hellip


GENERAL PLANbullLecture 1

ndash Introduction-Motivationsndash How to measure proton form factorsndash Recent Results

bullLecture 2ndash Consequences

bull Space and time-like regionsbull Asymptoticsbull Two photon exchangebull Radiative corrections

Model Independent StatementsModel Independent Statements


PLANbullIntroduction-MotivationsbullHow to measure form factors

bull Unpolarized method (Rosenbluth separation)

bull Recoil polarization

bull Experiment (Polarimetry)

bullResults


Proton Form FactorsOver a period of time lasting at least 2000 years Man has puzzled over and sought an understanding of the composition of matterhellip

F2F2

F1F1

QQ22=1 GeV=1 GeV22


Hadron Electromagnetic Form factors

ndash Characterize the internal structure of a particle ( point-like)

ndash Elastic form factors contain information on the hadron

ground state

ndash In a P- and T-invariant theory the EM structure of a particle

of spin S is defined by 2S+1 form factors

ndash Neutron and proton form factors are different

ndash Deuteron 2 structure functions but 3 form factors

ndash Playground for theory and experiment


Space-like and time-like regions

bullFFs are analytical functionsbullIn framework of one photon exchange FFs are functions of

the momentum transfer squared of the virtual photon t

ScatterinScatteringg

e- + h =gt e- + h e+ + e- =gt h + h

_

AnnihilationAnnihilation

_

Form factors are real in the space-like region and complex in the time-like region

tlt0 tgt0


How to measure


Electromagnetic interaction

One photon-exchange

bullThe electromagnetic vertex is known (what about radiative corrections )bullThe strong vertex contains the hadron structurebullValidity of one-photon exchange at large t

Observables differential cross section polarization observables


Proton Form Factors before

Rosenbluth separation Polarization observablesRosenbluth separation Polarization observables

Dipole approximation GD=(1+Q2071 GeV2)-2


Dipole Approximation

bullClassical approachndash Nucleon FF (in the Breit

system) are Fourier transform of the charge or magnetic distribution

bullThe dipole approximation corresponds to an exponential density distribution

ndash ρ = ρ0 exp(-rr0)

ndash r02= (024 fm)2 ltr2gt ~(081 fm) 2

m2D =071 GeV2



Dipole Approximation and pQCD

Politzer (1974) Chernyak amp Zhitnisky (1984) Efremov amp Radyuskin (1980) Matveev (1985) Brodsky amp Lepage (1989)

Dimensional scaling

ndash Fn (Q2)= Cn [1( 1+Q2mn) n-1]bull mn=n2 ltquark momentum squaredgtbull n is the number of constituent quarks

ndash Setting 2 =(0471plusmn010) GeV2 (fitting pion data)

bull pion F (Q2)= C [1 (1+Q20471 GeV2)1]

bull nucleon FN (Q2)= CN [1( 1+Q2071 GeV2)2]

bull deuteron Fd (Q2)= Cd [1( 1+Q2141GeV2)5]


PolarizedUnpolarized methods


Rosenbluth separation Rosenbluth separation (1950)(1950)

bullElastic ep cross section (1-γ exchange)

bull point-like particle Mott

Linearity of the reduced cross section


Rosenbluth separationRosenbluth separation

=05=02

=08

Contribution of the electric term

hellipto be compared to the absolute value of the error on and to the size and dependence of RC


The Rosenbluth data (SLAC)The Rosenbluth data (SLAC)

L Andivahis et al Phys Rev D 50 5491 (1994)


The polarization induces a term in the cross section proportional to GE GM

Polarized beam and target or

polarized beam and recoil proton polarization

The polarization method (1967)


The simultaneous measurement of Pt and Pl reduces the systematic errors

The polarization method (exp)


HADRONPOLARIMETRY


Hadron PolarimetryHadron Polarimetry

bullPolarized beams

bullPolarized targets

bullPolarimeters


Hadron Polarimetry

Working principle measurement of the azymuthal asymmetry in a secondary scattering

Large cross section (statistical errors) Large analyzing power (systematic errors)

Vector polarization inclusive scattering on light targets p+C rarr one charged particle +X

Tensor polarization exclusive scattering d+p rarr d+p (elastic scattering) d+p rarr p+p+n (charge exchange reaction)


Charge exchange reactionCharge exchange reaction

Idea from I Pomeranchuk (1938)

d +p rarr (pp) + n The deuteron is a bound np system in T=0 S=1 state ( l=0 or 2)

Selecting a pair of protons in relative s-state requires a spin-flipdue to Pauli principle anti-symmetric total wave function

Large tensor analyzing power


Vector Polarimeter

Inclusive reaction p(d)+C 1 Charged particle+X


Proton polarimeterInclusive reaction p+C 1 Charged particle+X

bull Calibration analyzing powersCalibration analyzing powers

bull Measurement polarizationMeasurement polarization


HADRON POLARIMETRY

bull The Efficiency

bull The Figure of merit

bull The Error on the Polarization Measurement


Polarimetry at 4-5 GeV

Pomme polarimeter

JINR -LHE synchrophasotron


Figure of merit

HYPOM

Analyzing powers


The experimental set-up

bull Trigger on proton background target walls and pion electroproduction

bull The solid angle is defined by the proton


JLab - HALL A


The HALL A-calorimeter

bull Assembled a 135 x 255 m2

calorimeter

bull 17 rows and 9 columns of 15x15 lead-glass blocks

Electron detection


Proton momentum and scattering angle


Identify coincidence events

Good separation peakbackground


Identify elastic events

In-plane and out-of-plane angular correlation

Angles measured in the calorimeter and in the spectrometer



After angular selection


Focal plane polarimeter

cosfpp

nP

yAsinfpp

tP

yA1

2π

)ε(θ)( f

Ptfpp and Pn

fpp are the physical asymmetries at the FPP


Azymuthal distribution

Q2=56 GeVc2


Discussion of the results


THE RESULTS

Jlab E93-027 E99-007SpokepersonsCh Perdrisat V Punjabi M Jones E Brash

M Jones et ql Phys Rev Lett 841398 (2000)O Gayou et al Phys Rev Lett 88092301 (2002)

Linear deviation from dipole

GEpGMp


Nucleon models

bullSkyrme Models (Soliton)bullVector Dominance Models (G-K IJLhellip)bullPerturbative QCDbull(Relativistic) Constituent Quark ModelbullDi-quark modelsbullGPDbullhelliphellip


Comparison with theory


Issues

bullSimultaneous description of the four nucleon form factors

bullin the space-like and in the time-like regionsbullConsequences for the light ions descriptionbullWhen pQCD starts to applybullSource of the discrepancy


The nucleon form factors

VDM IJLF IachelloPLB 43 191 (1973)

Extended VDM (G-K 92) ELLomon PRC 66 045501 2002)

HohlerNPB 114 505 (1976)

BostedPRC 51 409 (1995)

Electric Magneticne

utro

npr

oton

E T-G F Lacroix Ch Duterte GI Gakh EPJA (2005)


The neutron Form Factor


Electric NEUTRON Form Factor

ndash Smaller than for proton but not so smallndash New results also based on polarization

method


The reaction d(eersquon)p - Ax

-The KHARKOV model - Impulse Approximation - Deuteron structure - Kinematics proton spectator - Polarization observables

GI Gakh A P Rekalo E T-G Annals of Physics (2005)



Select the quasi-elastic Kinematics

Large dependence of the asymmetry on GEn

Polarized electron beam polarized target or neutron polarimeter



Neutron electric form factor

Longitudinally polarized electrons polarized target a method similar to the polarization method which takes into account the deuteron structure

Phys Rev C 70 025202 (2004)

Real Amplitudes functionsof W Q2


GEn from e-deuteron elastic scattering

bullGEn gt GEp starting from 2 GeV2

E T-G and M P Rekalo Europhys Lett 55 188 (2001)


The IA deuteron structure



Polarization Observables and Hadron Structure (2)




ndash Introduction-Motivationsndash How to measure proton form factorsndash Recent Results ndash Space and time-like regions




Time-like region


Crossing Symmetry

Scattering and annihilation channels

- Described by the same amplitude

- function of two kinematical variables s and t

p2 rarr ndash p1

k2 rarr ndash k2

- which scan different kinematical regions


The matrix element


The matrix element

Conservation of hadronic and leptonic current


GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)


Time-like observables | GE| 2 and | GM| 2

As in SL region- Dependence on q2 contained in FFs- Even dependence on cos2exchange- No dependence on the sign of FFs- Enhancement of the magnetic term

but TL form factors are complex

A Zichichi S M Berman N Cabibbo R Gatto Il Nuovo Cimento XXIV 170 (1962)B Bilenkii C Giunti V Wataghin Z Phys C 59 475 (1993)G Gakh and ET-G Nucl Phys A761120 (2005)



-The Total Cross Section

Cross section at 900

-The angular asymmetry R

Due to limited statistics no experimental determination of individual FFs in TL region yet GE=GM or GE=0


Time-Like regionTime-Like region

GE=0

GE=GM

GE=GD

E T-G and M P Rekalo Phys Lett B 504 291 (2001)

| GM| 2

Angular Asymmetry


Models in TL region

E T-G F Lacroix C Duterte GI Gakh EPJA 2005

VDM IJLF IachelloPLB43 191 (1973)

Extended VDM (G-K 92) ELLomon PRC66 045501(2002)

lsquoQCD inspiredrsquo

proton

neutron


Spin Observables

Analyzing power A

Double spin observables


Models in TL Region (polarization)

VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz

E T-G F Lacroix C Duterte GI Gakh


Asymptotics


pQCD predictions

bull Scaling laws probability to keep the hadron intact the momentum transfer is equally shared among the constituents

test form factorsbull Helicity conservation

vector interaction between gluons and massless quarks test polarization bservables

bull Reduced nuclear amplitudesintroduce non perturbative correctionsby removing the

complex structure of the nucleontest reduced cross section


Scaling

pQCD F1 1Q4 F2 1Q6 F1 F2 Q2

Corrections logarithmiques


The deuteron (S=1)


The deuteron Cross section

A(Q2)

B(Q2)A(Q2)


The Deuteron Polarization Observables

Jlab E94-018 SpokepersonsB Beise S Kox

D Abbott et ql Phys Rev Lett 845053 (2000)


Reduced deuteron form factors

LAlexa et al PRL 82 1374 (1999) HallA JLab



LAlexa et al PRL 82 1374 (1999) HallA JLabS Platchkov et al NPA 510 740 (1990) ALS SaclayRG Arnold et al PRL 57 174 (1986) Slac


ed-elastic cross sectionA(Q2)

fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)


From ed-elastic cross section

fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD

Large instability for Λ


Phragmegraven-Lindeloumlf theorem

bullAsymptotic properties for analytical functions if f(z) a as z along a straight line and f(z) b as z along another straight line and f(z) is regular and bounded in the angle between then a=b and f(z) a uniformly in the angle

E T-G and G Gakh Eur Phys J A 26 265 (2005)




Applies to NN and NNInteraction (Pomeranchuk theorem )t=0 not a QCD regime

Connection with QCD asymptoticsGM (TL)

GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF

Different results with different

experimental methods

New mechanism


Two-Photon exchangeTwo-Photon exchange

bull1-2 interference is of the order of =e24=1137 (in usual

calculations of radiative corrections one photon is lsquohardrsquo and one is

lsquosoftrsquo)

bullIn the 70rsquos it was shown [J Gunion and L Stodolsky V Franco

FM Lev VN Boitsov L Kondratyuk and VB Kopeliovich R

Blankenbecker and J Gunion] that at large momentum transfer due

to the sharp decrease of the FFs if the momentum is shared between

the two photons the 2contribution can become very large

bullThe 2 amplitude is expected to be mostly imaginary

bullIn this case the 1-2 interference is more important in time-like

region as the Born amplitude is complex


Qualitative estimation of 2Qualitative estimation of 2 exchange exchange

From quark counting rules Fd ~ t-5 and FN~t-2

For t = 4 GeV2

For d 3He 4He 2effect should appear at ~1 GeV2for protons ~ 10 GeV2

q2 q2

For ed elastic scattering



In 1999 MP Rekalo E T-G and D Prout found

a model-independent parametrization of the 2

contribution and applied to ed-elastic scattering data

rarr Discrepancy between the results from

Hall A [LC Alexa et al Phys Rev Lett 82 1374 (1999)]

and

Hall C [D Abbott et al Phys Rev Lett 82 1379 (1999)]

M P Rekalo E T-G and D Prout Phys Rev C60 042202 (1999)


1g

11-2-2 interference interference

21

M P Rekalo E T-G and D Prout Phys Rev C (1999)


Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA


eeplusmn plusmn + p+ prarr rarr eeplusmnplusmn + p+ p

1 exchange

bull Two EM form factorsbull Real (in SL region)bull Functions of one variable (t)bull Describe e+ and e- scattering

2 exchange

bull Three structure functionsbull Complexebull Functions of TWO variables (st)bull Different for e+ and e- scattering

4 spin frac12 fermions rarrrarr 16 amplitudes in the general caseT-invariance of EM interaction identity of initial and final states helicity conservation unitarity


Model independent considerations

Determination of EM form factors in presence of 2exchange

- electron and positron beams - longitudinally polarized - in identical kinematical conditions

Where VEPP3 (Novosibirsk) ( cf S Serednyakov) HERA

Generalization of the polarization method (A Akhiezer and MP Rekalo)


If no positron beamhellip

Either three T-odd polarization observableshellip

bullAy unpolarized leptons transversally polarized target (or Py outgoing nucleon polarization with unpolarized leptons unpolarized target )

bullDepolarization tensor (Dab) dependence of the b-component of the final nucleon polarization on the a-component of the nucleon target with longitudinally polarized leptons




or five T-even polarization observableshellip among dd Px(e) Pz(e) Dxx Dyy Dzz Dxz

very difficult experimentsvery difficult experimentsonly model independent ways (without positron beams)only model independent ways (without positron beams)

M P Rekalo and E T-G Nucl Phys A740 (2004) 271 M P Rekalo and E T-G Nucl Phys A742 (2004) 322


Model independent considerations for eeplusmnplusmn N scattering



If no positron beamhellipEither three T-odd polarization observableshellip

bullAy unpolarized leptons transversally polarized target (or Py outgoing nucleon polarization with unpolarized leptons unpolarized target )bullDepolarization tensor (Dab) dependence of the b-component of the final nucleon polarization on the a-component of the nucleon target with longitudinally polarized leptons


M P Rekalo E T-G EPJA (2004) Nucl Phys A (2003)



Parametrization of 2 for ep elastic scattering

With the correct symmetry properties

or

Q2-dependence

Simple parametrization


From the data

deviation from linearity

ltlt 1

Parametrization of 2-contribution for e+p

E T-G G Gakh Phys Rev C (2005)


The proton magnetic form factorThe proton magnetic form factor

The difference is not at the level of the measured observables but on the slope (derivative)

E Brash et al Phys Rev C65 051001 (2002)

Polarization results induce

15-3 global effect


Radiative Corrections to the dataRadiative Corrections to the data

Slope negative if

- RC can reach 40 on - Declared error ~1- Same correction for GE and GM

- Have a large -dependence- Affect the slope

The slope is negative starting from 2-3 GeV2

el=meas RC

slope


Reduced cross section and RC

Data from L Andivahis et al Phys Rev D50 5491 (1994)

Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC

Slope from P ME T-G G Gakh Phys Rev C (2005)


Experimental correlationExperimental correlation

Two parameters linear fit

Correlation GEp2 ndash GMp

2

100

Depends on and on the size of RC ltCRgt

el=meas RC


Structure Function method

bullSF method applied to QED processes calculation of radiative corrections with precision of 01

bullTakes into account the dynamics of the process

bullFormulated in terms of parton densities (leptons antileptons photons)

bullMany applications to different processes

E A Kuraev and VS Fadin Sov J of Nucl Phys 41 466 (1985)

Electron SF probability to lsquofindrsquo electron in the initial electron with energy fraction x and virtuality up to Q2

Lipatov equations (1975)


Structure Function method (Applications)

- e+e- hadrons( J width) E A KURAEV and VS FADIN Sov J of Nucl Phys 41 466 (1985)

- ep ersquoX (elastic and inelastic scattering)E A KURAEV NP MERENKOV and VS FADIN Sov J of Nucl Phys 471009 (1988)

ndash Decay width of mesons (FSI)E A KURAEV JETP Lett65 127 (1997)

ndash ep ersquop() polarized and unpolarized cases (in progress)Y Bystricky EAKuraev E T-G Phys Rev C 75 015207 (2007)

ndash Compton and double Compton scatteringANIlyichev EA Kuraev VBytev and Y P Peresunko J Exp Theor Phys100 31 (2005)

ndash Radiative corrections for LEP beam (small angle BHABHA scattering)

ABArbuzov EAKuraev et al Phys LettB 399 312 (1997)


Short history (I)

Schwinger corrections to cross section for electron scattering in external field

s=s0(1+d) (1)

Yennie Frauchi Suura cross section of any pure process (without real photon emission) is

zero

Kessler Ericsson Baier Fadin Khoze Y Tsai quasi real electron method Emission of hard photon is described in terms of a convolution of a radiative function with Born cross section (1) Not adequate


Short history (II)

1977 Altarelli Parisi Gribov Lipatov Dokshitzer (DGLAP)Asymptotic freedom evolution equation Collins Factorization theorem

Drell-Yan picture of hard processed in QED application ofQCD ideas to QED radiative corrections in form of structurefunctions and Drell-Yan picture

Leading terms and non leading termsexplicitely taken into account in DGLAP evolutionequations In QED known as Lipatov equations (1975)


Scattered electron energy

All orders of PT needed beyond Mo amp Tsai approximation

Initial state emission

final state emission

Quasi-elastic scattering

3

Y0

Not so smallShift to LOWER Q2


The structure function method

bullElectron detected in a calorimeterbull The cross section is integrated on the scattered electron energy fraction

bullThe cross section

bullThe K-factor includes all non leading contributions


Structure function methodStructure function method


Unpolarized Cross sectionUnpolarized Cross section

Born +dipole FFs(=unpolarized experiment+MoampTsai)

SF (with dipole FFs)SF+2 exchange

Q2=3 GeV2

Q2=5 GeV2 SF change the slope

Q2=1 GeV2

2 exchange very small


Interference of 1 2 exchange

bullExplicit calculation for structureless proton

ndash The contribution is small for unpolarized and polarized ep scattering

ndash Does not contain the enhancement factor L

ndash The relevant contribution to K is ~ 1

EAKuraev V Bytev Yu Bystricky ET-G Phys Rev D74 013003 (2006)


Polarization ratioPolarization ratio

Born SFSF+2 exchange

=60deg

2 destroys linearity


=80deg

=20deg


Correction (SF method)

Polarization data

JLab data

SLAC data

Yu Bystricky EAKuraev E T-G Phys Rev C 75 015207 (2007)


Conclusions and PerspectivesbullFundamental measurement the electric and the

magnetic distributions of the proton are differentbullExtension at larger q2

ndash In SL region

observe a zero of GEp


When GEp =0

0

bullJlab E01-109

ndash approved 072001072004

ndash scheduled 2007

ndash Spokepersons

Ch Perdrisat V Punjabi

M Jones E Brash

ndash 20 Laboratories 80 people

bullHall A =gt Hall CbullNew polarimeter bullNew calorimeter

bullGep IV up to 12 GeV2

after the upgrade of Cebaf




ndash In SL region

observe a zero of GEp ndash In TL region

bull Separation of GE and GM

bull Access their relative phase (polarization)through the angular dependence of differential cross section and polarization observables


FF measurement projected accuracy (Frascati)

Integrated luminosity 700-1000 pb-1

KLOE in last 12 months 1800 pb-1 at mass

prototne

proton neutron


Perspectives in Time-Like region

Frascati

Panda


ConclusionsbullFundamental measurement the electric and the


ndash In SL region



bull Access their relative phase (polarization)

Novosibirsk-VEPP3

through the angular dependence of differential cross section and polarization observables

Coherent description in SL and TL regions

Revise radiative corrections IHEP


MOTIVATIONS

bullIn the traditional view the atomrsquos

nucleus appears as a cluster of nucleons -

protons and neutrons A deeper view

reveals quarks and gluons inside the

nucleons

bullCEBAFrsquos continuous energetic beams of probing electrons let

physicists examine how the two view fit together Ultimately the

process of bridging the views will yield a complete understanding

of nuclear matterhellip

Istitutional plan 2002hellip












bullResults



F2F2

F1F1

QQ22=1 GeV=1 GeV22





ground state











e- + h =gt e- + h e+ + e- =gt h + h

_


_


tlt0 tgt0


How to measure



One photon-exchange














m2D =071 GeV2





Dimensional scaling















=05=02

=08















HADRONPOLARIMETRY



bullPolarized beams


bullPolarimeters


Hadron Polarimetry












Vector Polarimeter







HADRON POLARIMETRY

bull The Efficiency





Pomme polarimeter



Figure of merit

HYPOM

Analyzing powers






JLab - HALL A




calorimeter


Electron detection















cosfpp

nP

yAsinfpp

tP

yA1

2π

)ε(θ)( f

Ptfpp and Pn




Q2=56 GeVc2




THE RESULTS




GEpGMp


Nucleon models





Issues







HohlerNPB 114 505 (1976)

BostedPRC 51 409 (1995)

Electric Magneticne

utro

npr

oton







method














Phys Rev C 70 025202 (2004)


















Time-like region


Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2



The matrix element


The matrix element



GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3















bullResults



F2F2

F1F1

QQ22=1 GeV=1 GeV22





ground state











e- + h =gt e- + h e+ + e- =gt h + h

_


_


tlt0 tgt0


How to measure



One photon-exchange














m2D =071 GeV2





Dimensional scaling















=05=02

=08















HADRONPOLARIMETRY



bullPolarized beams


bullPolarimeters


Hadron Polarimetry












Vector Polarimeter







HADRON POLARIMETRY

bull The Efficiency





Pomme polarimeter



Figure of merit

HYPOM

Analyzing powers






JLab - HALL A




calorimeter


Electron detection















cosfpp

nP

yAsinfpp

tP

yA1

2π

)ε(θ)( f

Ptfpp and Pn




Q2=56 GeVc2




THE RESULTS




GEpGMp


Nucleon models





Issues







HohlerNPB 114 505 (1976)

BostedPRC 51 409 (1995)

Electric Magneticne

utro

npr

oton







method














Phys Rev C 70 025202 (2004)


















Time-like region


Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2



The matrix element


The matrix element



GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3






F2F2

F1F1

QQ22=1 GeV=1 GeV22





ground state











e- + h =gt e- + h e+ + e- =gt h + h

_


_


tlt0 tgt0


How to measure



One photon-exchange














m2D =071 GeV2





Dimensional scaling















=05=02

=08















HADRONPOLARIMETRY



bullPolarized beams


bullPolarimeters


Hadron Polarimetry












Vector Polarimeter







HADRON POLARIMETRY

bull The Efficiency





Pomme polarimeter



Figure of merit

HYPOM

Analyzing powers






JLab - HALL A




calorimeter


Electron detection















cosfpp

nP

yAsinfpp

tP

yA1

2π

)ε(θ)( f

Ptfpp and Pn




Q2=56 GeVc2




THE RESULTS




GEpGMp


Nucleon models





Issues







HohlerNPB 114 505 (1976)

BostedPRC 51 409 (1995)

Electric Magneticne

utro

npr

oton







method














Phys Rev C 70 025202 (2004)


















Time-like region


Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2



The matrix element


The matrix element



GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3








ground state











e- + h =gt e- + h e+ + e- =gt h + h

_


_


tlt0 tgt0


How to measure



One photon-exchange














m2D =071 GeV2





Dimensional scaling















=05=02

=08















HADRONPOLARIMETRY



bullPolarized beams


bullPolarimeters


Hadron Polarimetry












Vector Polarimeter







HADRON POLARIMETRY

bull The Efficiency





Pomme polarimeter



Figure of merit

HYPOM

Analyzing powers






JLab - HALL A




calorimeter


Electron detection















cosfpp

nP

yAsinfpp

tP

yA1

2π

)ε(θ)( f

Ptfpp and Pn




Q2=56 GeVc2




THE RESULTS




GEpGMp


Nucleon models





Issues







HohlerNPB 114 505 (1976)

BostedPRC 51 409 (1995)

Electric Magneticne

utro

npr

oton







method














Phys Rev C 70 025202 (2004)


















Time-like region


Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2



The matrix element


The matrix element



GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3









e- + h =gt e- + h e+ + e- =gt h + h

_


_


tlt0 tgt0


How to measure



One photon-exchange














m2D =071 GeV2





Dimensional scaling















=05=02

=08















HADRONPOLARIMETRY



bullPolarized beams


bullPolarimeters


Hadron Polarimetry












Vector Polarimeter







HADRON POLARIMETRY

bull The Efficiency





Pomme polarimeter



Figure of merit

HYPOM

Analyzing powers






JLab - HALL A




calorimeter


Electron detection















cosfpp

nP

yAsinfpp

tP

yA1

2π

)ε(θ)( f

Ptfpp and Pn




Q2=56 GeVc2




THE RESULTS




GEpGMp


Nucleon models





Issues







HohlerNPB 114 505 (1976)

BostedPRC 51 409 (1995)

Electric Magneticne

utro

npr

oton







method














Phys Rev C 70 025202 (2004)


















Time-like region


Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2



The matrix element


The matrix element



GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3





How to measure



One photon-exchange














m2D =071 GeV2





Dimensional scaling















=05=02

=08















HADRONPOLARIMETRY



bullPolarized beams


bullPolarimeters


Hadron Polarimetry












Vector Polarimeter







HADRON POLARIMETRY

bull The Efficiency





Pomme polarimeter



Figure of merit

HYPOM

Analyzing powers






JLab - HALL A




calorimeter


Electron detection















cosfpp

nP

yAsinfpp

tP

yA1

2π

)ε(θ)( f

Ptfpp and Pn




Q2=56 GeVc2




THE RESULTS




GEpGMp


Nucleon models





Issues







HohlerNPB 114 505 (1976)

BostedPRC 51 409 (1995)

Electric Magneticne

utro

npr

oton







method














Phys Rev C 70 025202 (2004)


















Time-like region


Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2



The matrix element


The matrix element



GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3






One photon-exchange














m2D =071 GeV2





Dimensional scaling















=05=02

=08















HADRONPOLARIMETRY



bullPolarized beams


bullPolarimeters


Hadron Polarimetry












Vector Polarimeter







HADRON POLARIMETRY

bull The Efficiency





Pomme polarimeter



Figure of merit

HYPOM

Analyzing powers






JLab - HALL A




calorimeter


Electron detection















cosfpp

nP

yAsinfpp

tP

yA1

2π

)ε(θ)( f

Ptfpp and Pn




Q2=56 GeVc2




THE RESULTS




GEpGMp


Nucleon models





Issues







HohlerNPB 114 505 (1976)

BostedPRC 51 409 (1995)

Electric Magneticne

utro

npr

oton







method














Phys Rev C 70 025202 (2004)


















Time-like region


Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2



The matrix element


The matrix element



GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3















m2D =071 GeV2





Dimensional scaling















=05=02

=08















HADRONPOLARIMETRY



bullPolarized beams


bullPolarimeters


Hadron Polarimetry












Vector Polarimeter







HADRON POLARIMETRY

bull The Efficiency





Pomme polarimeter



Figure of merit

HYPOM

Analyzing powers






JLab - HALL A




calorimeter


Electron detection















cosfpp

nP

yAsinfpp

tP

yA1

2π

)ε(θ)( f

Ptfpp and Pn




Q2=56 GeVc2




THE RESULTS




GEpGMp


Nucleon models





Issues







HohlerNPB 114 505 (1976)

BostedPRC 51 409 (1995)

Electric Magneticne

utro

npr

oton







method














Phys Rev C 70 025202 (2004)


















Time-like region


Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2



The matrix element


The matrix element



GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3







Dimensional scaling















=05=02

=08















HADRONPOLARIMETRY



bullPolarized beams


bullPolarimeters


Hadron Polarimetry












Vector Polarimeter







HADRON POLARIMETRY

bull The Efficiency





Pomme polarimeter



Figure of merit

HYPOM

Analyzing powers






JLab - HALL A




calorimeter


Electron detection















cosfpp

nP

yAsinfpp

tP

yA1

2π

)ε(θ)( f

Ptfpp and Pn




Q2=56 GeVc2




THE RESULTS




GEpGMp


Nucleon models





Issues







HohlerNPB 114 505 (1976)

BostedPRC 51 409 (1995)

Electric Magneticne

utro

npr

oton







method














Phys Rev C 70 025202 (2004)


















Time-like region


Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2



The matrix element


The matrix element



GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3













=05=02

=08















HADRONPOLARIMETRY



bullPolarized beams


bullPolarimeters


Hadron Polarimetry












Vector Polarimeter







HADRON POLARIMETRY

bull The Efficiency





Pomme polarimeter



Figure of merit

HYPOM

Analyzing powers






JLab - HALL A




calorimeter


Electron detection















cosfpp

nP

yAsinfpp

tP

yA1

2π

)ε(θ)( f

Ptfpp and Pn




Q2=56 GeVc2




THE RESULTS




GEpGMp


Nucleon models





Issues







HohlerNPB 114 505 (1976)

BostedPRC 51 409 (1995)

Electric Magneticne

utro

npr

oton







method














Phys Rev C 70 025202 (2004)


















Time-like region


Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2



The matrix element


The matrix element



GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3
















HADRONPOLARIMETRY



bullPolarized beams


bullPolarimeters


Hadron Polarimetry












Vector Polarimeter







HADRON POLARIMETRY

bull The Efficiency





Pomme polarimeter



Figure of merit

HYPOM

Analyzing powers






JLab - HALL A




calorimeter


Electron detection















cosfpp

nP

yAsinfpp

tP

yA1

2π

)ε(θ)( f

Ptfpp and Pn




Q2=56 GeVc2




THE RESULTS




GEpGMp


Nucleon models





Issues







HohlerNPB 114 505 (1976)

BostedPRC 51 409 (1995)

Electric Magneticne

utro

npr

oton







method














Phys Rev C 70 025202 (2004)


















Time-like region


Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2



The matrix element


The matrix element



GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3






bullPolarized beams


bullPolarimeters


Hadron Polarimetry












Vector Polarimeter







HADRON POLARIMETRY

bull The Efficiency





Pomme polarimeter



Figure of merit

HYPOM

Analyzing powers






JLab - HALL A




calorimeter


Electron detection















cosfpp

nP

yAsinfpp

tP

yA1

2π

)ε(θ)( f

Ptfpp and Pn




Q2=56 GeVc2




THE RESULTS




GEpGMp


Nucleon models





Issues







HohlerNPB 114 505 (1976)

BostedPRC 51 409 (1995)

Electric Magneticne

utro

npr

oton







method














Phys Rev C 70 025202 (2004)


















Time-like region


Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2



The matrix element


The matrix element



GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3





Hadron Polarimetry












Vector Polarimeter







HADRON POLARIMETRY

bull The Efficiency





Pomme polarimeter



Figure of merit

HYPOM

Analyzing powers






JLab - HALL A




calorimeter


Electron detection















cosfpp

nP

yAsinfpp

tP

yA1

2π

)ε(θ)( f

Ptfpp and Pn




Q2=56 GeVc2




THE RESULTS




GEpGMp


Nucleon models





Issues







HohlerNPB 114 505 (1976)

BostedPRC 51 409 (1995)

Electric Magneticne

utro

npr

oton







method














Phys Rev C 70 025202 (2004)


















Time-like region


Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2



The matrix element


The matrix element



GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3











Vector Polarimeter







HADRON POLARIMETRY

bull The Efficiency





Pomme polarimeter



Figure of merit

HYPOM

Analyzing powers






JLab - HALL A




calorimeter


Electron detection















cosfpp

nP

yAsinfpp

tP

yA1

2π

)ε(θ)( f

Ptfpp and Pn




Q2=56 GeVc2




THE RESULTS




GEpGMp


Nucleon models





Issues







HohlerNPB 114 505 (1976)

BostedPRC 51 409 (1995)

Electric Magneticne

utro

npr

oton







method














Phys Rev C 70 025202 (2004)


















Time-like region


Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2



The matrix element


The matrix element



GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3









HADRON POLARIMETRY

bull The Efficiency





Pomme polarimeter



Figure of merit

HYPOM

Analyzing powers






JLab - HALL A




calorimeter


Electron detection















cosfpp

nP

yAsinfpp

tP

yA1

2π

)ε(θ)( f

Ptfpp and Pn




Q2=56 GeVc2




THE RESULTS




GEpGMp


Nucleon models





Issues







HohlerNPB 114 505 (1976)

BostedPRC 51 409 (1995)

Electric Magneticne

utro

npr

oton







method














Phys Rev C 70 025202 (2004)


















Time-like region


Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2



The matrix element


The matrix element



GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3






Pomme polarimeter



Figure of merit

HYPOM

Analyzing powers






JLab - HALL A




calorimeter


Electron detection















cosfpp

nP

yAsinfpp

tP

yA1

2π

)ε(θ)( f

Ptfpp and Pn




Q2=56 GeVc2




THE RESULTS




GEpGMp


Nucleon models





Issues







HohlerNPB 114 505 (1976)

BostedPRC 51 409 (1995)

Electric Magneticne

utro

npr

oton







method














Phys Rev C 70 025202 (2004)


















Time-like region


Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2



The matrix element


The matrix element



GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3





Figure of merit

HYPOM

Analyzing powers






JLab - HALL A




calorimeter


Electron detection















cosfpp

nP

yAsinfpp

tP

yA1

2π

)ε(θ)( f

Ptfpp and Pn




Q2=56 GeVc2




THE RESULTS




GEpGMp


Nucleon models





Issues







HohlerNPB 114 505 (1976)

BostedPRC 51 409 (1995)

Electric Magneticne

utro

npr

oton







method














Phys Rev C 70 025202 (2004)


















Time-like region


Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2



The matrix element


The matrix element



GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3









JLab - HALL A




calorimeter


Electron detection















cosfpp

nP

yAsinfpp

tP

yA1

2π

)ε(θ)( f

Ptfpp and Pn




Q2=56 GeVc2




THE RESULTS




GEpGMp


Nucleon models





Issues







HohlerNPB 114 505 (1976)

BostedPRC 51 409 (1995)

Electric Magneticne

utro

npr

oton







method














Phys Rev C 70 025202 (2004)


















Time-like region


Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2



The matrix element


The matrix element



GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3







calorimeter


Electron detection















cosfpp

nP

yAsinfpp

tP

yA1

2π

)ε(θ)( f

Ptfpp and Pn




Q2=56 GeVc2




THE RESULTS




GEpGMp


Nucleon models





Issues







HohlerNPB 114 505 (1976)

BostedPRC 51 409 (1995)

Electric Magneticne

utro

npr

oton







method














Phys Rev C 70 025202 (2004)


















Time-like region


Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2



The matrix element


The matrix element



GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3


















cosfpp

nP

yAsinfpp

tP

yA1

2π

)ε(θ)( f

Ptfpp and Pn




Q2=56 GeVc2




THE RESULTS




GEpGMp


Nucleon models





Issues







HohlerNPB 114 505 (1976)

BostedPRC 51 409 (1995)

Electric Magneticne

utro

npr

oton







method














Phys Rev C 70 025202 (2004)


















Time-like region


Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2



The matrix element


The matrix element



GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3






Q2=56 GeVc2




THE RESULTS




GEpGMp


Nucleon models





Issues







HohlerNPB 114 505 (1976)

BostedPRC 51 409 (1995)

Electric Magneticne

utro

npr

oton







method














Phys Rev C 70 025202 (2004)


















Time-like region


Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2



The matrix element


The matrix element



GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3







THE RESULTS




GEpGMp


Nucleon models





Issues







HohlerNPB 114 505 (1976)

BostedPRC 51 409 (1995)

Electric Magneticne

utro

npr

oton







method














Phys Rev C 70 025202 (2004)


















Time-like region


Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2



The matrix element


The matrix element



GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3





Nucleon models





Issues







HohlerNPB 114 505 (1976)

BostedPRC 51 409 (1995)

Electric Magneticne

utro

npr

oton







method














Phys Rev C 70 025202 (2004)


















Time-like region


Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2



The matrix element


The matrix element



GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3







Issues







HohlerNPB 114 505 (1976)

BostedPRC 51 409 (1995)

Electric Magneticne

utro

npr

oton







method














Phys Rev C 70 025202 (2004)


















Time-like region


Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2



The matrix element


The matrix element



GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3








HohlerNPB 114 505 (1976)

BostedPRC 51 409 (1995)

Electric Magneticne

utro

npr

oton







method














Phys Rev C 70 025202 (2004)


















Time-like region


Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2



The matrix element


The matrix element



GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3









method














Phys Rev C 70 025202 (2004)


















Time-like region


Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2



The matrix element


The matrix element



GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3

















Phys Rev C 70 025202 (2004)


















Time-like region


Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2



The matrix element


The matrix element



GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3




















Time-like region


Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2



The matrix element


The matrix element



GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3





Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2



The matrix element


The matrix element



GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3





The matrix element


The matrix element



GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3





The matrix element



GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3





GE=GM at threshold

Leptonic current

Hadronic current

At threshold L=0 1

L=0 L=2

GE=GM

(M P Rekalo)














GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3

















GE=0

GE=GM

GE=GD


| GM| 2

Angular Asymmetry


Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3





Models in TL region





proton

neutron


Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3





Spin Observables

Analyzing power A




VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3






VDM IJL

Ext VDM


R

Ay Axx Ayy

Axz

Azz



Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3





Asymptotics


pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3





pQCD predictions







Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3





Scaling




The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3





The deuteron (S=1)



A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3






A(Q2)

B(Q2)A(Q2)













fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3
















fD (Q2)= FD (Q2) (FN (Q2 4) GEp (Q2 4))

fD (Q2)= FD (Q2) G2Ep (Q2 4)

fD (Q2)= FD (Q2) F2N(Q2 4)



fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3






fD (Q2)= FD (Q2) F12(Q24)

fD (Q2)= FD (Q2)(F1(Q24)F2(Q24))

fD(Q2)= FD (Q2) F22(Q24)


Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3





Fitting fD











GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3













GM (SL)

GE (SL)


Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3





Two photon exchange


Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3





Two-photon exchange

Electric proton FF



New mechanism





lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3








lsquosoftrsquo)












For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3







For t = 4 GeV2


q2 q2









and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3











and




1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3





1g


21



Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3





Crossing Symmetry




p2 rarr ndash p1

k2 rarr ndash k2





CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3







CA DA



1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3






1 exchange


2 exchange
































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3

































or

Q2-dependence



From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3





From the data


ltlt 1








15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3









15-3 global effect



Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3






Slope negative if




el=meas RC

slope




Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3







Q2=175 GeV2

Q2=5 GeV2

Q2=325 GeV2

Q2=4 GeV2

Q2=25 GeV2

Q2=7 GeV2

Q2=6 GeV2

With RCWithout RC






2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3








2

100


el=meas RC




















Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3























Short history (I)


s=s0(1+d) (1)


zero



Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3





Short history (II)










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3










3

Y0













Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3















Q2=3 GeV2


Q2=1 GeV2












=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3














=60deg



=80deg

=20deg



Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3






Polarization data

JLab data

SLAC data





ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3







ndash In SL region



When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3





When GEp =0

0

bullJlab E01-109



ndash Spokepersons


M Jones E Brash








ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3







ndash In SL region








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3








prototne

proton neutron



Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3






Frascati

Panda




ndash In SL region




Novosibirsk-VEPP3







ndash In SL region




Novosibirsk-VEPP3




cea dsm dapnia egle tomasi-gustafsson gomel, july 31, 2007 1 polarization observables and hadron...

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