Motivations

Frascati, June 6, 2005 P. Solvignon, Duality Workshop

Understand transition between partons and hadrons

Study of higher twists

Spin and flavor dependence of quark-hadron duality

Access high xbj region if duality is demonstrated and well understood



Ran in January-February 2003

Inclusive experiment: 3He(e,e’)X

Measured polarized cross-sections differences and asymmetries

Form g1, g2, A1 and A2 for 3He

Test duality on the neutron SSF

Spokepeople: N. Liyanage, J-P. Chen, Seonho ChoiGraduate Student: P. Solvignon


Polarized e- beam at 3, 4 and 5 GeV; Pavg

=(773)%

Both HRS in symmetric config. at 25o and 32o:

Double statistics Control systematics

PID= Cerenkov + EM calo. /e reduced by 104 (e-)>99%

JLab HALL A


LongitudinalLongitudinal and transversetransverse configurations

High luminosity: 1036 s-1 cm-2

2 independent polarimetries: NMR and EPR

Spin exchange between optically pumped Rb and 3He


- -

A//raw = A

raw =

+ +

A//()= //() / 2oborn

oborn = o

raw - 2(N2

/ 3He)N + R.C.

//()raw = 2 A//() o

//() = //()raw + R.C.

Generate asymmetries:

Measure unpolarized cross section:

Form polarized cross sections differences:

Can also get Born asymmetries:


A// A

A1 = - D(1+ ) d(1+ )

(// + tan(/2) )

A// A

A2 = + D(1+ ) d(1+ )

MQ2 E 1g1 = 4e

2 E´ E +E´

MQ22 1g2 = 4e

2 2E´(E +E´)

(- // + E + E´ cos E´sin

)

(D and d depend of R)

Extract g1 and g2 directly from our data

Need external input of R to form A1 and A2

















E01-012 provides precision data of SSF on neutron (3He) for 1.0 < Q2 < 4.0 (GeV/c) 2

Direct extraction of g1 and g2 from our data

Overlap between E01-012 resonance data and DIS test of Quark-hadron duality for neutron

and nuclei SSF

E01-012 data combined with proton data test of spin-flavor dependence of

duality

Our data can also be used to extract moments of SSF (e.g. GDH sum rule, d2, BC sum rule)


Extraction of the neutron SSF

Final results by the end of 2005

Extra slidesExtra slides



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Motivations