Test of Quark-Hadron Duality on Neutron and 3He Spin Structure Functions

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Test of Quark-Hadron Duality on Neutron and 3He
Spin Structure Functions

• Patricia Solvignon
• Temple University
• For the Jlab Hall A Collaboration

Graduate Student Lunch Seminar Jefferson
Lab February 15, 2006
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Inclusive Experiment
Photon virtuality
Invariant mass squared
Bjorken variable

Unpolarized case


Polarized case


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The parton model
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Quark-hadron duality

• First observed by Bloom and Gilman in the 1970s
  on F2
• Scaling curve seen at high Q2 is an accurate
  average over the resonance region at lower Q2

I. Niculescu et al., PRL 85 (2000) 1182
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Quark-hadron duality (contd)
Short distance
Long distance
Wgt2GeV
Wlt2GeV
Asymptotic Freedom
Confinement
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Resonance vs. scaling
Scaling ? Q2 independence of structure function
moments ? resonance region is a part
of the scaling regime
proton
neutron
M. Amerian et al., PRL 859(2002) 242301
R. fatemi et al., PRL 91 (2003) 222002
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World data
Confirmation of duality for the spin-independent
SF

• Jlab Hall C for F2p and F2d

I. Niculescu et al., PRL 85 (2000) 1182
Hint of duality for the spin-dependent SF

• HERMES for A1p
• Jlab Hall B for g1p and g1d
• Jlab Hall A for g13He

A. Airapeian et al., PRL 90 (2003) 092002
Figure from Seonho Choi
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The experiment E01-012
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The parton model