arXiv subjects

A. Psaker

Publications and source records attributed to A. Psaker.

3 recordsLinked to original sources

arXiv2011

Observation of quark-hadron duality in gamma*-p helicity cross sections

Combining data on unpolarized and polarized inclusive proton structure functions, we perform the first detailed study of quark-hadron duality in individual helicity-1/2 and 3/2 virtual photoproduction cross sections. We find that duality is realized more clearly in the helicity-1/2 channel, with duality violating corrections < 10% over the entire nucleon resonance region, while larger, < 20% corrections are found in the helicity-3/2 sector. The results are in general agreement with quark model expectations, and suggest that data above the Delta resonance region may be used to constrain both spin-averaged and spin-dependent parton distributions.

nucl-th↗

arXiv2008

Quark-hadron duality and truncated moments of nucleon structure functions

We employ a novel new approach to study local quark-hadron duality using "truncated" moments, or integrals of structure functions over restricted regions of x, to determine the degree to which individual resonance regions are dominated by leading twist. Because truncated moments obey the same Q^2 evolution equations as the leading twist parton distributions, this approach makes possible for the first time a description of resonance region data and the phenomenon of quark-hadron duality directly from QCD.

nucl-th↗

arXiv2006

Weak Deeply Virtual Compton Scattering

We extend the analysis of the deeply virtual Compton scattering process to the weak interaction sector in the generalized Bjorken limit. The virtual Compton scattering amplitudes for the weak neutral and charged currents are calculated at the leading twist within the framework of the nonlocal light-cone expansion via coordinate space QCD string operators. Using a simple model, we estimate cross sections for neutrino scattering off the nucleon, relevant for future high intensity neutrino beam facilities.

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