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Spin Dependence of Diffractive Vector Meson Production

N. N. Nikolaev
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Abstract

I review the recent progress in the theory of s-channel helicity nonconservation (SCHNC) effects in diffractive DIS. SCHNC in diffractive vector meson production is an unique probe of the spin-orbit coupling and Fermi motion of quarks in vector mesons. Photo- and electroproduction of the $ϕ$ and its radial and angular excitations at Jlab is perfectly posed to probe SCHNC in QCD pomeron exchange. I also discuss the unitarity driven demise of the Burkhardt-Cottingham sum rule and large & scaling departure from the Wandzura-Wilczek relation.

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N. N. Nikolaev. 1999-08-26. Spin Dependence of Diffractive Vector Meson Production. https://arxiv.org/abs/hep-ph/9908453

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