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The pion pole in hard exclusive vector-meson leptoproduction

  • S. V. Goloskokov
  • P. KrollEmail author
Regular Article - Theoretical Physics

Abstract

Exploiting a set of generalized parton distributions (GPDs) derived from analyses of hard exclusive leptoproduction of ρ 0, φ and π + mesons, we investigate the ω spin density matrix elements (SDMEs) recently measured by the HERMES Collaboration. It turns out, from our study, that the pion pole is an important contribution to ω production. It will be treated as a one-particle exchange since its evaluation from the GPD \(\tilde E\) considerably underestimates its contribution. As an intermediate step of our analysis, we extract the πω transition form factor for photon virtualities less than 4 GeV2. From our approach we achieve results for the ω SDMEs in good agreement with the HERMES data. The role of the pion pole in exclusive ρ 0 and φ leptoproduction is discussed too.

Keywords

Form Factor Helicity Amplitude Electromagnetic Form Factor Spin Asymmetry Transition Form Factor 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© SIF, Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  1. 1.Bogoliubov Laboratory of Theoretical PhysicsJoint Institute for Nuclear ResearchDubnaMoscow region, Russia
  2. 2.Fachbereich PhysikUniversität WuppertalWuppertalGermany
  3. 3.Institut für Theoretische PhysikUniversität RegensburgRegensburgGermany

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