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arXiv · hep-ph/0211263

Novel hard semiexclusive processes and color singlet clusters in hadrons

L. Frankfurt·M. V. Polyakov·M. Strikman·D. Zhalov·M. Zhalov
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Abstract

Hard scattering to a three cluster final state is suggested as a method to probe configurations in hadrons containing small size color singlet cluster and a residual quark-gluon system of a finite mass. Examples of such processes include $e + N \to e+ p +M_X (Λ+M_X'), p+p \to p+p+M_X(p+Λ+M_X')$ where $M_X(M_X')$ could be a pion(kaon) or other state of finite mass which does not increase with momentum transfer ($Q^2$). We argue that different models of the nucleon may lead to very different qualitative predictions for the spectrum of states $M_X$. We find that in the pion model of nonperturbative $q \bar q$ sea in a nucleon the cross section of these reactions is comparable to the cross section of the corresponding two-body reaction. Studies of these reactions are feasible using both fixed target detectors (EVA at BNL, HERMES at DESY) and collider detectors with a good acceptance in the forward direction.

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L. Frankfurt, M. V. Polyakov, M. Strikman, D. Zhalov, M. Zhalov. 2002-11-16. Novel hard semiexclusive processes and color singlet clusters in hadrons. https://doi.org/10.1142/9789812776211_0049

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