Probing moments of baryon-antibaryon generalized parton distributions at BELLE and FAIR

P. Kroll; A. Schäfer

doi:10.1140/epja/i2014-14001-6

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2024 Impact factor 2.8

Hadrons and Nuclei

Eur. Phys. J. A (2014) 50: 1
https://doi.org/10.1140/epja/i2014-14001-6

Regular Article - Theoretical Physics

Probing moments of baryon-antibaryon generalized parton distributions at BELLE and FAIR

P. Kroll¹^,2^* and A. Schäfer¹

¹ Institut für Theoretische Physik, Universität Regensburg, Regensburg, D-93040, Germany
² Fachbereich Physik, Universität Wuppertal, D-42097, Wuppertal, Germany

^* e-mail: kroll@physik.uni-wuppertal.de

Received: 18 November 2013
Accepted: 23 December 2013
Published online: 20 January 2014

Abstract

We analyze the time-like processes $\gamma\gamma\rightarrow B\overline{B}$ and $p\bar{p}\rightarrow\gamma M$ at large Mandelstam variables within the handbag approach, for which the process amplitudes factorize in hard partonic subprocesses and annihilation form factors. The latter represent moments of baryon-antibaryon generalized parton distributions (GPDs). Symmetry relations restrict the number of independent annihilation form factors for the ground state baryons drastically. We determine these form factors from the present BELLE data on $\gamma\gamma\rightarrow B\overline{B}$ with the help of simplifying assumptions. The knowledge of these form factors allow for predictions of $p\bar{p}\rightarrow\gamma M$ for various mesons which may be probed at FAIR.