https://doi.org/10.1140/epjc/s10052-013-2429-3
Regular Article - Theoretical Physics
Central exclusive production as a probe of the gluonic component of the η′ and η mesons
1
Department of Physics and Institute for Particle Physics Phenomenology, University of Durham, Durham, DH1 3LE, UK
2
Petersburg Nuclear Physics Institute, NRC Kurchatov Institute, Gatchina, St. Petersburg, 188300, Russia
3
Cavendish Laboratory, University of Cambridge, J.J. Thomson Avenue, Cambridge, CB3 0HE, UK
* e-mail: lucian.harland-lang@durham.ac.uk
Received:
21
February
2013
Revised:
12
April
2013
Published online:
15
May
2013
Currently, the long-standing issue concerning the size of the gluonic content of the η′ and η mesons remains unsettled. With this in mind we consider the central exclusive production (CEP) of η′, η meson pairs in the perturbative regime, applying the Durham pQCD-based model of CEP and the ‘hard exclusive’ formalism to evaluate the meson production subprocess. We calculate for the first time the relevant leading order parton-level processes 
and gg→gggg, where the final-state gg and 
pairs form a pseudoscalar flavour-singlet state. We observe that these amplitudes display some non-trivial and interesting theoretical properties, and we comment on their origin. Finally, we present a phenomenological study, and show that the cross sections for the CEP of η′, η meson pairs are strongly sensitive to the size of the gluon content of these mesons. The observation of these processes could therefore provide important and novel insight into this problem.
© Springer-Verlag Berlin Heidelberg and Società Italiana di Fisica, 2013
