Power corrections to the space-like transition form factorS.S. Agaev1 and N.G. Stefanis2
1 The Abdus Salam International Centre for Theoretical Physics, 34014 Trieste, Italy
2 Institut für Theoretische Physik II, Ruhr-Universität Bochum, 44780 Bochum, Germany
(Received: 19 May 2003 / Revised version: 24 October 2003 / / Published online: 8 December 2003)
Employing the standard hard-scattering approach (HSA) in conjunction with the running coupling (RC) method, the latter joined with the infrared renormalon calculus, we compute power-suppressed corrections to the massless -meson-virtual-gluon transition form factor (FF) . Contributions to the form factor from the quark and gluon components of the meson are taken into account. Analytic expressions for the FFs and are also presented, as well as Borel transforms and resummed expressions. It is shown that except for , the Borel transform contains an infinite number of infrared renormalon poles. It is demonstrated that in the explored range of the total gluon virtuality , power corrections found with the RC method considerably enhance the FF relative to results obtained only in the context of the standard HSA with a "frozen" coupling.
© Società Italiana di Fisica, Springer-Verlag 2004