5 papers
Analyticity properties of three-point functions in QCD beyond leading order
A. P. Bakulev, A. I. Karanikas, N. G. Stefanis
The removal of unphysical singularities in the perturbatively calculable part of the pion form factor--a classic example of a three-point function in QCD--is discussed. Different `…
Pion form factor analysis using NLO analytic perturbation theory
N. G. Stefanis
I present results for the pion's electromagnetic form factor in the spacelike region, which implement the most advanced perturbative information currently available for this observ…
The gluon content of the and mesons
N. G. Stefanis, S. S. Agaev
We analyze power-suppressed contributions to singlet pseudoscalar and meson transition form factors. These corrections stem from endpoint singularities and help im…
Mapping out the quark structure of hadrons in QCD
Alexander P. Bakulev, S. V. Mikhailov, N. G. Stefanis
In the context of QCD sum rules with non-local condensates we present a pion distribution amplitude, which is double-humped with its end-points x\to(0,1) strongly suppressed, and s…
What is this thing called pion distribution amplitude? From theory to data
Alexander P. Bakulev, S. V. Mikhailov, N. G. Stefanis
We discuss the status of the pion distribution amplitude (DA) from analyzing the CLEO experimental data in the context of QCD sum-rule techniques and QCD perturbation theory at the…