R. Akhoury et al., POWER CORRECTIONS AND THE GAUSSIAN FORM OF THE MESON WAVE-FUNCTION - ART. NO. 013011, Physical review. D. Particles and fields, 5801(1), 1998, pp. 3011
The wave function of a light pseudoscalar meson is considered and nonp
erturbative corrections as signaled by perturbation theory are calcula
ted. Two schemes are used: the massive gluon and the running coupling
scheme. Both indicate the presence of leading power corrections of O(b
(2)), whose exponentiation leads to a Gaussian dependence of the wave
function on the impact parameter b. The dependence of this correction
on the light cone energy fractions of the quark and the antiquark is d
iscussed and compared with other models for the meson. [S0556-2821(98)
04113-7].