Small- x behavior of the structure function F 2 and its slope ? ln F 2 / ? ln ( 1 / x ) for frozen

Abstract Using the leading-twist approximation of the Wilson operator product expansion with “frozen” and analytic versions of the strong-coupling constant, we show that the Bessel-inspired behavior of the structure function F 2 and its slope ∂ ln F 2 / ∂ ln ( 1 / x ) at small values of x , obtained for a flat initial condition in the DGLAP evolution equations, leads to good agreement with experimental data of deep-inelastic scattering at DESY HERA.