Nonlinear corrections on the parameterization methods

Abstract

We present non-linear corrections (NLC) to the distribution functions at low values of $x$ and $Q^{2}$ using the parametrization $F_{2}(x,Q^{2})$ and $F_{L}(x,Q^{2})$. We use a direct method to extract non-linear corrections to the ratio of structure functions and the reduced cross section in the next-to-next-to-leading order (NNLO) approximation with respect to the parametrization method (PM). Comparison between the non-linear results with the bounds in color dipole model (CDM) and HERA data indicate the consistency of the non-linear behavior of the gluon distribution function at low-$x$ and low-$Q^{2}$. The non-linear longitudinal structure functions are comparable with the H1 Collaboration data in a wide range of $Q^{2}$ values. Consequently, the non-linear corrections at NNLO approximation to the reduced cross sections at low and moderate $Q^{2}$ values show good agreement with the HERA combined data. These results at low $x$ and low $Q^{2}$ can be applied to the LHeC region for analyses of ultra-high-energy processes.