A phenomenological analysis of the longitudinal structure function at small x and low Q 2
Instituto de Física e Matemática, Universidade Federal de Pelotas, Caixa Postal 354, CEP 96010-090, Pelotas, RS, Brazil
2 UERGS, Engenharia de Bioprocessos e Biotecnologia, Universidade Estadual do Rio Grande do Sul, Bento Gonçalves, RS, Brazil
3 GFPAE, IF-UFRGS, High Energy Physics Phenomenology Group, Caixa Postal 15051, CEP 91501-970, Porto Alegre, RS, Brazil
The longitudinal structure function in deep-inelastic scattering is one of the observables from which the gluon distribution can be unfolded. Consequently, this observable can be used to constrain the QCD dynamics at small x. In this work we compare the predictions of distinct QCD models with the recent experimental results for F L(x,Q 2) at small x and low Q 2 obtained by the H1 Collaboration. We focus mainly on the color dipole approach, selecting those models which include saturation effects. Such models are suitable at this kinematical region and also resum a wide class of higher-twist contributions to the observables. Therefore, we investigate the influence of these corrections to F L in the present region of interest.
© Springer-Verlag, 2004