Eur. Phys. J. C (2006) 46: 465-473
https://doi.org/10.1140/epjc/s2006-02523-9

Theoretical Physics

Probing the color glass condensate in an electron-ion collider

¹ Instituto de Física, Universidade de São Paulo, C.P. 66318, 05315-970, São Paulo, SP, Brazil
² High and Medium Energy Group (GAME), Instituto de Física e Matemática, Universidade Federal de Pelotas, C.P. 354, CEP 96010-900, Pelotas, RS, Brazil

^* e-mail: barros@ufpel.edu.br

Received: 15 November 2005
Revised: 17 February 2006
Published online: 30 March 2006

Abstract

Perturbative quantum chromodynamics (pQCD) predicts that the small-x gluons in a hadron wavefunction should form a color glass condensate (CGC), characterized by a saturation scale Q_s(x,A), which is energy and atomic number dependent. In this paper, we study the predictions of CGC physics for electron-ion collisions at high energies. We consider that the nucleus at high energies acts as an amplifier of the physics of high parton densities and estimate the nuclear structure function F₂ ^A(x,Q²), as well as the longitudinal and charm contributions, using a generalization for nuclear targets of the Iancu–Itakura–Munier model that describes the ep HERA data quite well. Moreover, we investigate the behavior of the logarithmic slopes of the total and longitudinal structure functions in the kinematical region of the future electron-ion collider eRHIC.