SMALL-x BEHAVIOUR OF THE NONSINGLET AND SINGLET STRUCTURE FUNCTIONS g1

Ermolaev B. I., Greco M., Troyan S. I.

Explicit expressions for the nonsinglet and singlet structure functions g1 at the small-x region are obtained. They include the total resummation of double-logarithmic contributions and accounting for the running QCD coupling effects. We predict that asymptotically the singlet g1 ~ x-DS, with the intercept DS = 0.86, which is approximately twice larger than the nonsinglet intercept DNS = 0.4. The impact of the initial quark and gluon densities on the sign of g1 at x<<1 is discussed.

PDF (201 Kb)