Small-x Behaviour of the Non-singlet and Singlet Structure Functions
نویسنده
چکیده
Explicit expressions for the non-singlet and singlet structure functions g1 at the small x-region are obtained. They include the total resummation of doublelogarithmic contributions and accounting for the running QCD coupling effects. We predict that asymptotically the singlet g1 ∼ x−∆S , with the intercept ∆S = 0.86, which is approximately twice larger than the non-singlet intercept ∆NS = 0.4. The impact of the initial quark and gluon densities on the sign of g1 at x ≪ 1 is discussed.
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