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The Small-x Behaviour of the Singlet Polarized Structure Function g_2 in the Double Logarithmic Approximation

J. Bartels·M. G. Ryskin
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Abstract

The small-x behavior of the singlet contributions to the polarized structure function g_2(x,Q^2) is calculated in the double-logarithmic approximation of perturbative QCD. The dominant contribution is due to the gluons which, in contrast to the unpolarized case, mix with the fermions also in the small-x domain. We find a power-like growth in 1/x in the odd-signature parts of the amplitude with the same power as in the singlet function g_1(x,Q^2) at x<< 1.

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J. Bartels, M. G. Ryskin. 2001-11-23. The Small-x Behaviour of the Singlet Polarized Structure Function g_2 in the Double Logarithmic Approximation. https://doi.org/10.1103/physrevd.65.114012

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