Description of the spin structure function g_1 at arbitrary $x$ and arbitrary Q^2

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

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arXiv · 0711.4764

Description of the spin structure function g_1 at arbitrary $x$ and arbitrary Q^2

B. I. Ermolaev·M. Greco·S. I. Troyan

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Abstract

The explicit expressions describing the structure function g_1 at arbitrary x and Q^2 are obtained. In the first place, they combine the well-known DGLAP expressions for g_1 with the total resummation of leading logarithms of x, which makes possible to cover the kinematic region of arbitrary x and large Q^2. In order to cover the small-Q^2 region the shift Q^2 -> Q^2 + mu^2 in the large-Q^2 expressions for g_1 is suggested and values of mu are estimated. The expressions obtained do not require singular factors x^{-a} in the fits for initial parton densities.

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B. I. Ermolaev, M. Greco, S. I. Troyan. 2007-11-29. Description of the spin structure function g_1 at arbitrary $x$ and arbitrary Q^2. https://arxiv.org/abs/0711.4764

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