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On determination of the large-${1\over x}$ gluon distribution at HERA

N. N. Nikolaev·B. G. Zakharov
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Abstract

We discuss corrections to the Leading-Log$Q^{2}$ relationships between the gluon density $g(x,Q^{2})$ and $F_{L}(x,Q^{2}),\,\partial F_{T}(x,Q^{2}) /\partial \log Q^{2}$ in the HERA range of large ${1\over x}$. We find that the above quantities probe the gluon density $g(x,Q_{T,L}^{2})$ at $Q_{T,L}^{2}=C_{T,L}Q^{2}$, with the $Q^{2}$-rescaling factors $C_{T}\approx 2.2$ and $C_{L}\approx 0.42$. The possibility of treating charm as an active flavour is critically re-examined.

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N. N. Nikolaev, B. G. Zakharov. 1994-03-12. On determination of the large-${1\over x}$ gluon distribution at HERA. https://doi.org/10.1016/0370-2693(94)90877-x

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