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What Have We Learned About and From F_L(x,Q^2) at HERA?

Robert S. Thorne
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Abstract

Recently the H1 collaboration has published a ``determination'' of the structure function F_L(x,Q^2) at low x. I address the question of how reliable this determination really is. I argue that it is in fact a consistency check of a given theoretical approach rather than a real determination of the value of F_L(x,Q^2), but potentially a very useful one. I compare the consistency of different approaches, and indeed find that a LO--in--α_s calculation of structure functions is completely ruled out. I also find that the ``determined'' values of F_L(x,Q^2) are surprisingly stable under changes in theoretical approach but, when working consistently within a well-defined theoretical framework, the values of F_L(x,Q^2) implied are somewhat lower than previously quoted.

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Robert S. Thorne. 1997-08-11. What Have We Learned About and From F_L(x,Q^2) at HERA?. https://doi.org/10.1016/s0370-2693(97)01406-8

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