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Heavy-quark parton distribution functions and their uncertainties

Z. Sullivan·P. M. Nadolsky
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Abstract

We investigate the uncertainties of the heavy-quark parton distribution functions in the variable flavor number scheme. Because the charm- and bottom-quark parton distribution functions (PDFs) are constructed predominantly from the gluon PDF, it is a common practice to assume that the heavy-quark and gluon uncertainties are the same. We show that this approximation is a reasonable first guess, but it is better for bottom quarks than charm quarks. We calculate the PDF uncertainty for t-channel single-top-quark production using the Hessian matrix method, and predict a cross section of 2.12+0.32-0.29 pb at run II of the Tevatron.

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Z. Sullivan, P. M. Nadolsky. 2001-11-27. Heavy-quark parton distribution functions and their uncertainties. https://arxiv.org/abs/hep-ph/0111358

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