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arXiv · 0711.2830

Moments of the heavy-quark parton distribution function from QCD sum rules

A. G. Oganesian
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Abstract

The moments of the heavy quark-parton distribution functions in a heavy pseudoscalar meson are calculated from QCD sum rules. Expanding these sum rules in the inverse heavy quark mass we obtain the heavy-mass limits of the moments. Comparison with the finite mass results reveals that while the heavy mass expansion works reasonably well for the $b$ quark, one has to take into account terms of higher than $(1/m_c)^2$ order for the $c$ quark. This result can provide a quantitative assessment of $c$ and $b$ quark fragmentation models based on the heavy-quark mass limit.

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A. G. Oganesian. 2007-11-22. Moments of the heavy-quark parton distribution function from QCD sum rules. https://doi.org/10.1134/s1063778809030090

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