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On the quark distribution in an on-shell heavy quark and its all-order relations with the perturbative fragmentation function

Einan Gardi
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Abstract

I present new results on the quark distribution in an on-shell heavy quark in perturbative QCD and explore its all-order relations with heavy-quark fragmentation. I first compute the momentum distribution function to all orders in the large-beta_0 limit and show that it is identical to the perturbative heavy-quark fragmentation function in the same approximation. I then analyze the Sudakov limit of the distribution and the fragmentation functions using Wilson lines and prove that the corresponding Sudakov exponents in the non-Abelian theory are the same to any logarithmic accuracy. The anomalous dimension is then determined to two-loop order, corresponding to next-to-next-to-leading logarithmic accuracy in the exponent, in two ways: the first by extracting the singular terms from a recent calculation of the fragmentation function and the second by performing the two-loop Wilson-line calculation in configuration space. I find perfect agreement between the two.

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Einan Gardi. 2005-01-27. On the quark distribution in an on-shell heavy quark and its all-order relations with the perturbative fragmentation function. https://doi.org/10.1088/1126-6708%2F2005%2F02%2F053

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