Journal of High Energy Physics (Oct 2022)

Resummation effects in the bottom-quark fragmentation function

  • Fabio Maltoni,
  • Giovanni Ridolfi,
  • Maria Ubiali,
  • Marco Zaro

DOI
https://doi.org/10.1007/JHEP10(2022)027
Journal volume & issue
Vol. 2022, no. 10
pp. 1 – 27

Abstract

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Abstract We compute the perturbative component of the fragmentation function of the b quark to the best of the present theoretical knowledge. The fixed-order calculation to order α s 2 $$ {\alpha}_s^2 $$ of the fragmentation function at the initial scale is matched with soft-emission logarithm resummation to next-to-next-to-leading logarithmic accuracy, so that order- α s 2 $$ {\alpha}_s^2 $$ corrections are accounted for exactly, and logarithmically enhanced contributions from loops of b quarks are included. This requires the calculation of the Mellin transform of the order- α s 2 $$ {\alpha}_s^2 $$ result in the whole complex plane for the Mellin variable, which we provide for the first time for all the fragmenting partons. Evolution is performed to next-to-next-to-leading log accuracy, and mixing with the gluon fragmentation function is taken into account. The perturbative fragmentation functions are made available via LHAPDF grids.

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