Heavy-flavor parton distributions without heavy-flavor matching prescriptions

  • Valerio Bertone
  • Alexandre Glazov
  • Alexander Mitov
  • Andrew S. Papanastasiou
  • Maria Ubiali
Open Access
Regular Article - Theoretical Physics


We show that the well-known obstacle for working with the zero-mass variable flavor number scheme, namely, the omission of \( \mathcal{O}(1) \) mass power corrections close to the conventional heavy flavor matching point (HFMP) μ b = m, can be easily overcome. For this it is sufficient to take advantage of the freedom in choosing the position of the HFMP. We demonstrate that by choosing a sufficiently large HFMP, which could be as large as 10 times the mass of the heavy quark, one can achieve the following improvements: 1) above the HFMP the size of missing power corrections \( \mathcal{O}(m) \) is restricted by the value of μ b and, therefore, the error associated with their omission can be made negligible; 2) additional prescriptions for the definition of cross-sections are not required; 3) the resummation accuracy is maintained and 4) contrary to the common lore we find that the discontinuity of α s and pdfs across thresholds leads to improved continuity in predictions for observables. We have considered a large set of proton-proton and electron-proton collider processes, many through NNLO QCD, that demonstrate the broad applicability of our proposal.


Deep Inelastic Scattering (Phenomenology) QCD Phenomenology 


Open Access

This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.


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Copyright information

© The Author(s) 2018

Authors and Affiliations

  1. 1.Department of Physics and AstronomyVU University AmsterdamHV AmsterdamThe Netherlands
  2. 2.Nikhef, Science Park 105XG AmsterdamThe Netherlands
  3. 3.DESY HamburgHamburgGermany
  4. 4.Cavendish LaboratoryUniversity of CambridgeCambridgeU.K.
  5. 5.DAMTPUniversity of CambridgeCambridgeU.K.

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