Two-loop matching conditions for MS parton densities
نویسنده
چکیده
We discuss how the the operator product expansion (OPE) can be used to derive asymptotic expressions for certain integrals. This yields operator matrix elements (OME’s) which determine the matching conditions for MS parton densities across heavy flavour thresholds. Then we construct four and five-flavour densities from a three-flavour set via the evolution of the AP equation using LO and NLO splitting functions.
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