Hybrid scheme for heavy flavors: Merging the fixed flavor number scheme and variable flavor number scheme

Parton evolution in the fixed flavor factorization scheme

It is argued that while the scale dependence of the parton distributions in the fixed flavor factorization scheme is governed by three active flavors, the scale dependence of the running coupling should nevertheless be better governed by a variable number of active flavors. The fixed flavor factorization schme (FFS) is characterized by considering the heavy quarks (h = c, b, t) always as extern...

A Variable - Flavour Number Scheme for NNLO

At NNLO it is particularly important to have a Variable-Flavour Number Scheme (VFNS) to deal with heavy quarks because there are major problems with both the zero mass variable-flavour number scheme and the fixed-flavour number scheme. I illustrate these problems and present a general formulation of a Variable-Flavour Number Scheme (VFNS) for heavy quarks that is explicitly implemented up to NN...

The massive 3 - loop operator matrix elements with two masses and the generalized variable flavor number scheme ∗

Inclusive photoproduction of D mesons at next-to-leading order in the General-Mass Variable-Flavor-Number Scheme

We discuss the inclusive production of D mesons in γp collisions at DESY HERA, based on a calculation at next-to-leading order in the general-mass variable-flavornumber scheme. In this approach, MS subtraction is applied in such a way that large logarithmic corrections are resummed in universal parton distribution and fragmentation functions and finite mass terms are taken into account. We pres...

Test Scheme Number

# # # EIG1 PARABOLI MELO Runtimes(s) improv % improv % Case modules nets pins cuts RC cuts RC cuts RC d = 2 d = 10 Table 2: Min-cut and ratio cut (10 ?5) comparisons for MELO bipartitionings versus PARABOLI 15] and EIG1 10] such that each cluster contains at least 45% of the total modules. Missing entries indicate data unavailable. SFC and KP heuristics. Finally, we used MELO orderings to const...