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arXiv · hep-ph/0002011

Bottom quark electroproduction in variable flavor number schemes

A. Chuvakin·J. Smith·W. L. van Neerven
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Abstract

Two variable flavor number schemes are used to describe bottom quark production in deep inelastic electron-proton scattering. In these schemes the coefficient functions are derived from mass factorization of the heavy quark coefficient functions presented in a fixed flavor number scheme. Also one has to construct a parton density set with five light flavors (u,d,s,c,b) out of a set which only contains four light flavors (u,d,s,c). In order $α_s^2$ the two sets are discontinuous at $μ=m_b$ which follows from mass factorization of the heavy quark coefficient functions when it is carried out in the ${\bar {\rm MS}}$-scheme. Both variable flavor number schemes give almost identical predictions for the bottom structure functions $F_{2,b}$ and $F_{L,b}$. Also they both agree well with the corresponding results based on fixed order four-flavor perturbation theory over a wide range in $x$ and $Q^2$.

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A. Chuvakin, J. Smith, W. L. van Neerven. 2000-02-01. Bottom quark electroproduction in variable flavor number schemes. https://doi.org/10.1103/physrevd.62.036004

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