相关论文: Leptoproduction of Heavy Quarks in the Fixed and V…
We compare the results of the fixed-flavor scheme calculation of Laenen, Riemersma, Smith and van Neerven with the variable-flavor scheme calculation of Aivazis, Collins, Olness and Tung for neutral-current (photon-mediated) heavy-flavor…
There are presently two approaches to calculating heavy quark production for the deeply inelastic scattering process in current literature. The conventional fixed-flavor scheme focuses on the flavor creation mechanism and includes the heavy…
A unified QCD formulation of leptoproduction of massive quarks in charged current and neutral current processes is described. This involves adopting consistent factorization and renormalization schemes which encompass both…
Starting from fixed-order perturbation theory (FOPT) we derive expressions for the heavy-flavour components of the deep-inelastic structure functions FL and F2 in the variable-flavour number scheme (VFNS). These expressions are valid in all…
Heavy flavor production is an important QCD process both in its own right and as a key component of precision global QCD analysis. Apparent disagreements between fixed-flavor scheme calculations of b-production rate with experimental…
We present the matching relations of the variable flavor number scheme at next-to-leading order, which are of importance to define heavy quark partonic distributions for the use at high energy colliders such as Tevatron and the LHC. The…
I present a method for calculating heavy quark production which extrapolates smoothly from the well understood limits of the fixed-flavour number scheme for Q^2 approx m_H^2 to the zero-mass scheme at Q^2/m_H^2 -> infinity. For all Q^2 >…
Existing calculations of heavy quark hadroproduction in perturbative QCD are either based on the approximate conventional zero-mass perturbative QCD theory or on next-to-leading order (NLO) fixed-flavor-number (FFN) scheme which is…
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…
Recent accurate data on F_2(x,Q) and on F_2^c(x,Q) from HERA at small-x require a more precise treatment of charm production in the global QCD analysis of parton distributions. We improve on existing global analyses by implementing the…
We compare `fixed flavor number scheme' (FFNS) and `variable flavor number scheme' (VFNS) parton model predictions at high energy colliders. Based on our recent LO- and NLO-FFNS dynamical parton distributions, we generate radiatively two…
We present analytic formulae for the heavy flavour coefficient functions for polarized deep inelastic lepton-hadron scattering. The expressions are valid in the kinematical regime $Q^2\gg m^2$ where $Q^2$ and $m^2$ stand for the masses…
We consider a detailed account on the construction of the heavy-quark parton distribution functions for charm and bottom, starting from $n_f=3$ light flavors in the fixed-flavor number (FFN) scheme and by using the standard decoupling…
In this note we formulate and investigate theoretical uncertainties for high Q^2 deep inelastic heavy quark (charm, etc.) production rates which arise within collinear resummation techniques from variations of the a priori unknown charm…
Open heavy flavour production at $e^+e^-$ colliders in deeply inelastic $e\gamma$ scattering has an interesting feature: the structure function $F_2(x,Q^2)$ for this process is calculable for $x>0.01$, and is essentially proportional to the…
The Thorne-Roberts variable flavour number scheme (VFNS) for heavy quarks is presented in detail for the specific case of charged current DIS. As in neutral current DIS this provides a smooth extrapolation from the fixed flavour number…
Data for D*(2010) meson electroproduction in the range 10 < Q2 < 1350 GeV^2 has recently been presented by the ZEUS collaboration at HERA. We use these results together with previously published data for Q2 > 1 GeV^2 to test whether one can…
We present our QCD analysis of the proton structure function $F_2^p(x,Q^2)$ to determine the parton distributions at the next-to-leading order (NLO). The heavy quark contributions to $F_2^i(x,Q^2)$, with $i$ = $c$, $b$ have been included in…
We compare different schemes for the treatment of heavy quark production in Deep-Inelastic Scattering (DIS). For fully-integrated quantities such as $F_{2}(x,Q^{2})$, we advocate the use of the General-Massive Variable-Flavor-Number…
The most important part of the order $\alpha_s^2$ corrections to the charm component of the charged-current structure functions $F_2(x,Q^2)$ and $F_3(x,Q^2)$ have been calculated. This calculation is based on the asymptotic form of the…