Variable Flavor Number Parton Distributions at Next-to-Next-to-Leading Order of QCD

Utilizing recent deep inelastic scattering data and our recent NLO analysis, we present a QCD analysis of the proton in order to determine the parton distributions at next-to-next-to-leading order (NNLO) of QCD. We also study the heavy quark contributions to the proton structure function Fi2(x, Q2), with i = c, b. Our NNLO analysis will be performed within the modified minimal subtraction factorization and renormalization scheme. This analysis is undertake within the framework of the so-called '' zero-mass variable flavor number scheme '' (ZM-VFNS) parton model predictions at high energy colliders where the heavy quarks (c, b, t) considered as massless partons within the nucleon. (authors)