Dynamical Parton Distributions for alpha_{S} Determinations

Precise determinations of the strong coupling constant in hadronic collisions demand sets of parton densities spanning a sufficiently wide range of values for the QCD scale parameter Lambda. For such applications, we supplement the recent GRV parametrization by five sets of dynamically generated parton distributions for Lambda-values corresponding to alpha_{S}(M_{Z}^{2}) between 0.104 and 0.122. Present DIS data, including recent small-x HERA results, do not appreciably discriminate between these sets.