Strong coupling constant from QCD analysis of the fixed-target DIS data

Deep inelastic scattering data on $F_2$ structure function obtained in fixed-target experiments were analyzed in the valence quark approximation with a next-to-next-to-leading-order accuracy. The strong coupling constant is found to be $\alpha_s(M_Z^2) = 0.1157 \pm 0.0022 \text{ (total exp.error)} $, which is seen to be well compatible with the average world value. This study is meant to at least partially explain differences in the predictions for observables at the LHC found recently, caused by usage of various sets of parton distribution functions obtained by different groups.