Towards a precise parton luminosity determination at the CERN LHC

A new approach to determine the Large Hadron Collider (LHC) luminosity is investigated. Instead of employing the proton-proton luminosity measurement, we suggest to measure directly the parton-parton luminosity. It is shown that the electron and muon pseudorapidity distributions, originating from the decay of $W^{+}$, $W^{-}$, and $Z^0$ bosons produced at 14 TeV $\mathrm{pp}$ collisions (CERN LHC), constrain the $x$ distributions of sea and valence quarks and antiquarks in the range from $\approx 3\times {10}^{-4}$ to $\approx {10}^{-1}$ at a $Q^2$ of about ${10}^4$ GeV${}^2$. Furthermore, it is demonstrated that, once the quark and antiquark structure functions are constrained from the $W^{\pm }$ and $Z^0$ production dynamics, other $q\overline{q}$ related scattering processes at the LHC such as $q\overline{q}\to W^{+}{W}^{-}$ can be predicted accurately. Thus, the lepton pseudorapidity distributions provide the key to a precise parton luminosity monitor at the LHC, with accuracies of $\approx \pm 1$% compared to the so far considered goal of $\pm$5%.