Towards a Precise Parton Luminosity Determination at the CERN LHC

A new approach to determine the 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 bosons produced at 14 TeV pp collisions (LHC), constrain the x distributions of sea and valence quarks and antiquarks in the range from ≈ 3 × 10 to ≈ 10 at a Q of about 10 GeV. Furthermore, it is demonstrated that, once the quark and antiquark structure functions are constrained from the W and Z production dynamics, other qq̄ related scattering processes at the LHC like qq̄ → WW can be predicted accurately. Thus, the lepton pseudorapidity distributions provide the key to a precise parton luminosity monitor at the LHC, with accuracies of ≈ ±1% compared to the so far considered goal of ±5%. submitted to Physical Review D