Determination of the W-boson mass at hadron colliders

We introduce an observable relevant for the determination
of the W-boson mass mW at hadron colliders. This
observable is defined as an asymmetry around the jacobian
peak of the charged-lepton transverse-momentum distribution
in the charged-current Drell–Yan process. We discuss
the observable’s theoretical prediction, presenting results at
different orders in QCD, and showing its perturbative stability.
Its definition as a single scalar number and its linear
sensitivity to mW allow a clean extraction of the latter and a
straightforward discussion of the associated theoretical systematics:
a perturbative QCD uncertainty of O(±5) MeV on
mW can be established by means of this observable, relying
solely on charged-current Drell–Yan information. Owing to
its relatively inclusive nature, the observable displays desirable
properties also from the experimental viewpoint, especially
for the unfolding of detector effects. We show that a
measurement of this observable can lead to a competitive
experimental error on mW at the LHC.