  Momentum measurements for very high momentum charged particles, such as muons
from electroweak vector boson decays, are particularly susceptible to
charge-dependent curvature biases that arise from misalignments of tracking
detectors. Low momentum charged particles used in alignment procedures have
limited sensitivity to coherent displacements of such detectors, and therefore
are unable to fully constrain these misalignments to the precision necessary
for studies of electroweak physics. Additional approaches are therefore
required to understand and correct for these effects. In this paper the
curvature biases present at the LHCb detector are studied using the pseudomass
method in proton-proton collision data recorded at centre of mass energy
$\sqrt{s}=13$ TeV during 2016, 2017 and 2018. The biases are determined using
$Z\to\mu^+\mu^-$ decays in intervals defined by the data-taking period, magnet
polarity and muon direction. Correcting for these biases, which are typically
at the $10^{-4}$ GeV$^{-1}$ level, improves the $Z\to\mu^+\mu^-$ mass
resolution by roughly 18% and eliminates several pathological trends in the
kinematic-dependence of the mean dimuon invariant mass.
