  Experiments at the Large Hadron Collider (LHC) have found that the Higgs
boson discovered in 2012 has properties largely consistent with predictions
from the standard model (SM). However, the determination of the couplings of
the Higgs boson to various other SM particles is not very precise, and it is
possible that future experiments with enhanced accuracy may be able to detect
deviations from the SM if any. One category of couplings studied at the LHC is
Higgs flavour-changing couplings to a top-quark and a light-quark ($u$ or $c$)
combination, which vanishes at tree level in the SM, but could be induced by
interactions beyond the SM. Experiments have put a limit on the magnitude of
these couplings, only one coupling assumed nonzero at a time. We investigate
here to what extent the relative magnitudes of the $Hut$ and $Hct$ couplings
and their chirality structure can be determined by means of more detailed
kinematics at a future higher-luminosity version of the LHC in the process of
$tH$ production. In particular, we find that the top-quark polar-angle
distribution in $tH$ production could reveal the relative magnitudes of the
$Hut$ and $Hct$ couplings, while the azimuthal distribution of the charged
leptons arising from top decay can be used for a determination of the chiral
structure of the $Hut$ coupling.
