  Using a Poincar\'e-covariant quark+diquark Faddeev equation and related
symmetry-preserving weak interaction current, we deliver parameter-free
predictions for the nucleon axialvector form factor, $G_A(Q^2)$, on the domain
$0\leq x=Q^2/m_N^2\leq 10$, where $m_N$ is the nucleon mass. We also provide a
detailed analysis of the flavour separation of the proton $G_A$ into
contributions from valence $u$ and $d$ quarks; and with form factors available
on such a large $Q^2$ domain, predictions for the flavour-separated
axial-charge light-front transverse spatial density profiles. Our calculated
axial charge ratio $g_A^d/g_A^u=-0.32(2)$ is consistent with available
experimental data and markedly larger in magnitude than the value typical of
nonrelativistic quark models. The value of this ratio is sensitive to the
strength of axialvector diquark correlations in the Poincar\'e-covariant
nucleon wave function. Working with a realistic axialvector diquark content,
the $d$ and $u$ quark transverse density profiles are similar. Some of these
predictions could potentially be tested with new data on threshold pion
electroproduction from the proton at large $Q^2$.
