  We prove that every subnormal subgroup of p-power index in a right-angled
Artin group is conjugacy p-separable. As an application, we prove that every
right-angled Artin group is conjugacy separable in the class of torsion-free
nilpotent groups. As another application, we prove that the outer automorphism
group of a right-angled Artin group is virtually residually p-finite. We also
prove that the Torelli group of a right-angled group is residually torsion-free
nilpotent, hence residually p-finite and bi-orderable.
