  We classify new physics signals in coherent elastic neutrino-nucleus
scattering (CE$\nu$NS) processes induced by $^8$B solar neutrinos in multi-ton
xenon dark matter (DM) detectors. Our analysis focuses on vector and scalar
interactions in the effective and light mediator limits after considering the
constraints emerging from the recent COHERENT data and neutrino masses. In both
cases we identify a region where measurements of the event spectrum alone
suffice to establish whether the new physics signal is related with vector or
scalar couplings. We identify as well a region where measurements of the recoil
spectrum are required so to establish the nature of the new interaction, and
categorize the spectral features that enable distinguishing the vector from the
scalar case. We demonstrate that measurements of the isospin nature of the new
interaction and thereby removal of isospin related degeneracies are possible by
combining independent measurements from two different detectors. We also
comment on the status of searches for vector and scalar interactions for
on-going multi-ton year xenon experiments.
