  Large vorticities in the Quark-Gluon Plasma produced in peripheral collisions
studied by the STAR collaboration at the RHIC facility have been deduced from
observations of polarizations of $\Lambda$ and $\overline{\Lambda}$ hyperons.
Recently, the STAR collaboration has reported on the dependence of these
polarizations on centrality, at impact energy 200 GeV and relatively large
centralities $\mathcal{C} \geq 20\%$. The polarizations increase slowly with
centrality, up to perhaps $\mathcal{C} = \,60 - 70\%$. Here we use a
holographic model of the vortical QGP to make predictions regarding these
polarizations for smaller centralities, ranging from $5 - 20\%$. The model
predicts that as one moves downwards from $20\%$, $\Lambda/\overline{\Lambda}$
polarizations at first decrease but then \emph{increase} sharply, in a
characteristic pattern which should be readily detected if collisions can be
studied at impact energies below 200 GeV and centrality as low as $5 - 10\%$.
The effect should be most evident at moderate impact energies below 200 GeV, so
we give predictions for impact energy 27 GeV.
