  Pulsar glitches-the sudden spin-up in the rotational frequency of a neutron
star-suggest the existence of an angular-momentum reservoir confined to the
inner crust of the neutron star. Large and regular glitches observed in the
Vela pulsar have originally constrained the fraction of the stellar moment of
inertia that must reside in the solid crust to about 1.4%. However, crustal
entrainment-which until very recently has been ignored-suggests that in order
to account for the Vela glitches, the fraction of the moment of inertia
residing in the crust must increase to about 7%. This indicates that the
required angular momentum reservoir may exceed that which is available in the
crust. We explore the possibility that uncertainties in the equation of state
provide enough flexibility for the construction of models that predict a large
crustal thickness and consequently a large crustal moment of inertia. Given
that analytic results suggest that the crustal moment of inertia is sensitive
to the transition pressure at the crust-core interface, we tune the parameters
of the model to maximize the transition pressure, while still providing an
excellent description of nuclear observables. In this manner we are able to
obtain fractional moments of inertia as large as 7% for neutron stars with
masses below 1.6 solar masses. In particular, we find that if the neutron-skin
thickness of 208Pb falls within the (0.20-0.26) fm range, large enough
transition pressures can be generated to explain the large Vela glitches
without invoking an additional angular-momentum reservoir beyond that confined
to the solid crust. Our results suggest that the crust may be enough.
