  This paper is devoted to the semiclassical analysis of the spectrum of the
Dirichlet-Pauli operator on an annulus. We assume that the magnetic field is
strictly positive and radial. We give an explicit asymptotic expansion at the
first order of the lowest eigenvalues of this operator in the semiclassical
limit. In particular, we exhibit the Aharonov-Bohm effect that has been
revealed, for constant magnetic field, in a recent paper by Helffer and
Sundqvist.
