  It is widely assumed that the observed reduction of the magnetic field of
millisecond pulsars can be connected to the accretion phase during which the
pulsar is spun up by mass accretion from a companion. A wide variety of
reduction mechanisms have been proposed, including the burial of the field by a
magnetic mountain, formed when the accreted matter is confined to the poles by
the tension of the stellar magnetic field. A magnetic mountain effectively
screens the magnetic dipole moment. On the other hand, observational data
suggests that accreting neutron stars are sources of gravitational waves, and
magnetic mountains are a natural source of a time-dependent quadrupole moment.
We show that the emission is sufficiently strong to be detectable by current
and next generation long-baseline interferometers. Preliminary results from
fully three-dimensional magnetohydrodynamic (MHD) simulations are presented. We
find that the initial axisymmetric state relaxes into a nearly axisymmetric
configuration via toroidal magnetic modes. A substantial quadrupole moment is
still present in the final state, which is stable (in ideal MHD) yet highly
distorted.
