Sinking of a magnetically confined mountain on an accreting neutron star

We perform ideal-magnetohydrodynamic axisymmetric simulations of magnetically confined mountains on an accreting neutron star, with masses less than or similar to 0.12 M-circle dot. We consider two scenarios, in which the mountain sits atop a hard surface or sinks into a soft, fluid base. We find that the ellipticity of the star, due to a mountain grown on a hard surface, approaches similar to 2 x 10(-4) for accreted masses greater than or similar to 1.2 x 10(-3) M-circle dot, and that sinking reduces the ellipticity by between 25 and 60 per cent. The consequences for gravitational radiation from low-mass X-ray binaries are discussed.