MG11 
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Gravitational Radiation from X-Ray Millisecond Pulsars

Observed spin frequency distribution of the fastest rotating neutron stars suggests that these objects are sources of gravitational waves: One possible mechanism to create a time-dependent quadrupole moment and therefore gravitational radiation is the formation of polar magnetic mountains. Such mountains are created when accreted material is confined at the poles by the magnetic tension of the stellar field. It is also widely believed 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. A wide variety of reduction mechanisms have been proposed, including burial of the stellar field by magnetic mountains. In this talk, we will describe how to self-consistently model magnetic mountains and give a proof of their stability. The mountains effectively screen the magnetic dipole moment, reducing it by 90% after 10^-4 Msun have been added, and produce an associated reduced mass quadrupole moment of ~5x10^37 g cm^2 which is the correct size to explain the observed spin distribution. We will discuss the predicted spectrum of gravitational waves as well as the prospect of their detection with the new generation of long baseline interferometers. Finally, we will discuss the next step in these calculations, such as 3d non-ideal MHD simulations including sinking of the mountains, with the goal of a more accurate prediction of the gravitational wave signal.