Magnetosonic waves in the crust of a neutron star

The equations of magnetohydrodynamics are used to show that the energy released at the inner surface of the crust of a neutron star generates magnetosonic wave beams that propagate to the star's surface. These equations can be linearized under the conditions appropriate for the matter in the crust of neutron stars and for the frequency range 107 – 1011 Hz. The solutions describe a beam of standing wave with approximately constant transverse cross-section (radius). The outer base of this beam on the star's surface is a source of radio emission. Electrical currents are excited in this source and it becomes an antenna that emits radio waves into the circumstellar space. The intensity of the radio emission decreases at higher frequencies, so that the spectrum of emitted radiation by pulsars is limited from above (ω ≤ 1011 Hz).