Neutron star radiation from pulsars is thought to be primarily emitted from regions near their magnetic poles. If the magnetic poles do not coincide with the rotational axis of the neutron star, the emission beam will sweep the sky, and when seen from a distance, if the observer is somewhere in the path of the beam, it will appear as pulses of radiation coming from a fixed point in space (the so-called "lighthouse effect"). The fastest-spinning neutron star known is PSR J1748-2446ad, rotating at a rate of 716 times a second or 43,000 revolutions per minute, giving a linear speed at the
Neutron star towards the plane of curvature. In addition, high energy photons can interact with lower energy photons and the magnetic field for electron-positron pair production, which through electron–positron annihilation leads to further high energy photons. The radiation emanating from the magnetic poles of neutron stars can be described as "magnetospheric radiation", in reference to the magnetosphere of the neutron star. It is not to be confused with "magnetic dipole radiation", which is emitted because the magnetic axis is not aligned with the rotational axis, with a radiation frequency the same as the neutron star's rotational frequency. If the axis of rotation