Gravity seminar - Anthony van Eysden Seminar

Pulsars are ultra-dense remnants of supernova explosions with densities exceeding that of terrestrial nuclei.   Radio waves beamed along their magnetic axis, which is misaligned with the rotation axis, creates a lighthouse effect that is observed at earth as pulsations.  Pulsars exhibit two types of timing irregularity: random fluctuations, or timing noise, and sudden increases in spin frequency, known as glitches, which can both provide a unique opportunity to probe the interior of these exotic objects.  It has been argued that co-rotation between stars crust and interior plasma is established rapidly (within a few seconds) by the magnetic field, which responds via a process analogous to Ekman pumping in a viscous fluid.  However, if the magnetized plasma is considered to be ideal, conservation of energy implies that the final state cannot be co-rotation. Using an exact analytical solution for the coupled motion of the crust and plasma, we demonstrate that the system oscillates persistently and explore the consequences for neutron star observations.