Andrew Melatos (University of Melbourne)

Gravitational waves from accreting neutron stars - Andrew Melatos colloquium

ATNF Marsfield Lecture Theatre

Abstract

The observational evidence for gravitational wave emission from accreting millisecond pulsars, specifically the spin frequency distribution of the population, is reviewed. These continuous-wave sources are promising candidates for detection by Advanced (and perhaps Intermediate) LIGO. Two theoretical mechanisms are discussed for producing the mass quadrupole moments inferred from the spin frequency data: magnetically confined mountains on the stellar surface (formed by polar magnetic burial) and superfluid circulation in the stellar core (excited by accretion or rotational glitches). Detailed, ab initio numerical simulations of both mechanisms are presented. For magnetic mountains, it is shown that the gravitational wave strain is detectable by LIGO even after ohmic dissipation and three-dimensional hydromagnetic instabilities are considered.