Higher order modes

A GW signal can be decomposed into several modes by a spherical harmonic decomposition. Current searches for GWs use templates that only include the most dominant mode (the quadrupole mode) in matched filtering. Actual GWs however are “full” signals that include higher order multipoles. My work is to investigate the effect of these sub-dominant modes in the detection and parameter estimation of GWs.

The sub-dominant become more important for high mass-ratios, high inclination angles and high total mass. We identified regions in the parameter space (Total mass, mass ratio, spins) of non-precessing Binary Black holes where neglecting the sub-dominant modes is expected to result in significant loss of detection rate and/or significant bias in the estimated parameters of the source.

Here's a quick summary plot. For more information, refer to: arXiv:1612.05608 and arXiv:1409.2349 .