I got involved in research in the field of gravitational waves (GW) with Bence Kocsis shortly after their first observation by LIGO. In Meiron et al. (2017) we examined whether future GW detections may identify triple companions of merging binaries. Such a triple companion causes variations in the GW signal mostly due to the Doppler effect. The research was carried out by producing mock signals of merging compact objects in isolation, and then perturbing them by varying the light travel time in accordance with the motion of the binary around the centre of mass of the triple system. The signal-to-noise ratio in the residual between the perturbed and unperturbed signals was computed (using the advanced LIGO noise curve) to determine whether the perturber would be detectable. We found that the prospects for detecting a triple companion are the highest for low-mass compact object binaries. For example, for merging neutron star binaries, LIGO may detect a white dwarf or M-dwarf perturber if it is within a distance of 0.4 R⊙ from the binary and the system is within a distance of 100 Mpc.
In O’Leary et al. (2016) we performed N-body and Monte Carlo simulations of star clusters to investigate the formation of close pairs of stellar-mass black holes, which eventually merge to produce gravitational waves detectable by LIGO/Virgo and future instruments. We found that it is more likely for two high mass black holes to form a close pair due to dynamical interactions in the cluster. Therefore, it is most likely to detect black hole binaries with a mass close to twice that of the upper bound of stellar black hole masses, and a mass ratio close to unity. We showed that the enhancement of the rate, as a function of the total mass of the binary (as compared to random pairing), is proportional to the mass to the fourth power.