The Advanced LIGO and Virgo gravitational wave observatories detected a signal on 2019 August 14 during their third observing run, named GW190814. A large number of electromagnetic facilities conducted follow-up campaigns in the search for a possible counterpart to the gravitational wave event, which was made especially promising given the early source classification of a neutron star-black hole merger.We present the results of the GW follow-up campaign taken with the wide-field optical telescope MeerLICHT, located at the South African Astronomical Observatory Sutherland site. We use our results to constrain possible kilonova models. MeerLICHT observed more than 95% of the probability localisation each night for over a week in three optical bands (u,q,i) with our initial observations beginning almost 2 hours after the GW detection. We describe the search for new transients in MeerLICHT data and investigate how our limiting magnitudes can be used to constrain an AT2017gfo-like kilonova. A single new transient was found in our analysis of MeerLICHT data, which we exclude from being the electromagnetic counterpart to GW190814 due to the existence of a spatially unresolved source at the transient's coordinates in archival data. Using our limiting magnitudes, the confidence with which we can exclude the presence of an AT2017gfo-like kilonova at the distance of GW190814 was low (<10−4).
@article{arxiv.2103.02399,
title = {GW190814 follow-up with the optical telescope MeerLICHT},
author = {S. de Wet and P. J. Groot and S. Bloemen and R. Le Poole and M. Klein-Wolt and E. Körding and V. McBride and K. Paterson and D. L. A. Pieterse and P. M. Vreeswijk and P. Woudt},
journal= {arXiv preprint arXiv:2103.02399},
year = {2021}
}