abstract.tex

The joint observation of GW170817 in the electromagnetic (EM) and gravitational wave
(GW) regimes ushered in the era of multimessenger astronomy. Fervent follow up
observations just after the GW trigger revealed the properties of the associated Short
GRB (SGRB) jet and optical kilonova in exquisite detail. Since then, the Advanced LIGO
and VIRGO detectors have detected multiple events in the GW regime, some of which are
neutron star (NS) compact binary coalescences (CBC), wherein at least one of the
components is a neutron star.\\
These systems produce much richer EM outflows when compared to binary black hole (BBH)
systems, since the baryonic matter in the NS can be tidally disrupted which produces a
litany of associated features across the EM spectrum. These features may help shed light
on the behaviour of matter at supranuclear densities and extreme gravity, and also
contain information about the long elusive neutron star Equation of State (EoS).\\ Thus
far, GW170817 has remained the only event for which strong signals have been detected
both in the EM and GW windows. Other events have been detected since using GW, although
their EM observations have been limited to gamma-ray upper limits, presumably due to the
SGRB jets being observed off-axis. Due to this reason, statistical properties of such EM
counterparts remain elusive.\\
Like GW170817 which is believed to be a binary neutron star (BNS) merger, neutron
star-black hole (NSBH) mergers also can launch jets and kilonovae given the right binary
component parameters, as shown in numerical relativity simulations. In this report, a
framework is developed for the computation of the EM counterparts of NS mergers\footnote
{
    N.B.: Codes developed as part of this work can be found at
    \href{https://github.com/BSGalvan/nsbh-codes}{this code repo}.
}
, specifically focusing on outflows from NSBH mergers. This framework computes the
GW network SNR for a given NSBH merger, and also computes the mass left outside the
remnant BH's apparent horizon, the dynamically ejected mass and the mass of the
accretion disc (if one is formed) around the remnant BH. Using this framework, the
detectability of the EM counterparts of NSBH mergers is investigated.