  The detection of gravitational waves emitted during a neutron star - black
hole merger and the associated electromagnetic counterpart will provide a
wealth of information about stellar evolution nuclear matter, and General
Relativity. While the theoretical framework about neutron star - black hole
binaries formed in isolation is well established, the picture is loosely
constrained for those forming via dynamical interactions. Here, we use N-body
simulations to show that mergers forming in globular and nuclear clusters could
display distinctive marks compared to isolated mergers, namely larger masses,
heavier black holes, and the tendency to have no associated electromagnetic
counterpart. These features could represent a useful tool to interpreting
forthcoming observations. In the Local Universe, gravitational waves emitted
from dynamical mergers could be unravelled by detectors sensitive in the
decihertz frequency band, while those occurring at the distance range of
Andromeda and the Virgo Cluster could be accessible to lower-frequency
detectors like LISA.
