Abstract The Laser Interferometer Space Antenna (LISA) will be a transformative experiment
for gravitational wave astronomy, and, as such, it will offer unique opportunities to address …

We review the current knowledge about nuclear star clusters (NSCs), the spectacularly
dense and massive assemblies of stars found at the centers of most galaxies. Recent …

New kinematic data and modeling efforts in the past few years have substantially expanded
and revised dynamical measurements of black hole masses (M•) at the centers of nearby …

Supermassive black holes (BHs) have been found in 85 galaxies by dynamical modeling of
spatially resolved kinematics. The Hubble Space Telescope revolutionized BH research by …

The Galactic Center is an excellent laboratory for studying phenomena and physical
processes that may be occurring in many other galactic nuclei. The center of our Milky Way …

Massive black holes (BHs) are at once exotic and yet ubiquitous, residing at the centers of
massive galaxies in the local Universe. Recent years have seen remarkable advances in …

We report Atacama Large Millimeter/submillimeter Array (ALMA) observations of CO (3-2)
emission in a sample of seven Seyfert/LINER galaxies at the unprecedented spatial …

We derive improved versions of the relations between supermassive black hole mass (M
BH) and host-galaxy bulge velocity dispersion (σ) and luminosity (L; the M–σ and M–L …

According to the virial theorem, all gravitational systems in equilibrium sit on a plane in the
three-dimensional parameter space defined by their mass, size, and second moment of the …

Since the 1960s, when the connection between quasar energetics and supermassive black
holes was first established, galactic nuclei have remained objects of intense interest to …