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Few things in the Universe are as dramatic as the death of a star. Transient events like supernovae, gamma ray bursts, and tidal disruptions of stars encountering massive black holes, are all astoundingly bright and carry information about the star that died, how it tore itself apart, and the fragments that remain.

Professor Fong observes short gamma ray bursts to learn about the neutron star and black hole mergers that give rise to these intense explosions.

Professor Miller observes Type Ia supernovae to understand the conditions and environments under which white dwarf stars explode.

The existence of intermediate-mass black holes is one of the most exciting puzzles of modern astronomy. Finding and characterizing intermediate-mass black holes is an important goal of modern astronomy, as it has important implications for nearly every astronomical subfield. For example, in cosmology and galaxy formation, where intermediate-mass black holes could be the seeds for the supermassive black holes observed at the centers of most galaxies.

Professor Fragione studies the multi-messenger signatures of intermediate-mass black holes. By using a combination of high precision simulation-based techniques and semi-analytical methods, he investigates the demographics and properties of intermediate-mass black holes, the energetic transient associated with them, and the detection prospects for present and upcoming gravitational-wave missions, such as LIGO-Virgo and LISA

Over the past several decades, astronomers have begun to take a census of the largest black holes in the Universe and discovered that they are strongly associated with galaxies, and connected to some of the most energetic phenomena known, such as quasars and other active galactic nuclei (AGN).

Professor Larson’s group studies how gravitational wave observations of massive black hole binaries with LISA will elucidate not only the properties of the black holes, but also how they are first seeded and grow in the Universe. They use a variety of approaches, simulating LISA detections and analysis, as well as using modern cosmological simulations, like Illustris, to understand the black hole census of the Universe.

Professor Tchekhovskoy’s group numerically simulates the magneto-hydrodynamics of accretion and jets around massive black holes to model their observational properties and the physical mechanics that connect large structures like jets to the central massive black hole engine that drives them.

Professor Faucher-Giguere’s group studies the connection between massive black holes and galaxy evolution, using both numerical simulation and theoretical analysis to understand how physical processes like star formation, outflows, and feedback from the intergalactic medium influence the co-evolution of the galaxy and black hole together.

Professor Muñoz studies the the orbital evolution of accreting supermassive black hole binaries in galactic nuclei. Using hydrodynamical simulations, he investigates the long-term evolution of binary’s separation and the properties of circumbinary disks.

When stars die, they become either black holes, neutron stars, or white dwarfs. These denizens of the stellar graveyard can hide profound implications about the history of star formation in the galaxy, and continue to influence the evolution of the environments in which they live through dynamical interactions and enrichment of the interstellar medium during their death throes. While they can be dim and difficult to detect with telescopes, they are often excellent sources of gravitational waves.

Professors Kalogera and Larson both use population synthesis to understand the imprint of stellar evolution on the galactic population of stellar remnants and the implications for gravitational wave detection campaigns. Kalogera’s group often focuses on processes related to black holes and neutron stars, while Larson’s group often focuses on white dwarf systems.

Professor Geller uses numerical simulations to study how stellar dynamics within a star cluster shape the population of stellar remnants that can be observed through electromagnetic and gravitational wave telescopes. He also built and maintains the interactive “Mass Plot” for LIGO-Virgo-Kagra.

Professor Muñoz studies the physics of tilted accretion disks around magnetized neutron stars using general-relativistic magnetohydrodynamics simulations.