Date:
Tue, 07/01/202512:30-13:30
Title: Destructive stellar collisions in galactic nuclei
Speaker: Shmuel Balberg (The Hebrew University of Jerusalem)
Abstract: The centers of galaxies host both a supermassive black hole (SMBH) and a dense stellar cluster. Physical collisions between stars in such an environment can involve sufficiently high velocities so that the colliding stars are completely destroyed. Destructive collisions (DCs) are therefore inevitable, but at what rate? How do they compare, and possibly compete, with other stellar destruction mechanisms that are unique to galactic nuclei? It appears that stars captured through tidal disruption of binaries by the SMBH hold the key to the DC rate, which should be astrophysically significant, and may even be comparable to that of tidal disruption events (TDEs). Given the total energy, mass and location of DCs, the primary flare that follows them should also be similar to that of TDEs, as streams of the disrupted gas shock each other while flowing toward the central black hole. Some potential differences from TDEs may, however, allow to observationally identify DCs as a separate subclass of bright nuclear transients.
Speaker: Shmuel Balberg (The Hebrew University of Jerusalem)
Abstract: The centers of galaxies host both a supermassive black hole (SMBH) and a dense stellar cluster. Physical collisions between stars in such an environment can involve sufficiently high velocities so that the colliding stars are completely destroyed. Destructive collisions (DCs) are therefore inevitable, but at what rate? How do they compare, and possibly compete, with other stellar destruction mechanisms that are unique to galactic nuclei? It appears that stars captured through tidal disruption of binaries by the SMBH hold the key to the DC rate, which should be astrophysically significant, and may even be comparable to that of tidal disruption events (TDEs). Given the total energy, mass and location of DCs, the primary flare that follows them should also be similar to that of TDEs, as streams of the disrupted gas shock each other while flowing toward the central black hole. Some potential differences from TDEs may, however, allow to observationally identify DCs as a separate subclass of bright nuclear transients.