Speaker
Description
In this talk I will discuss a novel mechanism to grow supermassive black hole seeds in star-forming ETG progenitors at z >1. This envisages the migration and merging of stellar compact remnants, via gaseous dynamical friction, toward the central regions of such galaxies. I will show that this process can build up central BH masses of order 10^4 − 10^6 Msun in a timescale shorter than 10^8 yr, providing heavy seeds before standard disk accretion takes over to become the dominant process for further BH growth. I will discuss the perspectives to detect the merger events between the migrating stellar remnants and the accumulating central supermassive BH via gravitational wave emission with future ground and space-based detectors such as the Einstein Telescope (ET) and the Laser Interferometer Space Antenna (LISA).