A MUlti-wavelength and MUlti-scale approach to constrain the radiative energy from Super-Eddington accretion flows

Objective

The standard theory of accretion breaks down as the the mass-transfer rate increases and the accretion luminosity approaches the classical Eddington limit. At this point, radiation pressure overcomes gravity, and powerful radiatively-driven outflows are launched from the accretion disk. Systems in this regime, such as Tidal Disruption Events, Narrow Line Seyfert 1 galaxies, and Ultraluminous X-ray sources (ULXs), are expected to exert the strongest feedback on the environment due to both the intense radiation field and the aforementioned outflows. This process is also thought to have played a fundamental role in the early growth of supermassive black holes, but many details remain unclear. In particular, while models predict highly anisotropic emission from super-Eddington accretion disks due to the presence of strong outflows enshrouding the inner disk, the energy and angular distribution from these flows has never been measured observationally. Consequently, the radiative feedback from these systems remains largely unknown, precluding an understanding of their capacity to influence their environments and beyond. I propose to provide the first measurements of the energy and angular distribution of the emission in super-Eddington flows using the nearby ULXs and their photo-ionized nebulae as laboratories. What I propose is to employ an innovative approach, whereby using photo-ionization photo-ionization codes, I will simulate nebulae irradiated by anisotropic super-Eddington accretion models derived from a combination of multi-wavelength ULX data, theory and numerical simulations. Then, comparing each photo-ionization simulation with a suite of nebular observations obtained from optical and infrared Integral-Field Unit spectroscopy, I will discriminate between models, testing our understanding of super-Eddington accretion flows from first principles, shedding light on the physics of sustained super-Eddington accretion and its feedback on the environment.