Winds and Feedback from underfed supermassive black holes Ventos e feedback de buracos negros acretando a baixas taxas

• Ano de defesa: 2023
• Autor(a) principal: Almeida, Ivan Carlos de
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: eng
• Instituição de defesa: Biblioteca Digitais de Teses e Dissertações da USP
• Palavras-chave em Português: Buracos negros,discos de acreção; galáxias:Ativas
• Link de acesso: https://www.teses.usp.br/teses/disponiveis/14/14131/tde-03082023-070021/

At the centre of each giant galaxy, there is a supermassive black hole (SMBH). These objects are known to coevolve with their host galaxies and impact their life. The exact effect of the active SMBHs, the so-called active galactic nuclei (AGN), over the galaxy is an open question. In this thesis, we studied the AGN in the local universe --the low-luminosity AGN (LLAGN)-- and how they can produce winds and impact their environment. This thesis is divided into three main works regarding (i) the physics of wind production in the small scales near the SMBH; (ii) the interaction of the outflows with the host galaxy; and (iii) improving how we constrain our models with observations. They cover the different aspects of the same phenomenon: the low-luminosity AGN (LLAGN) activity and their feedback through powerful winds. We estimated in our work the ability of these systems to produce outflows that carry away from the subparsec scales a reasonable amount of energy L_wind ~ 0.01-0.08 dM/dt c^2 -- in physical units ~ 10^(39-40) erg/s. With winds powerful as this, we estimated that SMBHs with M_BH > 10^8 M_sun and dM/dt > 10^(-3) M_Edd can reduce the star formation rate in more than 10% in 10^7yr of activity. In parallel, we also developed the code AGNNES, a new way to calculate an LLAGN spectral energy density using AI with a considerable speed-up.