Supermassive black holes (SMBH) and their host galaxies co-evolve, regulating galaxy growth throughout cosmic history. According to standard models of galaxy formation, active galactic nuclei (AGN) feedback may be the key mechanism acting in massive systems (stellar masses > 10¹⁰ M_Sun), primarily through outflows and jets, while supernova feedback likely dominates in the low-mass ones (stellar masses < 10^9.5 M_Sun). However, new observations may question whether this also holds at high redshift. The increasing discovery of AGN in low-mass galaxies suggests that AGN feedback might also play a role in regulating star-formation in this regime. Moreover, the discovery of very bright galaxies in early epochs may require a revision of how feedback is thought of in the early Universe. In the meantime, cosmological simulations have significantly improved in resolution and numerical accuracy, enabling a more precise modeling of the physics of feedback in low- and high- mass galaxies. Despite considerable efforts, simulations and observations still struggle to reach a consensus on the main channels through which stellar and AGN feedback exert their impact, as well as their effects on the galaxy population as a whole.

This special session will explore stellar and AGN feedback at redshift z > 2 and across different galaxy mass regimes. Observational evidence from facilities such as VLT, ALMA, HST, and JWST will be used to explore how feedback impacts star formation and galaxy evolution. Integral field spectroscopic observations will provide insights into feedback mechanisms across different spatial scales, from large-scale outflows to the inner galactic regions.

[Image Credit: NASA, ESA and J. Olmsted (STScI)]

Programme

We will bring together observational and theoretical experts in order to address the following key questions:

• How can we constrain stellar and AGN feedback in galaxies ?
• How does feedback in low-mass galaxies differ from that in more massive ones?
• How does feedback evolve in time, and what role does it play from cosmic noon to dawn?
• What do the latest simulations reveal about feedback across both low-mass and high-mass systems? How can we bridge the gap between simulations and observations with future facilities ?

Invited speakers

• Darshan Kakkad (AGN feedback: observations)
• Sophie Koudmani (stellar and AGN feedback in galaxies from cosmological simulations)

Scientific organisers

• Antonello Calabro' (INAF - Observatory of Rome, IT, co-chair)
• Giustina Vietri (INAF - IASF Milano, IT, co-chair)
• Tiago Costa (Newcastle University, UK)
• Pratika Dayal (Kapteyn Institute at Groningen University, NL)
• Cristina Ramos Almeida (Instituto de Astrofisica de Canarias, ES)
• Aayush Saxena (University of Oxford, UK)

Contact

antonello.calabro @ inaf.it , giustina.vietri @ inaf.it