Third Cross-Collserola PhD Meeting in Astrophysics, Cosmology and Particles 2025

AGN outflows in dwarf galaxies using DESI

10 Oct 2025, 12:09

9m

Aula Magna (Institut de Física d'Altes Energies (IFAE))

Talk Morning talks

Speaker

Víctor Rodríguez Morales (Institute of Space Siences (ICE))

Description

Feedback from an active galactic nucleus (AGN) is one of the most important mechanisms in galaxy evolution. This phenomenon is usually found in massive galaxies and is known to regulate star formation. Although dwarf galaxies are assumed to be regulated by supernova feedback, recent studies have offered evidence to support the presence of AGN outflows and feedback in dwarf galaxies.

We investigate the presence of AGN outflows in dwarf galaxies in a sample of 59252 galaxies with outflow signatures drawn from the DESI DR1 survey.

Using the EmFit code, we fit the the different emission lines of the galaxies, and in particular, the [OIII]λ5007 Å emission line. An outflow is usually identified through the detection of a broad component in the [OIII] emission line, which traces gas characterized by non-circular motions.

We find 1599 new dwarf galaxies that present AGN outflow signatures based on the presence of a broad [OIII] emission line. This is the biggest sample of AGN outflows in dwarf galaxies to date, having multiplied the previous sample by more than a factor 10.