A search for neutral gas outflows in nearby (U)LIRGs

In the last decade, large surveys drawn a detailed picture of fundamental properties of galaxies increasing our understanding of the formation and evolution of galaxies. Theoretical galaxy-evolution models are able to reproduce the properties of the galaxies (and those of the surrounding intergalactic medium) invoking feedback mechanisms from starbursts or AGN. Outflows regulate star formation and AGN activity, redistributing gas, dust and metals over large scales in the interstellar and intergalactic media (negative feedback) being also considered to be able to undergo vigorous star formation (positive feedback). In this context, the study of these mechanisms across the cosmic time is of critical importance to trace the evolution of galaxies. Multiphase outflows are ubiquitous at any redshift, but their study in nearby galaxies offers the opportunity to study the feedback phenomenon in great detail and, also, in environments similar to that observed at high-z, but with a much higher signal-to-noise and spatial resolution. Nearby Luminous and Ultra-Luminous Infrared Galaxies ((U)LIRGs) are interesting populations to study outflows since they show the most conspicuous cases for outflows in the local Universe and have structural and kinematical properties similar to that found for high-z star forming galaxies.

I will present a search for outflows in a sample of 38 local (U)LIRG systems (51 individual galaxies) observed with VIMOS/VLT and SINFONI/VLT integral field units. These optical and near-IR integral field spectroscopy-observations allow to make a significant step forwards in understanding outflow properties such as their geometry and their connection/feedback with the host galaxy.