MusE GAs FLOw and Wind (MEGAFLOW)

XI. Scaling relations between outflows and host galaxy properties^⋆

¹ Institut de Recherche en Astrophysique et Planétologie, Université de Toulouse, CNRS, CNES, UPS, 9 Av. du colonel Roche, 31028 Toulouse Cedex 04, France
e-mail: ilane.schroetter@gmail.com
² Centre de Recherche Astrophysique de Lyon (CRAL) UMR5574, Univ Lyon1, Ens de Lyon, CNRS, 69230 Saint-Genis-Laval, France
³ Institut für Physik und Astronomie, Universität Potsdam, Karl-Liebknecht-Str. 24/25, 14476 Golm, Germany
⁴ European Southern Observatory, Karl-Schwarzschild-Str. 2, 85748 Garching, Germany
⁵ Leiden Observatory, Leiden University, PO Box 9513 2300 RA Leiden, The Netherlands
⁶ Institute for Computational Astrophysics and Department of Astronomy & Physics, Saint Mary’s University, 923 Robie Street Halifax, Nova Scotia B3H 3C3, Canada

Received: 24 November 2023
Accepted: 4 April 2024

Abstract

Absorption line spectroscopy using background quasars can provide strong constraints on galactic outflows. In this paper we investigate possible scaling relations between outflow properties, namely outflow velocity V_out, mass ejection rate Ṁ_out, and mass loading factor η, and the host galaxy properties, such as star formation rate (SFR), SFR surface density, redshift, and stellar mass, using galactic outflows probed by background quasars from MEGAFLOW and other surveys. We find that V_out (η) is (anti-)correlated with SFR and SFR surface density. We extend the formalism of momentum-driven outflows from a previous study to show that it applies not only to “down-the-barrel” studies, but also to winds probed by background quasars, suggesting a possible universal wind formalism. Under this formalism, we find a clear distinction between strong and weak outflows where strong outflows seem to have tighter correlations with galaxy properties (SFR or galaxy stellar mass) than weak outflows.