GEPI

De la conception instrumentale
à l’exploitation des observables
Accueil > Seminar on 2021.03.01 by Eduardo (...) > Le vent nous portera...towards a (...)

Le vent nous portera...towards a better understanding of cold gas around galaxies

Max Gronke

Galactic winds are large-scale, multiphase outflows from galaxies and crucial in
order to understand galaxy evolution. They are, for instance, a potent probe for
the underlying feedback mechanisms. The usual picture is that the cold gas has
been accelerated by ram pressure forces due to the hot gas. However, reproducing
this ubiquitous observation in hydrodynamical simulations has proven to be
challenging - simply because the destruction time is shorter than the
acceleration time. During my talk, I will show some analytical estimates and
results from recent (magneto-)hydrodynamics simulations which suggest a solution
to this classical "entrainment problem". I will conclude by discussing potential
observables of cold gas in the surroundings of galaxies. In particular, I want
to show that the Lyman-alpha line is a powerful probe of the (small-scale)
structure of neutral hydrogen.