A Gaia-Enceladus analogue in the EAGLE simulation: insights into the early evolution of the Milky Way

LUCAS BIGNONE; AMINA HELMI; PATRICIA TISSERA

ASTROPHYSICAL JOURNAL

IOP PUBLISHING LTD

Lugar: Londres; Año: 2019

0004-637X

We identify a simulated Milky Way-analogue in the EAGLE suite ofcosmological hydrodynamical simulations. This galaxy not only shares similarglobal properties as the Milky Way, but was specifically selected because itsmerger history resembles that currently known for the Milky Way. In particularwe find that this Milky Way analogue has experienced its last significantmerger (with a stellar mass ratio ~0.2) at z ~1.2. We show that thismerger affected both the dynamical properties of the stars present at the time,contributing to the formation of a thick disk, and also leading to asignificant increase in the star formation rate of the host. This object isthus particularly suitable for understanding the early evolutionary history ofthe Milky Way. It is also an ideal candidate for resimulation with much higherresolution as this would allow addressing a plethora of interesting questionssuch as for example the specific distribution of dark matter near the Sun.