On the relevance of chaos in the solar neighbourhood III

MAFFIONE, N. P.; GÓMEZ, F. A.; CINCOTTA , P. M.; GIORDANO, C.M:

La Serena

Congreso; SOCHIAS-AAA bi-national meeting, Septiembre 2018, la Serena, Chile.; 2018

SOCCHIAS - AAA

In order to locally characterize the impact of chaos in the assembling history of our Milky Way (MW), we have beenworking with a combination of cosmological magneto?hydrodynamical simulations (the Auriga suite) and analyticalmodels. The simulations provide us with realistic samples of the stellar component in solar neighbourhood-like volumesas well as values for the structural parameters of MW?type galaxies. The analytical models are calibrated with suchparameter values and used to integrate the initial conditions to compute chaos indicators. In previous works we showedthat using a time?independent representation of a MW?type galaxy consisting of a nuclear region with a supermassiveblack hole, a bulge, an exponential disk and a dark matter halo, chaos might be present (around 20%) but chaoticdiffusion should not be important on erasing local signatures of past galactic accretion events. Our theoretical resultsare currently being validated thanks to the latest observations provided by GAIA. The success of our strategy pushesus to further improve our analytical models. Herein we review previous results and present our new analytical modelthat accounts for the effects of a bar and spiral arms.