Orbital evolution of the Carina dwarf galaxy and self-consistent star formation history determination

TL;DR

This study models the orbital evolution of the Carina dwarf galaxy using N-body simulations to derive its star formation history and assess past interactions, aligning dynamical and observational data.

Contribution

It introduces a self-consistent method combining orbital dynamics and star formation history derivation for the Carina dwarf galaxy.

Findings

Carina experienced multiple star formation bursts.

Dynamical models align with observational constraints.

Past interaction with Magellanic Clouds is unlikely.

Abstract

We present a new study of the evolution of the Carina dwarf galaxy that includes a simultaneous derivation of its orbit and star formation history. The structure of the galaxy is constrained through orbital parameters derived from the observed distance, proper motions, radial velocity and star formation history. The different orbits admitted by the large proper motion errors are investigated in relation to the tidal force exerted by an external potential representing the Milky Way (MW). Our analysis is performed with the aid of fully consistent N-body simulations that are able to follow the dynamics and the stellar evolution of the dwarf system in order to determine self-consistently the star formation history of Carina. We find a star formation history characterized by several bursts, partially matching the observational expectation. We find also compatible results between dynamical projected quantities and the observational constraints. The possibility of a past interaction between Carina and the Magellanic Clouds is also separately considered and deemed unlikely.