In this movie we show a simulation of the Arches star cluster evolving from zero age main sequence for 3.5 Myr. It includes gas (SPH) which interacts gravitationally with the stars (Bridge). Both the gas and the stars move within the gravitational potential of the central part of the Galaxy. The stars evolve and affect the gas through stellar wind.

In the top frames, we show an overview of the central region of the galaxy. The turquoise shading represents the Galactic potential, and the yellow points are the stars of the cluster (the gas is not shown in the top panels). Left to right represents 3 views on the 3-dimensional simulation. The bottom panels zoom in on the star cluster, where the colors and sizes indicate the stellar temperature and luminosity in the stellar evolution code. The gas density is indicated by the white-blue shading.

We see that initially the cluster follows a fractal distribution. After a short relaxation, this results in a spherical main cluster with a few separate side-clusters around it. The stellar wind continually blows lower density bubbels in the gas until after approximately 1 Myr most of the gas is expelled from the cluster. During the entire simulation, stars are stripped from the cluster by the Galactic tidal field. Most of these stars end up in a tidal tail behind the cluster.