Inroduction

Motivation:

• Observational evidence of activity in the Galactic Center (CG) around several millions ago.
• Unusual star formation in the GC.
• On smaller scales, the existence of massive and young stars in the Central cluster.

It is expected that a large amount of gas is supplied into the center from the Central Molecular Zone (CMZ), a ring-like structure of ~180 pc radius and (5−10)×1e7 Msun

Possible Explanation: Satellite galaxy merge with the Milky way, who perturbs stable gas in the CMZ, driving the gas to inner regions in shorter timescales than natural inflow (Lang et al. 2011).
Expected 1e5 Mʘ infall in 10 Myr.