OGLE-IV: Fourth Phase of the Optical Gravitational Lensing Experiment

Understand

We present both the technical overview and main science drivers of the fourth phase of the Optical Gravitational Lensing Experiment (hereafter OGLE-IV).

• OGLE-IV is currently one of the largest sky variability surveys worldwide, targeting the densest stellar regions of the sky.
• The survey covers over 3000 square degrees in the sky and monitors regularly over a billion sources.
• The main targets include the inner Galactic Bulge and the Magellanic System.