FIOS: Fabry Perot Instrument for Oxygen Searches in Exoplanet Atmospheres.

The upcoming Extremely Large Telescopes are expected to have enough collecting area to start searching for potential biosignature gases, notably molecular oxygen (O2), in the atmospheres of small planets around nearby stars. Recent simulations have shown that spectral resolutions of 300,000 - 400,000 are optimal to detect O2 in the atmosphere of an earth analog. Typical high resolution spectrographs have resolutions around 100,000. In order to increase detection capabilities, we have developed FIOS, a Fabry Perot interferometer array coupled to a high resolution spectrograph. FIOS can achieve a spectral resolution of 500,000 at the O2 A-band (760 nm). It is optimal for O2 detection, while maintaining a higher throughput compared to instruments with similar spectral resolving power. We describe the instrument concept, a simulation of its sensitivity, and preliminary results from our lab prototype.