The Atmospheric Remote-sensing Infrared Exoplanet Large-survey sensitivity and performance

The Ariel space mission will characterise spectroscopically the atmospheres of a large and diverse sample of hundreds of exoplanets. Targets will be chosen to cover a wide range of masses, densities, equilibrium temperatures and host stellar types to study the physical mechanisms behind the observed diversity in the population of known exoplanets. With a 1-m class telescope, Ariel will detect the atmospheric signatures from the small, <100ppm, modulation induced by exoplanets on the bright host-star signals, using transit, eclipse and phase curve spectroscopy. Three photometric and three spectroscopic channels, with Nyquist sampled focal planes, simultaneously cover the 0.5-7.8 micron region of the electromagnetic spectrum, to maximise observing efficiency and to reduce systematics of astrophysical and instrumental origin. This contribution reviews the predicted Ariel performance as well as the design solutions implemented that will allow Ariel to reach the required sensitivity and control of systematics.