Seminar by Bibiana Prinoth on the topic Titanium in the atmosphere of an exoplanet

This is a talk by Bibiana Prinoth on Titanium in the atmosphere of an exoplanet.

Title: Hidden in plain sight: Using ESPRESSO’s superpower to detect depleted titanium in WASP-121 b

Abstract: Transit spectroscopy has traditionally relied on the integration of multiple transits to achieve the signal-to-noise ratios necessary to resolve atmospheric features. However, only single-transit observations with high signal-to-noise ratio make it possible to disentangle the complex chemistry and dynamics that go beyond global trends by spatially resolving the limbs.

Using ESPRESSO’s superpower—the ability to combine light from all four Unit Telescopes of the Very Large Telescope—we achieved phase-resolved observations of WASP-121 b’s transmission spectrum, uncovering new insights into its atmosphere. These observations revealed the presence of neutral titanium, a species previously thought to be depleted due to cold trapping. Together with vanadium, titanium plays a crucial role in hot gas giant atmospheres, as their oxides are key drivers of temperature inversions. By resolving the planetary velocity traces of titanium and vanadium throughout the transit, we gained a unique glimpse into their local spatial and dynamical distribution, contrasting with predictions from General Circulation Models.

This work underscores the transformative potential of upcoming facilities like the ELT to reveal hidden chemical and dynamical features, paving the way for a new era of atmospheric studies with unprecedented precision.