  High-resolution spectroscopy studies of ultra-hot Jupiters have been key in
our understanding of exoplanet atmospheres. Observing into the atmospheres of
these giant planets allows for direct constraints on their atmospheric
compositions and dynamics while laying the groundwork for new research
regarding their formation and evolution environments. Two of the most
well-studied ultra-hot Jupiters are WASP-76b and WASP-121b, with multiple
detected chemical species and strong signatures of their atmospheric dynamics.
We take a new look at these two exceptional ultra-hot Jupiters by reanalyzing
the transit observations taken with ESPRESSO at the Very Large Telescope and
attempt to detect additional species. To extract the planetary spectra of the
two targets, we corrected for the telluric absorption and removed the stellar
spectrum contributions. We then exploited new synthetic templates that were
specifically designed for ultra-hot Jupiters in combination with the
cross-correlation technique to unveil species that remained undetected by
previous analyses. We add a novel detection of Ba+ to the known atmospheric
compositions of WASP-76b and WASP-121b, the heaviest species detected to date
in any exoplanetary atmosphere, with additional new detections of Co and Sr+
and a tentative detection of Ti+ for WASP-121b. We also confirm the presence of
Ca+, Cr, Fe, H, Li, Mg, Mn, Na, and V on both WASP-76b and WASP-121b, with the
addition of Ca, Fe+, and Ni for the latter. Finally, we also confirm the clear
asymmetric absorption feature of Ca+ on WASP-121b, with an excess absorption at
the bluer wavelengths and an effective planet radius beyond the Roche lobe.
This indicates that the signal may arise from the escape of planetary
atmosphere.
