Looking above the cloud deck of GJ 3470b

Characterisation of cooler atmospheres of super-Earths and Neptune sized objects at low-resolution is often thwarted by the presence of clouds, hazes and aerosols which effectively flatten the transmission spectra. High-Resolution Spectroscopy (HRS) presents an opportunity to overcome this limitation by having the ability to detect molecular species whose spectral line cores extend above the level of clouds in these atmospheres. We analyse High-Resolution observations of the warm Neptune GJ 3470b taken over two transits using CARMENES (R ~ 80400) and look at the possibility of H₂O signatures in these transits. We find that our custom pipeline can provide a detection of H₂O using two transits when they have an injected signal equivalent to the level of what has been observed using HST WFC3 + Spitzer at low resolution. Using a Bayesian retrieval tool on the two observed transits to put simultaneous constraints on the abundance of H₂O and the cloud top-deck pressure suggests a preference for a set of degenerate models with similar variances from the continuum, which is in slight dissonance with published results from low resolution.