| Name: | Spandan Dash |
| Affiliation: | University of Warwick |
| Conference ID : | ASI2024_204 |
| Title : | Looking above the cloud deck of GJ 3470b |
| Authors : | Spandan Dash 1,2, Matteo Brogi 3, Siddharth Gandhi 1,2,4, Marina Lafarga Magro 1,2, Annabella Meech 5, Aaron Bello-Arufe 6, Peter Wheatley 1,2 |
| Authors Affiliation: | 1 Department of Physics, University of Warwick, Coventry - CV47AL, United Kingdom
2 Centre for Exoplanets and Habitability, University of Warwick, Coventry - CV4 7AL, United Kingdom
3 Department of Physics, University of Turin, Via Pietro Giuria 1, I-10125, Turin, Italy
4 Leiden Observatory, Leiden University, Postbus 9513, 2300 RA Leiden, The Netherlands
5 Department of Physics, University of Oxford, Keble Road, Oxford - OX1 3RH, United Kingdom
6 Jet Propulsion Laboratory, California Institute of Technology, Pasadena - CA 91109, USA |
| Mode of Presentation: | Poster |
| Abstract Category : | Sun, Solar System, Exoplanets, and Astrobiology |
| Abstract : | Characterisation of cooler atmospheres of super-Earths and Neptune sized objects 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 infrared observations of the warm Neptune GJ 3470 b taken over two transits using CARMENES (R ∼ 80400) and look for signatures of H2O in these transits with a custom pipeline fully accounting for the effects of data cleaning on a potential exoplanet signal. We find that our data is able to weakly detect an injected signal equivalent to the best-fit model from previous HST WFC3+Spitzer observations. However, we do not measure any significant detection using the actual observations. Using a Bayesian retrieval tool on the two observed transits to put simultaneous constraints on the VMR abundance of H2O and the cloud top-deck pressure selects for a family of degenerate models. This spans from very high abundance (log10(H2O) = -0.5) and cloud-free models, to super-solar abundances (-2.5log10(P)≥-4.5), and then to slightly super-solar and sub-solar abundances (-4.5log10(P)≥-2.5). This is a broader range compared to, but is also compatible with published results from low resolution at a 1𝜎 level. |
