| Abstract : | Exoplanetary research is on the verge of a profound shift, with the field rapidly advancing toward accurate spectroscopic observations of exoplanet atmospheres. An important factor in understanding exoplanetary atmospheres is the detection of clouds and hazes which can influence atmospheric processes and observed spectra. Clouds and hazes dilute spectral features of chemical species, resulting in a Rayleigh-like scattering slope in UV-optical and a grey-absorbing cloud deck in optical transmission spectra.
Hot-Jupiters that orbit close to their host star can be strongly irradiated and inflated with a high equilibrium temperature, raising the atmospheric scale-height and making it simpler to identify various atmospheric characteristics, making them ideal-targets for transmission spectroscopy for studying various cloud species, hydrocarbon hazes, and volatile species in gas-giant atmospheres.
My research focuses on the clouds, hazes, and volatile species in the atmospheres of a subset of hot-Jupiters by obtaining a transmission spectrum ranging from UV-optical to MIR. This will allow different cloud condensate species to be detected and studied in the context of gas giant atmospheres along with H2O abundance and modal particle size of the cloud-species. However, the composition of the atmosphere varies depending on the physical characteristics of the star and planet (mass, temperature, etc.). For the exoplanets whose Equilibrium temperature <950K, only alkali metals are formed. In contrast, the atmosphere of hot-Jupiters with an equilibrium temperature >950K will be dominated by silicate clouds.
During the gas phase of the protoplanetary disc, the disc is mostly composed of H and He with trance quantities of heavy elements, while during the solid phase, the opposite is true. Determining a hot-Jupiter's metallicity, C/O, and Na/K abundance ratios can provide crucial insights into the hot-Jupiter's structure and evolution mechanism, as well as understanding the formation and occurrence of clouds and hazes. |
