My research is currently focused focused on analysing the atmospheres of transiting exoplanets using space-based telescopes such as the Hubble Space Telescope, and preparing for the upcoming James Webb Space Telescope.
Prior to starting my PhD, I spent a year in research at the Center for Astrophysics | Harvard-Smithsonian under the supervision of Dr. James Kirk, working as a part of the LRG-BEASTS project.
The goal of the Low Resolution Ground-Based Exoplanet Atmosphere Survey using Transmission Spectroscopy (LRG-BEASTS, "large beasts") is to provide a large sample of optical transmission spectra of hot Jupiter atmospheres, in order to determine the processes driving aerosol formation and to provide the optical data necessary to place tight constraints on abundances derived from IR data.
I combined three transits of the hot-Saturn WASP-21b to obtain the optical transmission spectrum from 4636-9000Å (Alderson et al., 2020) at an average precision of 197ppm, less than one atmospheric scale height. We were able to detect sodium absorption at greater than 4 sigma confidence, in addition to a steep scattering slope, similar to that of the atmosphere of HD189733b. I worked to rule out stellar activity as the cause of this slope, with atmospheric aerosols being the most likely cause. We found no evidence of potassium absorption, adding WASP-21b to the growing list of planets with only one of the alkali metals present in their atmosphere.
The goal of the Low Resolution Ground-Based Exoplanet Atmosphere Survey using Transmission Spectroscopy (LRG-BEASTS, "large beasts") is to provide a large sample of optical transmission spectra of hot Jupiter atmospheres, in order to determine the processes driving aerosol formation and to provide the optical data necessary to place tight constraints on abundances derived from IR data.
I combined three transits of the hot-Saturn WASP-21b to obtain the optical transmission spectrum from 4636-9000Å (Alderson et al., 2020) at an average precision of 197ppm, less than one atmospheric scale height. We were able to detect sodium absorption at greater than 4 sigma confidence, in addition to a steep scattering slope, similar to that of the atmosphere of HD189733b. I worked to rule out stellar activity as the cause of this slope, with atmospheric aerosols being the most likely cause. We found no evidence of potassium absorption, adding WASP-21b to the growing list of planets with only one of the alkali metals present in their atmosphere.
LRG-BEASTS optical transmission spectrum of WASP-21b with the best fitting atmospheric retrieval model (Alderson et. al 2020)
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HEADER IMAGE CREDIT: NASA, ESA, G. BACON
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