Clouds and hazes are ubiquitous features of exoplanet atmospheres. Their presence can be problematic for exoplanet exploration because they can block the transmission of starlight and mute absorption features in transmission spectra, inhibiting our ability to investigate the atmospheres themselves. One way of overcoming this observational obstacle is to study the light scattered off the planet via the planet’s phase curve.
GJ 1214b, a sub-Neptune located 42 ly away, has a featureless transmission spectrum which may indicate the presence of high-altitude clouds (Kreidberg, 2014). Modeling efforts like those of Morley, et al (2013) have identified KCl and ZnS as candidate cloud species. To identify these species in the planet’s phase curve data, laboratory observations of scattering and polarization phase functions are needed.
Our lab is equipped with a novel instrument, the exoplanet Electrodynamic Balance (exoEDB), for the study of exoplanet cloud particles. In the exoEDB we levitate and optically interrogate single particles for atmospherically relevant timescales (minutes to hours) under temperatures relevant to temperate exoplanets (up to 500K) such as those observed in the upper atmosphere of GJ 1214b. The instrument is novel both in the control it provides over the particle’s temperature environment and its system configuration which enables almost 360° viewing. Because it is so new and little info is available on its performance capabilities, we have worked to characterize the behavior of this instrument and the dynamics of trapped particles. This work plays a key role in our continuing efforts to trap and study exotic cloud species.
In this talk, I will discuss how we characterized the electric field and modeled particle behavior inside the exoEDB and evaluated it against that of the classical Paul trap from which it was derived. Thus far, our results show it performs comparably despite its unorthodox geometry, giving credibility to the instrument's potential as an integral tool for the study of exoplanet clouds.