The Detectability of Exo-Earths and Super-Earths Via Resonant Signatures in Exozodiacal Clouds
First Author:
Christopher Stark
Email: starkc AT umd.edu
University of Maryland/NASA Goddard Space Flight Center
NASA GSFC, Exoplanets and Stellar Astrophysics Laboratory
Code 667
Greenbelt, MD 20771 USA
Abstract
Directly imaging extrasolar terrestrial planets necessarily means contending with the astrophysical noise of exozodiacal dust and the circumstellar resonant structures created by extrasolar planets in exozodiacal clouds. Using a custom tailored hybrid symplectic integrator we have constructed 120 models of resonant structures created by exo-Earths and super-Earths on circular orbits interacting with collisionless steady-state dust clouds around a Sun-like star. Our models include enough particles to overcome the limitations of previous simulations that were often dominated by a handful of long-lived particles, allowing us to quantitatively study the contrast of the resulting ring structures. We used these models to estimate the mass of the lowest-mass planet that can be detected through observations of a resonant ring for a variety of assumptions about the dust cloud and the planet's orbit. Our simulations suggest that planets with mass as small as a few times Mars' mass may produce detectable signatures in debris disks at circumstellar distances greater than 10 AU.
