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arXiv · 2012.09239

The Influence of Age on the Relative Frequency of Super-Earths and Sub-Neptunes

Angeli Sandoval·Gabriella Contardo·Trevor J. David
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Abstract

There is growing evidence that the population of close-in planets discovered by the Kepler mission was sculpted by atmospheric loss, though the typical timescale for this evolution is not well-constrained. Among a highly complete sample of planet hosts of varying ages the age-dependence of the relative fraction of super-Earth and sub-Neptune detections can be used to constrain the rate at which some small planets lose their atmospheres. Using the California-Kepler Survey (CKS) sample, we find evidence that the ratio of super-Earth to sub-Neptune detections rises monotonically from 1-10 Gyr. Our results are in good agreement with an independent study focused on stars hotter than the Sun, as well as with forward modeling simulations incorporating the effects of photoevaporation and a CKS-like selection function. We find the observed trend persists even after accounting for the effects of completeness or correlations between age and other fundamental parameters.

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Angeli Sandoval, Gabriella Contardo, Trevor J. David. 2021-02-19. The Influence of Age on the Relative Frequency of Super-Earths and Sub-Neptunes. https://doi.org/10.3847/1538-4357%2Fabea9e

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