A search for planetary eclipses of white dwarfs in the Pan-STARRS1 medium-deep fields

TL;DR

This study searched for planetary eclipses in white dwarf light curves from Pan-STARRS1, finding no short-duration events but setting strong limits on close-in planet occurrence rates around white dwarfs.

Contribution

The paper provides the first large-scale search for planetary eclipses of white dwarfs in Pan-STARRS1 data and constrains the frequency of close-in planets around white dwarfs.

Findings

No short-duration planetary eclipses detected.

Gas giant planets near the Roche limit are rare (<0.5%).

Habitable-zone super-Earths are less common than around main-sequence stars.

Abstract

We present a search for eclipses of $\sim$1700 white dwarfs in the Pan-STARRS1 medium-deep fields. Candidate eclipse events are selected by identifying low outliers in over 4.3 million light curve measurements. We find no short-duration eclipses consistent with being caused by a planetary size companion. This large dataset enables us to place strong constraints on the close-in planet occurrence rates around white dwarfs for planets as small as 2 R$_\oplus$. Our results indicate that gas giant planets orbiting just outside the Roche limit are rare, occurring around less than 0.5% of white dwarfs. Habitable-zone super-Earths and hot super-Earths are less abundant than similar classes of planets around main-sequence stars. These constraints give important insight into the ultimate fate of the large population of exoplanets orbiting main sequence stars.