Related papers: Most 1.6 Earth-Radius Planets are not Rocky

Measures of exoplanet bulk densities indicate that small exoplanets with radius less than 3 Earth radii ($R_\oplus$) range from low-density sub-Neptunes containing volatile elements to higher density rocky planets with Earth-like or…

We report on the characterization of the Kepler-101 planetary system, thanks to a combined DE-MCMC analysis of Kepler data and forty radial velocities obtained with the HARPS-N spectrograph. This system was previously validated by Rowe et…

An intriguing trend among \kepler's multi-planet systems is an overabundance of planet pairs with period ratios just wide of a mean motion resonance (MMR) and a dearth of systems just narrow of them. Traditional planet formation models are…

The census of exoplanets is incomplete for orbital distances larger than 1 AU. Here, we present 41 long-period planet candidates in 38 systems identified by Planet Hunters based on Kepler archival data (Q0-Q17). Among them, 17 exhibit only…

By surveying new fields for the shortest-period "big" planets, the Kepler spacecraft could provide the statistics to more clearly measure the occurrence distributions of giant and medium planets. This would allow separate determinations for…

In this thesis, I explore two topics in exoplanet science. The first is the prevalence of Earth-size planets in the Milky Way Galaxy. To determine the occurrence of planets having different sizes, orbital periods, and other properties, I…

We present revised properties for 196,468 stars observed by the NASA Kepler Mission and used in the analysis of Quarter 1-16 (Q1-Q16) data to detect and characterize transiting exoplanets. The catalog is based on a compilation of literature…

The Kepler and K2 missions enabled robust calculations of planet occurrence rates around FGKM-type stars. However, these missions observed too few stars with earlier spectral types to tightly constrain the occurrence rates of planets…

Recent surveys have uncovered an exciting new population of ultra-short-period (USP) planets with orbital periods less than a day. These planets typically have radii <1.5 Earth radii, indicating that they likely have rocky compositions.…

We classified the reddest ($r-J>2.2$) stars observed by the NASA $Kepler$ mission into main sequence dwarf or evolved giant stars and determined the properties of 4216 M dwarfs based on a comparison of available photometry with that of…

Analyses of exoplanet statistics suggest a trend of giant planet occurrence with host star mass, a clue to how planets like Jupiter form. One missing piece of the puzzle is the occurrence around late K dwarf stars (masses of 0.5-0.75Msun…

Previous studies showed evidence of a dearth of close-in exoplanets around fast rotators, which can be explained by the combined action of intense tidal and magnetic interactions between planets and their host star. Detecting more…

We have performed an extensive search for planet candidates in the publicly available Kepler Long Cadence data from quarters Q1 through Q6. The search method consists of initial de-trending of the data, applying the trend filtering…

Extrasolar planets that pass in front of their host star (transit) cause a temporary decrease in the apparent brightness of the star once per orbit, providing a direct measure of the planet's size and orbital period. In some systems with…

In this PhD dissertation, I discuss issues of the Radial Velocities (RV) and transit methods. These techniques allow us to derive the mass and radius of an exoplanet, necessary to model its bulk structure and to have insight on its…

We present precision radial velocity data that reveal a Super-Earth mass planet and two probable additional planets orbiting the bright nearby G0V star HD 1461. Our 12.8 years of Keck HIRES precision radial velocities indicate the presence…

NASA's Kepler Mission uncovered a wealth of planetary systems, many with planets on short-period orbits. These short-period systems reside around 50% of Sun-like stars and are similarly prevalent around M dwarfs. Their formation and…

Kepler-444 is a five planet system around a host-star approximately 11 billion years old. The five transiting planets all have sub-Earth radii and are in a compact configuration with orbital periods between 3 and 10 days. Here we present a…

Models are developed to simulate lightcurves of stars dimmed by transiting exoplanets with and without rings. These models are then applied to \textit{Kepler} photometry to search for planetary rings in a sample of 21 exoplanets, mostly hot…

We present the discovery of the Kepler-19 planetary system, which we first identified from a 9.3-day periodic transit signal in the Kepler photometry. From high-resolution spectroscopy of the star, we find a stellar effective temperature…