Related papers: Testing the Metal of Late-Type Kepler Planet Hosts…
The host star metallicity provide a measure of the conditions in protoplanetary disks at the time of planet formation. Using a sample of over 20,000 Kepler stars with spectroscopic metallicities from the LAMOST survey, we explore how the…
We use moderate-resolution spectra of nearby late K and M dwarf stars with parallaxes and interferometrically determined radii to refine their effective temperatures, luminosities, and metallicities. We use these revised values to calibrate…
The NASA K2 mission uses photometry to find planets transiting stars of various types. M dwarfs are of high interest since they host more short period planets than any other type of main sequence stars and transiting planets around M dwarfs…
We constrain the densities of Earth- to Neptune-size planets around very cool (Te =3660-4660K) Kepler stars by comparing 1202 Keck/HIRES radial velocity measurements of 150 nearby stars to a model based on Kepler candidate planet radii and…
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…
The planet-metallicity correlation serves as a potential link between exoplanet systems as we observe them today and the effects of bulk composition on the planet formation process. Many observers have noted a tendency for Jovian planets to…
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…
We present an analysis of three years of precision radial velocity measurements of 160 metal-poor stars observed with HIRES on the Keck 1 telescope. We report on variability and long-term velocity trends for each star in our sample. We…
Knowledge of the metallicities of M dwarfs rests predominantly on the photometric calibration of Bonfils and collaborators, which predicts that M dwarfs in the solar neighborhood, including those with known planets, are systematically…
We present independent and self-consistent metallicities for a sample of 807 planet-hosting stars from the California-Kepler Survey from an LTE spectroscopic analysis using a selected sample of Fe I and Fe II lines. Correlations between…
Recent studies showed that at low metallicities Doppler-detected planet-hosting stars have preferably high alpha-content and belong to the thick disk. We used the reconnaissance spectra of 87 Kepler planet candidates and data available from…
We present an empirical near-infrared (NIR) spectroscopic method for estimating M dwarf metallicities, based on features in the H-band, as well as an implementation of a similar published method in the K-band. We obtained R~2000 NIR spectra…
We present an all-sky catalog of 2970 nearby ($d \lesssim 50$ pc), bright ($J< 9$) M- or late K-type dwarf stars, 86% of which have been confirmed by spectroscopy. This catalog will be useful for searches for Earth-size and possibly…
This work presents a homogeneous derivation of atmospheric parameters and iron abundances for a sample of giant and subgiant stars which host giant planets, as well as a control sample of subgiant stars not known to host giant planets. The…
Previous studies of the interior structure of transiting exoplanets have shown that the heavy element content of gas giants increases with host star metallicity. Since metal-poor planets are less dense and have larger radii than metal-rich…
Reliable detections of Earth-sized planets in the habitable zone remain elusive in the Kepler sample, even for M dwarfs. The Kepler sample was once thought to contain a considerable number of M dwarf stars ($T_\mathrm{eff} < 4000$ K), which…
We examine the correlation between stellar metallicity and short period planets. It appears that approximately 1% of dwarf stars in the solar neighborhood harbor short-period planets characterized by near-circular orbits and orbital periods…
The occurrence rate of hot Jupiters from the Kepler transit survey is roughly half that of radial velocity surveys targeting solar neighborhood stars. One hypothesis to explain this difference is that the two surveys target stars with…
Planet formation is expected to be severely limited in disks of low metallicity, owing to both the small solid mass reservoir and the low opacity accelerating the disk gas dissipation. While previous studies have found a weak correlation…
Based on a carefully constructed sample of dwarf stars, a new optical-near infrared photometric calibration to estimate the metallicity of late-type K and early-to-mid-type M dwarfs is presented. The calibration sample has two parts; the…