Bibcode
Wilson, R. F.; Teske, Johanna; Majewski, Steven R.; Cunha, Katia; Smith, Verne; Souto, Diogo; Bender, Chad; Mahadevan, Suvrath; Troup, Nicholas; Allende Prieto, C.; Stassun, Keivan G.; Skrutskie, Michael; ALMEIDA, ANDRES; Brinkmann, Jonathan; APOGEE
Referencia bibliográfica
American Astronomical Society, AAS Meeting #231, id.#211.02
Advertised on:
1
2018
Número de citas
0
Número de citas referidas
0
Descripción
The Apache Point Observatory Galactic Evolution Experiment (APOGEE) is a
near-infrared (1.5-1.7 microns), high resolution (R~22,500), high S/N
(>100), spectroscopic survey as part of the Sloan Digital Sky Survey
(SDSS). Among the goals of this survey is multi-epoch monitoring of
exoplanetary systems discovered by the Kepler mission, resulting in very
high S/N (typically a few hundred) observations of Planet-hosting stars.
The combined visits and sensitivity of the Sloan 2.5-meter telescope
yield stellar parameters for a large number of planet-hosting systems
with higher precision (e.g., $\sigma_{[Fe/H]} < 0.05$ dex), and
deeper observations (H<14) than many other spectroscopic surveys of
similar scale. We have combined this rich dataset with orbital and
planetary properties from the Kepler mission to reveal a correlation
with stellar metallicity and planet orbital period in close-in (P<100
days), small (R_p < 20 R_earth) exoplanetary systems. In particular,
we find that planets with orbital periods P ≤ 8.5 days have
statistically more metal-enriched hosts than planets with P > 8.5
days. This dichotomy implies that there may be different formation
histories between these two populations. For example, there may be a
protoplanetary disk inner-radius (such as the gas co-rotation radius or
the dust-sublimation radius) with a metallicity-dependence at the time
of planet formation that allows small, rocky planets to either form or
migrate closer in to their host star in metal-rich conditions. In
addition, based on previous work about the "Evaporation Valley", there
is theoretical support that this critical period of 8.5 days may be tied
to the bulk composition of the two exoplanet populations.