NOAO >   Observing Info >   Approved Programs >   2015A-0207

# Program Information for 2015A-0207

PI: Mark Everett, NOAO, everett@noao.edu
Address: SCI, 950 N. Cherry Ave., Tucson, Arizona 85719 U.S.A.

CoI: Steve B Howell, NASA Ames Research Center
CoI: David R Silva, NOAO
CoI: Paula Szkody, U. of Washington

Title: Spectroscopy of Kepler Candidate Exoplanet Host Stars

Abstract: Currently the NASA {\it Kepler} Mission has identified 4233 exoplanet candidate and confirmed planets, over 20\% having estimated radii ${\rm R_p<2.5R_\oplus}$ and orbiting faint (${\rm m_{Kep}>15}$) host stars. The NASA sponsored {\it Kepler} Follow-up Observing Program is focusing on small exoplanet candidates (${\rm R_p<2.5R_\oplus}$) and those in habitable zone orbits. Planet radii estimates depend on estimates of host star radii. Based on spectra previously obtained at the KPNO Mayall 4-m for 220 stars with candidate exoplanets, Everett et al.~(2013) have shown that many host stars are larger than originally assumed (up to factor of 2). Therefore, the exoplanet candidates they host must be larger than originally assumed, which conversely reduces the number of known Earth-sized exoplanet candidates. Determination of the frequency of such Earth-sized planets is a cornerstone {\it Kepler} mission objective and of keen general interest. These Mayall spectra were also used to confirm the Buchhave et al.~(2012) result that exoplanet candidates larger than ${\rm 4R_\oplus}$ in short-period orbits are preferentially associated with host stars with solar or higher metallicity. In short, followup Mayall optical spectroscopy is {\bf critical} to confirming the detection of Earth-sized exoplanets, a {\it Kepler} cornerstone goal, as well as characterizing the relationship between host star properties and planetary system properties. Here, we propose observations with a focus on the smallest (most rare) exoplanet candidates orbiting the faintest {\it Kepler} host stars.

Program Type: Standard/Solar System

Scheduled Nights:
Run 1 (2015A):  KP-4m/RCSP -- 7n on Jun 17 - Jun 23 2015

National Optical Astronomy Observatory, 950 North Cherry Avenue, P.O. Box 26732, Tucson, Arizona 85726, Phone: (520) 318-8000, Fax: (520) 318-8360

 NOAO >   Observing Info >   Approved Programs >   2015A-0207