A survey of the types of stars and massive planets that make up binary pairs in the Milky Way Galaxy

University Of Virginia Main Campus, Charlottesville VA

Investigators

Abstract

Scientists from the University of Virginia and Northern Kentucky University will work together to count how many stars in the Milky Way galaxy exist in pairs. Using an instrument that splits the light from each star into a "spectrum" they will show if each pair is made up of large or small stars, hot or cold stars, old or young stars. With this information astronomers can better understand how stars form in the Milky Way, and how important being a member of a pair can be to the birth of planets. The light from over 163,000 stars will be analyzed over a three year period by graduate and undergraduate students from each university. The data will be obtained using the Sloan Foundation Telescope at the Apache Point Observatory in New Mexico and the Irénée du Pont Telescope at Las Campanas Observatory in Chile. This is a collaborative proposal between Steven Majewski of the University of Virginia (UVa) and Nathan De Lee of Northern Kentucky University (NKU). Together with graduate and undergraduate students at both universities, these researchers propose to analyze Apache Point Observatory Galactic Evolution Experiment (APOGEE) radial velocity survey data of 163,000 stars spread throughout the galaxy (disk, halo and bulge) to search for companions to stars with a broad range of stellar spectral types, metallicities, and ages. They will exploit data acquired as part of the SDSS-III/APOGEE-1 high-resolution IR spectroscopic survey, which has already observed over 14,000 stars in multiple (dozens of) epochs. The proposers will complement these data with a new survey, SDSS-IV/APOGEE-2, to extend temporal baselines and the number of observed sources. Their goal is to determine the frequency of companions as a function of host star chemistry, dynamics, evolutionary stage, position in the Milky Way, and environment. They also propose follow-up near-IR speckle interferometric observations of a sample of targets using a new speckle camera on the WIYN telescope, which they plan to build with funds from this award. A pilot spectroscopic survey based on APOGEE-1 data has already produced samples of stellar, brown dwarf, and hot Jupiter companions in a few hundred systems. Dr. Majewski is the PI of both the APOGEE-1 and APOGEE-2 projects.