Applications of separated fringe packets to binary star studies with the CHARA Array: preliminary thesis report

Abstract

The use of high-resolution techniques for detecting binary and multiple star systems, such as speckle interferometry, and extensive spectroscopic survey efforts have led to the discovery of stellar systems over a broad range of orbital periods. However, there remains a gap between these two techniques, wherein neither is sensitive to detection of companions. Thus, it is possible that some nearby stars may have companions that have been overlooked. Using the longest baselines of the CHARA Array (~275-330 m), we are examining 158 nearby F and G dwarfs previously included in speckle interferometry and radial velocity surveys. Included in this sample are previously unresolved double- and single-lined spectroscopic binaries that show separated fringe packets measured on two nearly perpendicular baselines to determine true position angle and angular separation. Specifically, we are exploring the spectroscopic sample of Duquennoy and Mayor and include selected systems from the CHARA Catalog of Orbital Elements of Spectroscopic Binaries that have predicted separations that fall in this gap. In addition to the search for new companions, we will attempt to use astrometric data to determine orbital inclination in conjunction with previously determined spectroscopic orbits for accurate mass determination. We intend to utilize the Array to more fully explore the undersampled regime of approximately 5-50 mas to characterize the completeness of the multiplicity in the stellar neighborhood.