Applications of Infrared Imaging Interferometry: Binaries, Rapid Rotators, and Hot Jupiters.

Infrared Interferometry;Rapid Rotators;Binary Stars;Hot Jupiters;Optical Aperture Synthesis Imaging;Astronomy;Science;Astronomy and Astrophysics

Zhao, MingMateo, Mario L. ;

University of Michigan

关键词: Infrared Interferometry;    Rapid Rotators;    Binary Stars;    Hot Jupiters;    Optical Aperture Synthesis Imaging;    Astronomy;    Science;    Astronomy and Astrophysics;   

Others  :  https://deepblue.lib.umich.edu/bitstream/handle/2027.42/64644/mingzhao_1.pdf?sequence=1&isAllowed=y

瑞士|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Long baseline optical inerferometers now have the power to resolve objects as small as 0.5 milliarcseconds in the near-IR and possess the capability of conducting real aperture synthesis imaging, allowing us to study stars and their environments in unprecedented detail. As a fundamental property of stars, rotation affects stars’ luminosities, effective temperatures, and their evolution. Since most of hot stars arerapid rotators, understanding the effects of rotation will shed light on critical areas of stellar evolution and basic astrophysics. Using the CHARA array and the MIRC combiner, we resolved the surfaces of three rapid rotators, α Cep, α Oph and Altair. We reconstructed an image for α Cep, and modeled the surface brightness distribution for all three stars, allowing us to confirm the ;;gravity darkening” phenomenon andinvestigate the impact of rapid rotation on their locations in the H-R diagram. Our modeling of rapid rotators also allowed us to propose a new way of measuring masses of stars. We also studied binary stars with IR interferometers. We conducted combined interferometric and spectroscopic study of the metallic-lined A star λ Vir, permitting us to determine its orbital and physical properties to high accuracy. The determination of masses of the system also allowed us to compare observations with stellar evolution models, in which reasonable matches were found. In addition, using CHARA-MIRC we also made the first resolved images of the well-known interacting and eclipsingbinary system β Lyrae, which also allowed us to obtain its full orbital parameters and estimate the masses of its components.Lastly, we present our efforts toward direct detection of nearby hot Jupiters usingprecision closure phases obtained with long baseline interferometer. We present closurephase simulations, preliminary observations on the hot Jupiter system Ups And,as well as calibration studies and test observations of a high contrast binary Eps Per.We conclude that with all the ongoing improvements, it is feasible to achieve the goalof detecting hot Jupiters with CHARA-MIRC.