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Visual Orbits of Spectroscopic Binaries with the CHARA Array Georgia State University ScholarWorks @ Georgia State University Physics and Astronomy Dissertations Department of Physics and Astronomy 5-4-2020 Visual Orbits of Spectroscopic Binaries with the CHARA Array Kathryn V. Lester Follow this and additional works at: https://scholarworks.gsu.edu/phy_astr_diss Recommended Citation Lester, Kathryn V., "Visual Orbits of Spectroscopic Binaries with the CHARA Array." Dissertation, Georgia State University, 2020. https://scholarworks.gsu.edu/phy_astr_diss/121 This Dissertation is brought to you for free and open access by the Department of Physics and Astronomy at ScholarWorks @ Georgia State University. It has been accepted for inclusion in Physics and Astronomy Dissertations by an authorized administrator of ScholarWorks @ Georgia State University. For more information, please contact [email protected]. Visual Orbits of Spectroscopic Binaries with the CHARA Array by Kathryn V. Lester Under the Direction of Douglas Gies, PhD ABSTRACT We present the three dimensional orbits of eight double-lined spectroscopic binaries with longer orbital periods (7–35 days) to determine the fundamental stellar parameters of each component and make critical tests of stellar evolution models. We resolve the position of the secondary stars relative to the primaries on milliarcsecond scales using fringe visibility variations in interferometric observations with the CHARA Array, and measure new radial velocities using echelle spectra from the APO 3.5m, CTIO 1.5m, and Fairborn 2.0m tele- scopes. By combining the visual and spectroscopic observations, we solve for the orbital parameters for these systems and derive the stellar masses and distance. We then estimate the stellar radii from the distance and the angular diameter, set by fitting spectrophotometry from the literature to binary SED models or by directly fitting the interferometric visibilities. Finally, we compare the observed stellar parameters to the predictions of Yonsei-Yale and MESA stellar evolution models in order to estimate the ages of each system. We find that our distances from orbital parallax agree with the Gaia DR2 distances from trigonometric parallax, and that the mass-luminosity relationship for our long period systems generally agrees with that of short period systems. Therefore, the short period eclipsing binaries are good tools for testing models of stellar structure and evolution designed for single stars. INDEX WORDS: Spectroscopic binaries, Visual binaries, Fundamental parameters Visual Orbits of Spectroscopic Binaries with the CHARA Array by Kathryn V. Lester A Dissertation Submitted in Partial Fulfillment of the Requirements of Doctor of Philosophy in the College of Arts and Sciences Georgia State University 2020 Copyright by Kathryn V. Lester 2020 Visual Orbits of Spectroscopic Binaries with the CHARA Array by Kathryn V. Lester Committee Chair: Douglas Gies Committee: Fabien Baron Jane Pratt Gail Schaefer Russel White Electronic Version Approved: Office of Graduate Studies College of Arts and Sciences Georgia State University May 2020 Dedication I would like to dedicate this thesis to my family for their love and support. iv Acknowledgements First and foremost, I would like to thank my wonderful advisor, Dr. Doug Gies, for his knowledge, time, effort, and guidance over the past six years. I would also like to thank my committee members – Dr. Fabien Baron, Dr. Russel White, Dr. Jane Pratt, and especially Dr. Gail Schaefer – for their advice and expertise. Thank you to all of my collaborators – Dr. Chris Farrington, Dr. Frank Fekel, Dr. John Monnier, and Dr. Matthew Muterspaugh – for their contributions to this project, and to all of the staff at APO, CHARA, and CTIO for their hard work and assistance during my observing runs. Thank you to all of the faculty, staff, and grad students in the department, especially: Doug’s research group – Dr. Rachel Matson, Dr. Zhao Guo, Dr. Katie Gordon, Dr. − Luqian Wang, and Katherine Shepard The incoming class of 2014 – Dr. Caroline Roberts, Karen Garcia, Dr. Mitch Revalski, − Dr. Wes Peters, Dr. Sushant Mahajan, and Daniel Horenstein The CHIRON team – Dr. Todd Henry, Dr. Wei-Chun Jao, Leonardo Paredes, and − Hodari-Sadiki James. My roommates and cubicle mates – Dr. Dicy Saylor, Bokyoung Kim, Rachael Merritt − and Justin Robinson. Finally, thank you to all of my friends and family for their support and encouragement. v Institutional support has been provided from the GSU College of Arts and Sciences and the GSU Office of the Vice President for Research and Economic Development. We also acknowledge support from the NASA Georgia Space Grant Consortium. This work is based in part upon observations obtained with: the Apache Point Observatory 3.5 m telescope, owned and operated by the Astrophys- − ical Research Consortium the Cerro Tololo Inter-American Observatory 1.5 m telescope, operated by the Small − and Moderate Aperture Research Telescope System (SMARTS) Consortium the Georgia State University Center for High Angular Resolution Astronomy Array − at Mount Wilson Observatory, supported by the National Science Foundation under Grants No. AST-1636624 and AST-1715788 the Automatic Spectroscopic Telescope at Fairborn Observatory, operated by Ten- − nessee State University (TSU) and supported by the state of Tennessee through its Centers of Excellence Program the Palomar Testbed Interferometer, operated by the NASA Exoplanet Science In- − stitute and the PTI collaboration and developed by the Jet Propulsion Laboratory, California Institute of Technology with funding provided from the National Aeronau- tics and Space Administration the High-Resolution Imaging instrument ‘Alopeke at Gemini-North (GN-2018B-FT- − 102), funded by the NASA Exoplanet Exploration Program and built at the NASA Ames Research Center by Steve B. Howell, Nic Scott, Elliott P. Horch, and Emmett Quigley. This work has also made use of the PyRAF product of the Space Telescope Science Insti- tute, the Jean-Marie Mariotti Center SearchCal service, the CDS Astronomical Databases SIMBAD and VIZIER, the Wide-field Infrared Survey Explorer, and the Two Micron All Sky Survey. vi Table of Contents List of Tables....................................... ....................... x List of Figures...................................... ....................... xii List of Abbreviations ................................ ..................... xv 1 Introduction 1 1.1 BinaryStars.................................... 1 1.2 FundamentalStellarParameters . .. 5 1.3 SampleSelection ................................. 8 1.4 ProjectGoals ................................... 13 2 Spectroscopy 14 2.1 Observations.................................... 14 2.1.1 ARCES .................................. 14 2.1.2 CHIRON ................................. 15 2.1.3 Fairborn .................................. 16 2.2 RadialVelocities ................................. 17 2.3 Preliminary Spectroscopic Orbits . 20 3 Interferometry 28 3.1 BasicsofInterferometry . .. .. 28 3.2 Observations.................................... 32 3.2.1 Speckle Imaging .............................. 32 3.2.2 The CHARA Array ............................ 35 3.2.3 Palomar Testbed Interferometer ..................... 39 3.3 BinaryPositions ................................. 40 vii 4 Analysis 49 4.1 OrbitFitting ................................... 49 4.2 DopplerTomography .............................. 65 4.3 SEDFitting ................................... 75 5 Results 83 5.1 FundamentalStellarParameters . 83 5.2 Comparison to Gaia distances.......................... 86 5.3 Comparison to Evolutionary Models . 87 5.4 ResultsforIndividualSystems. 92 5.4.1 HD 8374 .................................. 92 5.4.2 HD 24546 ................................. 94 5.4.3 HD 61859 ................................. 96 5.4.4 HD 89822 ................................. 97 5.4.5 HD 109510 ................................ 100 5.4.6 HD 185912 ................................ 101 5.4.7 HD 191692 ................................ 103 5.4.8 HD 224355 ................................ 104 5.5 Comparison to Close Binaries . 105 6 Conclusions 108 6.1 Summary ..................................... 108 6.2 FutureWork ................................... 109 References 111 A Light Curve Analysis of HD 185912 122 A.1 Observations.................................... 122 A.2 LightCurveModeling .............................. 122 viii A.3 Results....................................... 125 B Spectroscopic Data Reduction & Analysis Codes 127 B.1 ARCESdatareductionscript . .. .. 127 B.2 Reading & stacking reduced ARCES data . 133 B.3 Measuring RVs with multi-order TODCOR . 141 B.4 Fitting spectroscopic orbits with rvfit ..................... 151 ix List of Tables 1.1 Sample of Spectoscopic Binaries . 10 2.1 RadialVelocityMeasurements ......................... 21 2.1 RadialVelocityMeasurements ......................... 22 2.1 RadialVelocityMeasurements ......................... 23 2.1 RadialVelocityMeasurements ......................... 24 2.1 RadialVelocityMeasurements ......................... 25 2.1 RadialVelocityMeasurements ......................... 26 2.1 RadialVelocityMeasurements ......................... 27 3.1 LongBaselineInterferometers . .. 29 3.2 Minimum Periastron Distance of a Stable Tertiary Companion . ... 33 3.3 CHARAObservingLog ............................. 37 3.3 CHARAObservingLog ............................. 38 3.4 PTIObservingLogforHD8374 ........................ 39 3.5 AngularDiametersfromSearchCal . 40 3.6 PredictedComponentAngularDiameters
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