Radius measurement in binary stars: simulations of intensity interferometry

Abstract

Mass and radius measurements of stars are important inputs for models of stellar structure. Binary stars are of particular interest in this regard, because astrometry and spectroscopy of a binary together provide the masses of both stars as well as the distance to the system, while interferometry can both improve the astrometry and measure the radii of the stars. In this work we simulate parameter recovery from intensity interferometry, especially the challenge of disentangling the radii of two stars from their combined interferometric signal. Two approaches are considered: separation of the visibility contributions of each star with the help of differing brightness ratios at different wavelengths, and direct fitting of the intensity correlation to a multi-parameter model. Full image reconstructions is not attempted. Measurement of angular radii, angular separation and first-order limb-darkening appears readily achievable for bright binary stars with current instrumentation.

arXiv comment12 pages, 11 figures

References in corpus (11)

• emcee: The MCMC Hammer
• Transit spectrophotometry of the exoplanet HD189733b. I. Searching for water but finding haze with HST NICMOS
• Determining stellar parameters of asteroseismic targets: going beyond the use of scaling relations
• Optical Intensity Interferometry with the Cherenkov Telescope Array
• Demonstration of stellar intensity interferometry with the four VERITAS telescopes
• Optical intensity interferometry observations using the MAGIC imaging atmospheric Cherenkov telescopes
• Intensity interferometry of P Cygni in the H$\alpha$ emission line: towards distance calibration of LBV supergiant stars
• Intensity interferometry with more than two detectors?
• Stellar modelling of Spica, a high-mass spectroscopic binary with a beta Cep variable primary component
• Capabilities of future intensity interferometers for observing fast-rotating stars: imaging with two- and three-telescope correlations
• Towards a Polarisation Prediction for LISA via Intensity Interferometry