Keith Knox (Air Force Research Laboratory)
Keywords: double stars, binary stars, binaries, speckle interferometry
Abstract:
Speckle interferometry (Labeyrie, 1970) is a well-tested and still used method for detecting and measuring binary stars that are closer together than the width of the atmospheric seeing disk. In this method, an average spatial power spectrum is computed from a series of short-exposure images. The power spectrum exhibits clearly defined cosine fringes, while the autocorrelation function (its Fourier Transform) contains a central peak with two side lobes. Over the years, several methods have been developed to analyze either the autocorrelation function or the power spectrum to determine the separation and orientation of the binary star system (Horch, 1996, Tokovinin, 2010). In this talk, a method for analyzing the fringes in the power spectrum will be described that can robustly detect and measure the fringes. The method is based on the detection of the fringe minima. It will be shown that the location of the fringe minima is insensitive to the absolute calibration of the power spectrum. As a result, this method provides a more robust estimation of the separation and orientation of the binary star system than is available with current methods.
Date of Conference: September 9-12, 2014
Track: Sensor Processing