We present 119 position angle and separation measures of 86 double stars observed by way of speckle interferometry with the University of Toronto Southern Observatory 60 cm telescope at Las Campanas, Chile. Speckle interferograms are recorded with a bare (unintensified) front-illuminated CCD in a fast subarray-readout mode. Position angles and separations are determined by a weighted least-squares fitting algorithm applied to the binary power spectra, and the 180-degree ambiguity in the position angle inherent in this approach is resolved by bispectral analysis. In this configuration the 60 cm telescope exhibits near-diffraction-limited performance. Initial results indicate that our separation measures have a root-mean-square (rms) deviation of 6.6 +/- 1.0 milliarcsecond (mas) and our position angles have an rms deviation of 1.73 +/- 0.26 degrees when judged against the ephemeris positions of a small sample of binaries with previously well-determined orbits (Refer to PDF file for exact formulas).
Department, Program, or Center
Chester F. Carlson Center for Imaging Science (COS)
Astronomical Journal 114N5 (1997) 2117-2127
RIT – Main Campus