Speckle interferometry of southern double stars .1. First results of the Yale San Juan speckle interferometry program

We present position angle and separation measures for 60 double stars from speckle observations at El Leoncito, Argentina between 1994 July and 1995 February, The data were taken with a multianode microchannel array (MAMA) detector system, which we have on long term loan from J. G. Timothy of the University of New Brunswick, Canada. Most of the observations were performed on the 76-cm telescope at the Cesco Observatory, but others were taken using the 2.15-m telescope at Complejo Astronomico El Leoncito. The method of deducing position angle and separation measures from the raw data is a weighted least-squares fit to the object spatial frequency power spectrum. The position angle ambiguity inherent in power spectrum analysis is resolved in most cases by computing the directed vector autocorrelation of Bagnuolo et al. [Proc. SPIE, 1237, 286 (1990); AJ, 103, 1399 (1992)], and in the remaining cases by performing a full speckle imaging analysis. (C) 1996 American Astronomical Society.