Orbital Elements for BU 1240 AB. Nature of the C and D Components

Abstract

New orbital parameters and masses for WDS 05386+3030 = BU 1240 AB were determined prompted by the large residuals seen in recent speckle measurements from 1985. A combined solution of graphical (to determine preliminary parameters) and analytical methods was used. The preliminary orbit was rened using the differential correction method by Heintz. The physical characteristics of the C and D components were studied using BVIJHK photometry, historical astrometry and kinematical data. Several criteria indicate a physical nature for C and an optical nature for D.