A Map Based Study of ADS 14893

Abstract

ADS 14893 is found to be subluminous for its spectral type and to be overluminous for its major component masses. The distance and masses of the components of the triple star system are derived from data collected with the Multichannel Astrometric Photometer and the 0.76 m Thaw Refractor at the University of Pittsburgh's Allegheny Observatory. The period and time of periastron passage of the orbit of the visual components are estimated from spectroscopic and astrometric data and checked against speckle and visual double stars measurements. The other orbital elements of the visual pair are then estimated from speckle interferometric observations and an ephemeris is given. The visual orbit derived in this fashion is compared with one based upon the astrometric perturbation. The newly derived trigonometric parallax of is +0".0239±0".0008 corresponding to a distance modulus of 3.11±0.073 mag yielding absolute magnitudes that are subluminous for the F7 V and F8 V spectral types of the major components. When this magnitude and the systems measured B - V index are corrected for the system's UV excess, however, the absolute magnitudes of the A and B components are found to lie on the main sequence. The total mass of the ADS 14893 system is determined to be 2.30±0.65 M<SUB>sun</SUB>. The photocentric semimajor axis of the A, B/C orbit is 0".0163±0".0010 indicating masses of 0.81±0.23 for the A component and 1.49±0.42 for the B/C subsystem. West (1976) finds a mass function for the B/C system which suggests that the C component is more massive than B component. Thus the A and B components of this UV-excess system are over luminous for their masses but subluminous for their B - V color index and spectral type.