info:eu-repo/semantics/article
A three-dimensional orbit for the binary star Alpha Andromedae
Fecha
2017-01Registro en:
Branham, Richard Lacy; A three-dimensional orbit for the binary star Alpha Andromedae; Wiley Blackwell Publishing, Inc; Monthly Notices of the Royal Astronomical Society; 464; 1; 1-2017; 1095-1101
0035-8711
CONICET Digital
CONICET
Autor
Branham, Richard Lacy
Resumen
Stars that are both spectroscopic and optical binaries present a means to determine simultaneously the masses of the components and the distance of the system independent of trigonometric parallax. Alpha Andromedae (Alpheratz) represents such a system and, moreover, the primary is the brightest of the mercury-manganese stars. An orbit, based on 42 interferometric observations and 378 radial velocities, is calculated to solve for 10 parameters: the six coefficients of the apparent ellipse, the constant of areal velocity, the systemic velocity, and the semiamplitudes. From these, one calculates the orbit of the binary, its period and time of periastron passage, the masses of the components, and the distance of the system. The dynamical parallax does not differ greatly from the trigonometric parallax found from Hipparcos.