J. Á. Docobo, P. P. Campo, Jorge A. Gómez, Luca Piccotti, Camila Caballero-Valdes, R. A. Méndez, E. Costa
Abstract We have used new observational data obtained during the 2020, 2021, 2022, 2023, and 2024 speckle runs with the 4.1 m Southern Astrophysical Research (SOAR) telescope located at Cerro Pachón (Chile) to improve the orbits of the following 21 visual binaries with components of spectral types B and A: WDS 03124-4425 (JC 8 AB), WDS 05010-1112 (A 2629), WDS 05474-1032 (MCA 22), WDS 07374-3458 (FIN 324 AB,C), WDS 08277-0425 (A 550), WDS 13123-5955 (SEE 170), WDS 13320-6519 (FIN 369), WDS 14567-6247 (FIN 372), WDS 15351-4110 (HJ 4786 AB), WDS 16094-3103 (I 557), WDS 16589-3737 (SEE 315), WDS 17104-1544 (BU 1118AB), WDS 17400-0038 (BU 631), WDS 17471-3807 (I 1336), WDS 18150-5018 (I 429, two solutions), WDS 19026-2953 (HDO 150 AB), WDS 19172-6640 (GLE 3), WDS 19253-2431 (FIN 327), WDS 21147-0050 (A 883 AB), WDS 21273-3218 (B 1007), and WDS 21579-5500 (FIN 307). Most of the systems are comprised of main sequence or subgiant stars. In the cases that it is feasible, we have calculated the dynamical parallaxes and individual masses of the components. These parallaxes have been compared with those in the literature.