Abstract Title: *
NEW LINEAR SOLUTIONS FOR 13 DOUBLE STARS

Authors: *
Zorica Cvetković and Rade Pavlović

Institution: *
Astronomical Observatory

Preferred format: *
Oral

Abstract Text: *
We present 13 linear solutions of double stars that have been calculated 
for the first time during 2016 and 2017. For the purpose of calculating 
the linear solutions, we also use our measurements of the position angle 
and angular separation obtained from CCD frames performed at NAOR and 
ASV. Two linear elements, V_x and V_y , are used to calculate the 
velocity V of relative motion of the secondary with respect to the 
primary. Also, we can calculate the relative proper motion μ_rel for 
these 13 double stars by using the components of the proper motion, 
μ_α cosδ and μ_δ, for primary A and secondary B. The components of the 
proper motion are taken from two sources, WDS catalog 
(http://www.usno.navy.mil/USNO/astrometry/optical-IR-prod/wds) and URAT1
(http://vizier.u-strasbg.fr/viz-bin/VizieR?-source=I/329). Then, we can 
compare the proper motion μ_rel with the values of the relative velocity 
V for all 13 components in linear solutions. Excellent agreement between 
them was found when we used the proper motions from the URAT1 catalog to 
calculate μ_rel.