Light-time orbit and apsidal motion of the eclipsing binary U Ophiuchi |
| |
Authors: | B -C Kämper |
| |
Institution: | (1) Berliner Arbeitsgemeinschaft für Veränderliche Sterne e.V. (BAV), Berlin, F.R.G. |
| |
Abstract: | A comprehensive period study of the times of minima observed from 1881 to 1985 has been performed. Previous interpretations of the O–C diagram based on light-time effect are confirmed. The light-time orbit of U Oph has been revised using a differential corrections procedure. We get an eccentric orbit withe =0.22±0.06,P =38.7±0.2 yr, and a mass function
. In addition, our analysis has revealed short-period apsidal motion (U/P=4515±75) in a slightly eccentric close orbit (e=0.0031±0.0003), allowing a reliable determination of the density concentration coefficient,k
2=0.0059±4. A comparison with stellar evolutionary models calculated by Jeffery (1984) yields the helium contentY=0.28±0.05 and an age of 3×107 yr for the components of U Oph. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|