摘要
使用加拿大自治领天体物理台(DAO)的视向速度仪及光栅摄谱仪,获得了分光双星HD144515和HD178428的新的视向速度。结合文献中前人的观测资料,HD144515的轨道运动周期测定为4.285439±0.000009天;HD178428的为21.95582±0.00032天。HD144515的速度曲线的半变幅K有重要的改进。两双星的轨道偏心率e获得显著的修正。
Twenty-four and thirty new radial velocities were secured for the spectroscopic binaries HD144515 and HD178428, respectively, with the radial-velocity spectrometer mounted at the coude focus of the 1.2-m telescope of the Dominion Astrophysical Observatory. One additional velocity was obtained with the 3282 spectrograph of the same telescope. With these observations and those in the literature, the orbital period of HD144515 is determined to be 4.285439 ± 0.000009 days, whilst that of HD178428 being 21.95582 ± 0.00032 days. In search of the period of HD178428, five early observations were excluded because of their large residuals. The determinations of the other elements of the binaries are based only on the new observations. The semi-amplitude K of HD144515 is much improved with a change from 38.1 km/sec to 47.18 km/sec, which looks unusual. By inspecting Sanford's early work on the binary, it is found that his observations did not cover the minimum of the velocity-curve and poorly covered the maximum, thus leading to a lower K. The eccentricities of the binaries are both revised quite a lot. The value e of HD144515 is derived to be 0.026 instead of 0.089, which makes it one of the spectroscopic binaries whose eccentricities are the smallest but definite like HD149420 and AN And (see [7] ). The eccentricity of HD178428 is 0.124 rather than 0.205.
