An Astrometric Study of the Low-Mass Binary Star Ross 614
An Astrometric Study of the Low-Mass Binary Star Ross 614
复制标题
低质量双星 Ross 614 的天体测量研究
DOI：
--
复制
发表时间：
2003
期刊：
影响因子：
--
通讯作者：
I. Han
中科院分区：
文献类型：
--
作者：
G. Gatewood;L. Coban;I. Han
长期以来，附近小型天体测量双星罗斯 614 的副星一直被认为是典型的低质量恒星，引起了天体物理学界的极大兴趣。不幸的是，16.6 年的轨道周期超过了大多数星载或仪器验证观测计划的任务限制研究的持续时间。与大多数此类双星一样，唯一的全轨道研究都是基于摄影材料。该系统的最后一次扩展研究是基于麦考密克和斯普劳尔天文台的板块收藏。这里报告的工作结合了来自多通道天体测量光度计、依帕谷中间天体测量数据、阿勒格尼天文台以前未测量的照相底片、已发表的视觉双星观测结果以及最近发表的系统径向速度的数据。这些数据总共跨越了低质量双星系统的三个以上轨道。将我们的分析限制在对双星系统的最新观测结果以及与它们相当一致的五个旧观测结果中，我们发现主星和副星的质量分别为 0.2228 ± 0.0055 和 0.1107 ± 0.0028 M⊙，最大的误差源是系统的视觉分离。我们发现视差为 244.07 ± 0.73 mas，周期为 16.595 ± 0.0077 年，半长轴的估计值增加为 1101.2 ± 8.2 mas。后者导致计算质量显着增加。轨道元素和天体测量的所有其他方面与麦考密克和斯普劳尔板块的独立研究中发现的结果非常一致。系统的轨道运动仅在依巴谷星表编制过程中产生加速，这一事实指出了长期天体测量覆盖的重要性。从这些高精度但短期的数据中无法辨别出轨道参数或质量估计。
Long accepted as the quintessential low-mass star, the secondary of the nearby diminutive astrometric binary Ross 614 has attracted considerable astrophysical interest. Unfortunately, the orbital period of 16.6 yr exceeds the duration of the mission-limited studies of most space-borne or instrumental-proving observational programs. As with most such binaries, the only full-orbit studies are based on photographic materials. The last extended study of this system was based upon the plate collections of the McCormick and Sproul Observatories. The work reported here combines data from the Multichannel Astrometric Photometer, the Hipparcos Intermediate Astrometric Data, the previously unmeasured photographic plates of the Allegheny Observatory, published observations of the visual binary, and recently published radial velocities of the system. Together, these data span more than three orbits of the low-mass binary system. Limiting our analysis to the most recent observations of the binary, and five older observations that are in fair agreement with them, we find masses of 0.2228 ± 0.0055 and 0.1107 ± 0.0028 M⊙ for the primary and secondary, respectively, with the largest source of error being the visual separations of the system. We find a parallax of 244.07 ± 0.73 mas, a period of 16.595 ± 0.0077 yr, and an increased estimate of the semimajor axis of 1101.2 ± 8.2 mas. The latter led to a significant increase in the computed masses. All other aspects of the orbital elements and astrometry are in excellent agreement with those found in the independent study of the McCormick and Sproul plates. The importance of long-term astrometric coverage is pointed out by the fact that the orbital motion of the system only resulted in an acceleration during the compilation of the Hipparcos Catalogue. No orbital parameters or mass estimates can be discerned from these high-precision but short-term data.