arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0908.1753astro-ph.EP
收藏

K巨星11 UMi和HD 32518周围的行星伴星

Planetary companions around the K giant stars 11 UMi and HD 32518

M. P. Döllinger, A. P. Hatzes, L. Pasquini, E. W. Guenther, M. Hartmann

摘要:

[11] UMi和HD 32518属于62 K巨星的样本,自2004年2月以来一直使用图林根Landessternwarte(TLS)的2米阿尔弗雷德·詹士望远镜进行观测,以精确测量径向速度(RV)。这次巡天的目的是通过寻找中等质量巨星周围的行星伴星来研究行星形成对主恒星质量的依赖性。使用碘吸收池获得本研究的准确RV。我们的测量结果表明,11 UMi的RV显示出516.22天的周期变化。HD 32518的RV曲线显示正弦变化,周期为157.54天。依巴谷测光以及我们的Hα核通量测量结果表明,RV周期没有变化。因此,开普勒运动是最有可能解释这两颗巨星观测到的RV变化。一颗最小质量为10.5木星质量的系外行星围绕K巨星11 UMi运行。K1 III巨星HD 32518拥有一颗质量至少为3.0木星质量的行星伴星,其轨道接近圆形。这是TLS调查中公布的第4和第5颗行星。

英文摘要:

11 UMi and HD 32518 belong to a sample of 62 K giant stars that has been observed since February 2004 using the 2m Alfred Jensch telescope of the Thüringer Landessternwarte (TLS) to measure precise radial velocities (RVs). The aim of this survey is to investigate the dependence of planet formation on the mass of the host star by searching for planetary companions around intermediate-mass giants. An iodine absorption cell was used to obtain accurate RVs for this study. Our measurements reveal that the RVs of 11 UMi show a periodic variation of 516.22 days. The RV curve of HD 32518 shows sinusoidal variations with a period of 157.54 days. The HIPPARCOS photometry as well as our Hαcore flux measurements reveal no variability with the RV period. Thus, Keplerian motion is the most likely explanation for the observed RV variations for both giant stars. An exoplanet with a minimum mass of 10.5 Jupiter masses orbits the K giant 11 UMi. The K1 III giant HD 32518 hosts a planetary companion with a minimum mass of 3.0 Jupiter masses in a nearly circular orbit. These are the 4th and 5th planets published from this TLS survey.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑