A High-Eccentricity Low-Mass Companion to HD 89744
A High-Eccentricity Low-Mass Companion to HD 89744
复制标题
HD 89744 的高偏心率低质量伴侣
DOI：
10.1086/312611
复制
发表时间：
2000
期刊：
影响因子：
--
通讯作者：
R. Noyes
中科院分区：
文献类型：
--
作者：
S. Korzennik;T. Brown;D. Fischer;P. Nisenson;R. Noyes
HD 89744是一颗F7 V恒星，质量为1.4 M☉，有效温度为6166 K，年龄为2.0 Gyr，金属丰度[Fe/H] = 0.18。自 1996 年以来，惠普尔天文台的高级光纤阶梯光栅摄谱仪一直在监测这颗恒星的径向速度，并发现了低质量伴星的证据。这些数据得到了利克天文台汉密尔顿摄谱仪在 1999 年秋季伴星经过近星体过程中的补充数据的补充。因此，我们确定了该恒星的轨道摆动周期 P = 256 天，轨道振幅 K = 257 m s-1，偏心率 e = 0.7。根据恒星质量，我们推断伴星在半长轴 a2 = 0.88 AU 的轨道上的最小质量为 m2 sin i = 7.2 MJ。其轨道偏心率是已知的太阳系外行星中最高的，延续了半长轴大于约 0.15 天文单位的太阳系外行星的偏心率往往比太阳系中的偏心率高得多的趋势。母恒星的高金属丰度强化了太阳系外行星的母恒星往往具有高金属丰度的趋势。
HD 89744 is an F7 V star with a mass of 1.4 M☉, an effective temperature of 6166 K, an age of 2.0 Gyr, and metallicity [Fe/H] = 0.18. The radial velocity of the star has been monitored with the Advanced Fiber-Optic Echelle spectrograph at the Whipple Observatory since 1996, and evidence has been found for a low-mass companion. The data were complemented by additional data from the Hamilton spectrograph at Lick Observatory during the companion's periastron passage in the fall of 1999. As a result, we have determined the star's orbital wobble to have a period P = 256 days, an orbital amplitude K = 257 m s-1, and an eccentricity e = 0.7. From the stellar mass, we infer that the companion has a minimum mass m2 sin i = 7.2 MJ in an orbit with a semimajor axis a2 = 0.88 AU. The eccentricity of the orbit, among the highest known for extrasolar planets, continues the trend that extrasolar planets with semimajor axes greater than about 0.15 AU tend to have much higher eccentricities than are found in our solar system. The high metallicity of the parent star reinforces the trend that parent stars of extrasolar planets tend to have high metallicity.
影响因子：
3.2
作者：
V. Mannings;A. Boss;S. Russell
通讯作者：
V. Mannings;A. Boss;S. Russell