标题： HARPS对南天外星行星的搜索：XXVI：七个新的行星系统 显示英文标题

标题： The HARPS search for southern extra-solar planets: XXVI: Seven new planetary systems

摘要： 我们自七年前开始使用HARPS进行行星搜索调查。 体积有限的恒星样本包括57.5秒差距内的所有F2至M0主序星，在这些恒星中系统地使用径向速度技术寻找系外行星的迹象。 在本文中，我们报告了七颗主序星和一颗巨星的新亚恒星伴星的发现，这些伴星是通过安装在ESO 3.6米望远镜上的仪器HARPS进行多次多普勒测量检测到的，该望远镜位于智利拉西拉天文台。 这些系外行星围绕恒星HD 1690、HD 25171、HD 33473A、HD 89839、HD 113538、HD 167677和HD 217686运行。 已发表的围绕HD 72659的巨行星也在此进行了分析，通过增加HARPS和Keck数据，其轨道元素得到了更精确的确定。 其他发现的行星是位于遥远轨道上的巨行星，质量范围从0.3到29 MJup，轨道周期在0.7到10年之间。 这些新行星宿主恒星的低金属量加强了目前在贫金属恒星周围发现长距离行星的趋势。 长期的径向速度调查允许探测系外行星系统的外围，尽管在观测覆盖超过一个轨道周期之前，解决方案的置信度可能较低。 对于本文讨论的许多系统，需要更长的时间基线来优化径向速度拟合并推导行星参数。 还分析了恒星BD -114672和HIP 21934的径向速度时间序列，并将其行为解释为恒星活动周期的结果，而不是长周期行星伴星。 显示英文摘要

摘要： We are conducting a planet search survey with HARPS since seven years. The volume-limited stellar sample includes all F2 to M0 main-sequence stars within 57.5 pc, where extrasolar planetary signatures are systematically searched for with the radial-velocity technics. In this paper, we report the discovery of new substellar companions of seven main-sequence stars and one giant star, detected through multiple Doppler measurements with the instrument HARPS installed on the ESO 3.6m telescope, La Silla, Chile. These extrasolar planets orbit the stars HD 1690, HD 25171, HD 33473A, HD 89839, HD 113538, HD 167677 and HD 217686. The already-published giant planet around HD 72659 is also analysed here, and its elements are better determined by the addition of HARPS and Keck data. The other discoveries are giant planets in distant orbits, ranging from 0.3 to 29 MJup, in mass and between 0.7 and 10 years in orbital period. The low metallicity of most of these new planet-hosting stars reinforces the current trend for long-distance planets around metal-poor stars. Long-term radial-velocity surveys allow probing the outskirts of extrasolar planetary systems, although confidence in the solution may be low until more than one orbital period is fully covered by the observations. For many systems discussed in this paper, longer baselines are necessary to refine the radial-velocity fit and derive planetary parameters. The radial-velocity time series of stars BD -114672 and HIP 21934 are also analysed and their behaviour interpreted in terms of the activity cycle of the star, rather than long-period planetary companions.